# Craftsman bushing replacement



## jengele (Nov 1, 2011)

I have a craftsman 8/26 model 536.909800

The drive belt keeps slipping off and the shaft for the large pulley is wobbly.
This blower has a belt for the drive assembly that is tightened by the idler and handlebar lever just like the auger (from my searching the internet this seems to be a little unusual). The speed disk does not raise up to contact the friction disk (like most snowblowers), the friction disk lowers to contact the speed disk. The rubber friction disk assembly has a sprocket on one end with a chain drive to a shaft in back, this shaft then turns a sprocket on the other end with a chain that drives the wheel axle. These two shafts (the one in back and the wheel axle) are contained in the aluminum housing parallel to each other. Perpendicular to them in the middle of this housing is the short shaft I'm having trouble with.

I need help getting my aluminum "support and Bearing assembly" apart so I can change the bushings in it. The shaft that has the speed disk on one end and the drive pulley on the other is wobbly and the bushings are worn out. I'm not sure what needs to come off for example: do I take the friction disk assembly off the top? Do I need to take the wheels and axle off? Does everything need to come out? I'm hoping I can just take the friction disk assembly out and that will provide access to slide the short vertical shaft out and replace the bushings without removing the aluminum "support and bearing assembly". Does this sound right? How do I remove the hex shaft with the friction disk on it? It has a sprocket on the left as shown in the 2nd and 3rd photos. I'm not sure how to remove this. Do I have to remove the chain first? It's difficult to reach the bolt (that is in back) with a wrench on that bearing because it is recessed inside the angle iron that the shaft goes through.

I have the manual and parts diagrams and lists so that helps a little, but I still need guidance. I've watched a few of donyboy73's videos on youtube but I can't find any that help me with this particular scenario.

Also, because the friction disk assembly raises and lowers to contact the speed disk, there is sometimes slack in the chain on the left side, (photo attached). There seems to be a spring loaded tensioner but it doesn't appear to be tensioning anything when the disk is in the lowered "drive" position and the slack in the chain looks troublesome to me. How do I adjust this?

Thanks for any help you can provide,

Jim
Massachusetts 
just recovering from 15" of wet snow, downed trees and power out.


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## HCBPH (Mar 8, 2011)

*Bushings*

Jim

Take a look at this thread, you'll find some of what you need I believe
http://www.snowblowerforum.com/foru...nce-forum/584-alternate-substitute-parts.html
Your pulley/disc wobble is likely due to worn bushings in there








You may also have wear on the shaft, which will either need repair or replacement. To get this assembly out, you'll need to pull the axel along with the upper mount to remove it. There are 6 bushings in that assembly so if this is a keeper machine, I'd change all 6 right away if there's any indication of wear and grease them good during reassembly. There's a void in between the bushings, could put some extra grease in there too.
The bushings on the friction disc assembly are available so if those are worn, replace those too.
You should have an idler on the chain on the left to take up slack, so it may be the bushing issue or a stretched chain so replace that right away if that's the case. On this one, the idler worked best on the outside of the drive chain, pushing it inward to take out the slack.
This one was missing the tensioning mechanism on the disc so I made my own. Originally it had a pivot along with a tensioning spring in the handlebar area. It had gone missing before I bought it, so this is what I came up with after fixing the other issues.








That should get you started with your repairs. I doubt it's everything but until you fix some of them, shot of replacing everything, you need to eliminate some of them before you can identify or repair the rest.

One other thing, get yourself some good penetrant along with some scotchbrite pads, you'll need it to clean up that drive axel to get it out. You will also need some wrenches and sockets, hammer and some punches to remove various rollpins, some white grease and other things as you come up against them.


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## jengele (Nov 1, 2011)

*disassembly*

Okay, all very helpful. Thank you for your quick response.

Focusing on removal for now, I started trying to remove the bearings for the hex axle the rubber friction disk is on. Instead of doing that, I should remove the bracket assembly they are attached to as a whole first (like in the first picture you posted), is that what you are saying? After that I need to basically pull everything out. 

I was aware from the manual that there are two bushings for the shaft in question and two each for the other two shafts (six total).

Quote: "On a Craftsman 536.90515 snowblower, there are 2 bronze bushing on the shaft that fits between the pulley and friction plate. If you can’t find one like that, a B&S 50304MA for a auger gearbox was almost exactly the same dimensions (very slight difference in length, otherwise the same) and pressed in a worked perfectly."

It sounds like these might work on mine as well. Besides that, are you saying I need to pull the bearings out to get the dimensions and take that info with me to search out replacements either in store or online? 

Quote: "The bushings on the friction disc assembly are available so if those are worn, replace those too"

I searched searspartsdirect.com with the parts numbers from the manual and the only bearings that are available from them are the axle bearings #48666. All other bearings in question (six on the support and bearing assembly and two on the hex shaft) are not available.

btw, the manual actually says, "The replacement of the disk drive on this unit is a major service operation and should be done by a trained technician. The entire disk drive and carriage assembly must be removed."

I'm in over my head I know it, but isn't that what this forum is all about? Thanks again for your help.


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## jengele (Nov 1, 2011)

OK, I've made great progress this morning thanks to your help HCBPH. I had a mental stumbling block over the friction disk assembly but now that I realized I just had to remove the 3/4" bolts on the ends of that shaft and disconnect the gear lever, the whole thing came right out no problem.
I also discovered that the chain idler on the left gear (that is not taking out the slack in the chain when the friction disk is lowered), is not working because the spring connected to its arm is too long in the resting position and it keeps the sprocket towards the chain in back but not enough to reach it. I think if I used a compression spring that actually pushes the sprocket to the back that could work or I could use a much shorter spring that pulls the sprocket into the chain in front.
I have the wheels off, I've started taking the bearing covers off of the axle and the shaft in back. I'm concerned how this whole assembly is going to come out. I've removed the gear cover on the right. Everything looks loose but I am wondering if I have to remove the axle first? That's my main question now, do I have to free up the big gear(on the right) on the axle and the locking collar on the left side and slide the axle out before I can remove the rest of the assembly?

According to the manual, the gear has a set screw and a Pin, Drive-Lok, 5/16x 1 1/2".

The locking collar on the left has a Roll Pin, 1/4" x 1 1/4" (indicated as a standard hardware item).

I assume the roll pin can be driven out with a punch but what about the drive-lok pin? Same way?


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## jengele (Nov 1, 2011)

*diassembly*

Okay,

I jumped in and got the whole assembly taken apart. I had to remove the left panel from the snowblower to get the assembly out. then with a little effort, I got all 3 shafts removed from the assembly. The axle is bent and I'll have to straighten it somehow. Any suggestions? Regarding the aluminum housing and the six bearings that are in it: How do I remove them? The bearings that supported the vertical shaft (drive pulley on one end and the speed disk on the other) appear to be the roller bearing type. It had failed and the roller bearings were falling out. I don't know how to remove these, can I just drive them out? Can I hold the assembly in a vise and using a screwdriver, hammer out the bearings? Also, the photo shows that there is a little crack in the housing surrounding the bearing. It looks like if I put a new bearing in it it shouldn't be a problem, but I have no experience, what do you guys think?  

What kind of grease do you recommend? low temp grease, axle grease, white lithium grease, my hardware store doesn't have a good selection, I'll have to go to our local autozone or something.


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## jengele (Nov 1, 2011)

Also, I need 4 bushings for the axle and rear shaft (part #48666 Bearing, self aligning , according to the manual)

4 bushings for the aluminum support and bearing assembly (part #35499 Bearing)

and 2 bearings for the vertical speed shaft (part #41701 Bearing) (these are the roller bearing type)

All shafts appear to be 3/4" although I haven't measured yet. Any advice on bearings? I will search mfgsupply.com and see what I can find but I don't know my bearings so I'll see what I can find!

Thanks again for all the help,

Jim


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## jengele (Nov 1, 2011)

HCBPH said:


> Jim
> I just noticed that the sprocket that takes up the slack in the chain on the left (in this photo) is outside the chain and behind it! Mine is inside the chain and it floats with an arm that extends to the foreground where a spring pulls on it (currently ineffectual). I wonder if mine is intended to be behind the chain like yours? The spring would be the right length then, pulling it into the back of the chain which would take out the slack. The tension from the spring pulling the sprocket into the chain would help pull the friction disk down onto the speed disk. When I get to reassembly, I'll take pictures of this and see if it will work.


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## HCBPH (Mar 8, 2011)

*Friction drive unit*

Jengele

Sounds like your making a good start here. If yours is like mine, it's not rocket science to work on it. The biggest issues you'll have is remembering what goes where and the disassembly process. That's why I take alot of pictures and make drawings or use tape and markers as something is coming apart.
Any roll pins I encountered, if the part would come out without removing it, if it needed to come out I tried to do it after the part was out. If not, I used an hammer and punch and drove them out in place.
When I had mine apart, all the T-Bushings like on the friction plate shaft, where the axel went through the friction disc housing etc all appeared to be compatable with the one I mentioned from B&S. To get them out, I used a long punch, supported the piece and tapped them out from the back side. To put the new ones in, support the piece and used a small piece of wood over the new bushing and tapped them in straight into the receiving part of the item. That upper shaft on mine used the oval shaped bushings like on the axels, the only difference is they only have 1 part of the same clamshell retaining mechanism as on the axels - the other half was the actual sheetmetal of the side panels..
When it came to reassembling the unit, I replaced the rollpins with bolts and safety nuts. I precut some to length so there wasn't too much leftover thread sticking out. It's a whole lot easier to slip a properly sized bolt through the holes than drive back in the rollpins (big hands and all thumbs at times).
I didn't have to take the friction disc off the one I have when I had it apart but I looked at it. Looked like if you took the bushings off the ends of that swing assembly you would work the shaft out. Once out you should be able to do most anything with it. I don't honestly know what bushings it takes there (especially with the hex sided shaft) but I'm sure with a little luck you'll find something if you need it. If you do, look at both Craftsman and probably Roper parts (not sure but I think either Roper or AYP built that snowblower).
If you need a friction disc itself, that's going to take a little more work if yours is like mine. The center opening on mine was something like 2 3/4" with a 6" diameter. I couldn't find one with those dimensions, but I did find one from a Toro with a 6" diameter and a 1 3/4" opening. I had planned to turn the center opening to 2 3/4" and I'd have to redrill the screw holes. Turned out I didn't need it, but it is an option if needed.
The turnbuckle and spring was added because the previous owner had removed and lost the oem tensioning mechanism. Up on the shifter the spring/tensioner for the friction disc was gone and couldn't figure out what it needed. I in turn made my own tensioner, drilled a hole on the the upper section and added the angle iron to hold the other end. Seems to work well and serves the same function as the original, plus that allows changing the amount of tension if needed.

That help any?


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## jengele (Nov 1, 2011)

*disassembly*

"The biggest issues you'll have is remembering what goes where and the disassembly process."

I used ziplock bags for bolts, washers,flanges,bushings,etc and labeled them with a felt pen - left axle, right rear shaft, left panel bolts, etc. the parts really start to pile up. 

"all the T-Bushings like on the friction plate shaft, where the axel went through the friction disc housing etc all appeared to be compatable with the one I mentioned from B&S. To get them out, I used a long punch, supported the piece and tapped them out from the back side. To put the new ones in, support the piece and used a small piece of wood over the new bushing and tapped them in straight into the receiving part of the item"

I haven't gotten the bushings out yet. I'm hoping the T-bushings will come out like you say. I have tried to remove the roller bearings however. They are in there good. I supported the assembly on wood blocks with a hole in the middle and I used a wooden 1" dowel in the arbor press. I decided to push both bearings out the same way with the press. The first bearing moved down with a horrible creaking sound until it butt up against the other bearing. Then my wood dowel started to crack so I stopped and decided I will have to use a metal dowel to continue pushing. I'm at work and I have a lathe so I can turn down a brass rod to fit. The insides of the bearings are gone, the rollers are gone, all that remains is the steel casing (I think it's stainless) and on one of the bearings the flange has disintegrated as well so I can really only push them out one way, so my dowel has a good flange to press on. The flange is imprinted with "Bremen USA JV121" I'm hoping that is a clue to finding a new bearing. I'm a little worried about stepping up the force to drive them out. The aluminum is cracked around the bearings (they haven't opened up as I've been pushing them out as far as I can tell) Maybe I'm wrong to try to force both out the same way. I'll post pictures as soon as I am able.

"That upper shaft on mine used the oval shaped bushings like on the axels, the only difference is they only have 1 part of the same clamshell retaining mechanism as on the axels - the other half was the actual sheetmetal of the side panels.."

Mine are like that too. The 2 axle bearings and the 2 upper shaft bearings are all the same part number and are available online from sears (with a manufacturer substituted part)


"When it came to reassembling the unit, I replaced the rollpins with bolts and safety nuts."

I picked up some new roll pins, I don't know what's special about the "Drive-Lok pin" that is on the large gear on the axle? I suppose I'll try the bolts like you did on that one in particular.

"I didn't have to take the friction disc off the one I have when I had it apart but I looked at it. Looked like if you took the bushings off the ends of that swing assembly you would work the shaft out. Once out you should be able to do most anything with it. I don't honestly know what bushings it takes there (especially with the hex sided shaft) but I'm sure with a little luck you'll find something if you need it. If you do, look at both Craftsman and probably Roper parts (not sure but I think either Roper or AYP built that snowblower)."

I think I'll leave that alone this time, I've bit off a big chunk here my first time. And besides, It was the first thing that came off with only two bolts. I can remove it easily in the future to fix it up when necessary.

Oh, I picked up Mobil 1 synthetic grease. Is this good for installing inside the bushings and bearings? Also, I have an oil fill hole in the auger gear box(I've never noticed it before) what kind of oil would you put in there?

What kind of grease would you put on the hex shaft for the friction disk?

thanks again,

Jim


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## HCBPH (Mar 8, 2011)

*Repair*

Jim

I'm guessing you have a bearing on the friction disc assembly, but I'm not sure. I didn't encounter a single bearing in the one I rebuilt in any part I disassembled. If you have some bearings, get some digital calipers and most of the bearing houses have most everything available as long as you have the dimensions on them. That's what I did on the pulley shaft on the auger housing: around $40 through Sears for the whole piece and maybe $5 - 10 for the actual bearing through a bearing supplier.

If you have something giving or cracking trying to remove a part, best to slow down and take a 2d or 3d look at it. Maybe add some penetrating oil or even a little heat to loosen it up first. Don't know how easy parts will be to find otherwise. One other thing I've done is cool something down then hit the outside with a propane or Mas torch to warm it enough to easy the parts seperating. Same thing on reassembly, some times cooling one part and warming another makes assembly easier.

If you can get some photos and description of where the problem piece is and where the part goes, hopefully we can give you some tips on fixing it.

As far as the roll pins vs bolts I used: I had a heck of a time trying to line everything up inside the tractor unit and attempt to drive in roll pins. Even using a correct sized punch from the back side didn't help alot. I just grabbed the calipers, started checking various bolts in the bucket till I found one that was the right diameter and used that instead. Things like that drive sprocket I couldn't get the shaft out untill the sprocket was seperated from the shaft. Unfortunately its easier to get it apart than put it back together in a confined space, so bolts worked and that's what I used.

As far as grease goes, I use white grease mainly because it's suppose to work at low temp and I have it on hand plus it was listed in a couple of the owners manuals to use that. Long as your grease works at the temps you encounter, I really don't see a problem with it.

On auger gearbox lube, all the ones I have where I have the manuals say to use 30W oil so that's what I've been using. Some people use others, and some mfg recommend other weights or types. So far I have not had an issue with 30W. One machine I bought the PO had pumped the gearbox full of moly grease, might not have been bad except the gear had pushed it all to the side so I really don't know how well it was lubing the gears, especially in cold weather. The gears were ok, so when I rebuilt it, I used 30W in that one too.

Keep us posted on your progress.

Paul


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## jengele (Nov 1, 2011)

*disassembly*

Well I got all the bushings out. I turned a brass rod to fit inside the bearing casings (the two roller bearing type) and to have a shoulder to push the casings out with an arbor press(the first photo). The other 4 flanged bearings came out much easier pushing them out using ordinary bar stock in the arbor press as well.
As you can see in the photo, the aluminum casing is cracked. It was cracked before I pushed the bearings out but it did open up a bit from my work. I probably should have heated things up but I'm a little inexperienced here and I got impatient. There are a few more small cracks on that same end as well that are hard to see in the photo. I measured the ID on this hole and it is really bell mouth where it is cracked. I decided to swedge this area down using a 2" brass rod stock we had lying around. I bored a recess into the brass to a diameter of 1.260" (the aluminum flange was 1.280" at it's widest) and I bored a 20 degree chamfer on the end of the brass so that the larger aluminum flange could be drawn in to the hole. Then I took this to the arbor press and lubed it up and forced it onto the aluminum. It worked but It was still bell mouth a bit so I turned the brass stock again to be 1.245" and forced it onto the aluminum casing. This really swedged it down, the last photo shows the swedged aluminum and the 2" swedger behind it. The ID of the aluminum is now a little under 1" just at the end, the rest of it is about 1.002". 
What I plan on doing now is to turn an aluminum collar that will fit over the cracked casing. I think I will epoxy it in place and/or push it on with the arbor (do you think epoxy will stand up or should it be soldered/brazed?). Then I can come back with a 1" mandrel and open up the part that I swedged so I can fit a bearing into the casing. (I'm used to working with non-ferrous metals as my day job is a brass instrument repair tech)

I have the oval axle bearings on order but I have yet to order replacements for this aluminum assembly. I will look into the B&S bearings Paul suggested should work for the flanged bearings. You know, I wonder if they would work for the vertical shaft as well? It's a 1" hole with a .75" shaft, if that's what you've got on your machine Paul, might that work in this case as well? 
I've been wondering about bearing dimensions and the kind of tolerances they are designed for. Have you had any problems installing new bearings where the casing has opened up too much? I'm hoping the new bearings will have to be pressed in and will work like new!
btw, regarding the flanged bearings. 1 of them had an ID of .78". I'd say that was pretty worn out for a .75" shaft.


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## HCBPH (Mar 8, 2011)

*Repairs*

I didn't expect to see an aluminum housing but that's not the end of the world.
Cracked aluminum could be heliarc'd or as you said use a collar to reinforce it. I suppose you could even use something like a hose clamp.
If you're going to consider epoxy, consider JB Weld instead. I've used that on a number of old woodworking machine rebuilds, when the situation demands something like that, JB Weld has worked great for me.
I don't see any reason why those bushings wouldn't work in a vertical position, horizontal or anything in between. They are a 3/4" ID and IIRC 1" OD. Those were actually for a Tecumseh Auger gearbox but they worked just fine in the drive section of that machine I had the pictures on.
Here's a couple of tricks I've either used or seen someone else use. There's a thick Loctite that I've seen used on the outside of bearings where the receiving opening has too much play. It was used to help lock the bearing in place and apparently works. I've also seen JB Weld used as a thin coat on the outside of a bushing or bearing, with the same intent. Another I've seen used was the OD on a bushing knurled to increase the OD alittle if it was close but not snug in the opening. Another one where pressing 2 things together, put the receiving item in the oven at 150-200 degrees to warm it up and the bearing into the freezer to shrink it. Or reverse that if trying to get a shaft into a bearing.
Most of the axels and auger shafts I've had to put new bushings on were rusted enough the bearing or bushing wouldn't slip on. I have a knotted wire brush in an angle grinder I go over the shaft with to get all the rust and grime off. I follow that up with some emery cloth to clean it up so the bushing slides on. Once it's in place, areas that are open and don't have something immediately touching, I like to use Rustoleum primer and paint to protect them. On axels and auger shafts where there's an auger or wheel on it, I use plenty of grease to add further protection from rust.

One more thing, I was at Fleet Farm (includes farm products), a store here last weekend. I found alot of different size bushings there, both T type and straight. If you need something, that might be a source for you but better if you have something comparable in your area.

Paul


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## chevyman_de (Oct 2, 2011)

Since you have a lathe you're able to make adapter tubes to install polymer bearings. Igus is the company of choice for those bearings.
igus® - Plastic Bushings, Linear Guides, Cable Carriers, Continuous-Flex Cables
Excellent products and a great company with outstanding customer service. Ok, my personal experience is with the German headquarter only. But I believe the US division will be on par.

Their bearings are way beyond ordinary cheap plastic bushings, the're really a hightech product. Much better than bronze bushings for this application. I highly recommend to give that company a call regarding their recommendation for the right bearing material.


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## jengele (Nov 1, 2011)

That is really helpful information! I've used Jb weld, that sounds good. I was worried about the new bearings being loose and I didn't have any ideas. Also, cleaning up the axles with a steel bristle wheel sounds like a good idea. I'm going to scrub everything down with degreaser in a rubbermaid tub. We have a " tractor supply company" here. I wish we had a fleet farm or farm and fleet or menards but we don't. I haven't had a chance to look for flanged bearings yet, maybe tonight. 

Once again, thanks for the help,

Jim


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## jengele (Nov 1, 2011)

I'll check out igus bearings, but it looks like the flanged bearings I pushed out are a steel alloy. They are hard and heavy and shiny steel looking. The bearings that blew out on the speed disk shaft were stainless steel roller bearings. The flanged bearings have held up quite well considering the age of this machine and the abuse it got here in new England. I certainly do not want even high tech plastic on this short shaft. I'm concerned that bronze isn't even tough enough, the stainless roller bearings didn't do well. but I really don't have the experience to tell.


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## jengele (Nov 1, 2011)

My flange bearings are:

3/4" ID, 1" OD ,1 1/4" long, the flange is 1.260"

These look good at mfgsupply.com :

9-3222 - MTD 748-0169 Bearing | MFG Supply

graphite impregnated 3/4" ID, 1" OD, 1 15/16" long and a 1 1/8" flange

Graphite impregnated, could that be what mine are because they look like steel but they couldn't be because they'd rust to the shaft if they were, right?

The extra length would help lock them in because they would be contacting virgin material inside the aluminum housing. A little JB weld near the opening for a filler if need be.

This is what my other bearings looked like (I think, before they totally disintegrated. I had lots of little needle bearings falling out as I took it apart):

Needle BRG, Drawn Cup, Bore .75 In, .75In W - Needle Bearings - Bearings - 4XFJ4 : Grainger Industrial Supply

Needle Roller Bearing, Drawn Cup, Bore Dia. 0.75 In., Outside Dia. 1.00 In, Width 0.75 In, Max RPM 14, 700, Dynamic Load Capacity 3440 Lb, Static Load Capacity 4968 Lb, Temp Range -5 - +212 F, Cage Material Steel

Why would they have used these? What is the advantage over the flanged bearings? I think I might try these, we have a grainger nearby and they won't break the bank, but I'd like to know the reason for using them, I've seen the disadvantage, but I'm still leaning towards using a similar product because it is available.


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## jengele (Nov 1, 2011)

*bearings*

Here are the IGUS bearings from Grainger:

Flanged Bearing, 3/4 IDx3/4 In L, Pk 5 - Linear Sleeve Bearing - Linear Motion - 2NCL3 : Grainger Industrial Supply


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## jengele (Nov 1, 2011)

I checked out grainger and picked up 2 needle roller bearings, $7 each #4xfj4. I also looked into the IGUS bearings. They were not in stock but I didn't realize that they come in a pack of 5 for $11. If they are appropriate then I might use them, I still am worried that they won't hold up to the abuse they'll get and I'm leaning towards something like an oil impregnated bronze or the graphite impregnated from mfg.


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## chevyman_de (Oct 2, 2011)

jengele said:


> If they are appropriate then I might use them, I still am worried that they won't hold up to the abuse they'll get...


Those you linked to would be the wrong choice. They are from one of the product lines for less demanding applications. The T500-series bearings are much better, but also already way more expensive (2 for $ 21).
Flanged Bearing, 3/4 IDx3/4 In L, Pk 2 - Linear Sleeve Bearing - Linear Motion - 2MTE7 : Grainger Industrial Supply
Their load rating is 6-times as high as for the R-series, for loads up to 21,750 psi.
The ultimate choice would be the Z-series. Load ratings same as the T500, but


Igus-website said:


> extremely high compressive strength coupled with high elasticity enables iglide® Z bearings to attain their prominent features in association with soft shafts, edge loads and impacts.


Don't find them at Grainger, but you can contact Igus directly. They may be even more expensive then the T500's.

Those bearings (T500 / Z series) have a smaller OD at 7/8", so you would have to machine some adapter tubes. The tubes could be glued into the gear case providing a repair and a reinforcement at the same time.

Edit: The needle bearings can't take any axial load and definitely need a hardened shaft with a very smooth surface.


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## jengele (Nov 1, 2011)

*axle*

My axle is bent. I'd like to straighten it by putting it in a vise and putting a long pipe over it for leverage. Do I have to worry about snapping it off? It's bent right at a hole and I'm concerned that its been hardened and if I push too hard with leverage that it will just break, am I over thinking it? 

I still have to get flanged bearings and I'm concerned about the needle bearings, ill decide what to do later.

On the weekend I found some time to degrease some parts and the housing for the transmission. I'm concerned about some of the rust and also, leaving all the steel parts like pulleys and shafts and gears to rust up. Also, do you guys recommend cleaning the chains in degreaser? What should I lube them with after degreasing and drying them or should I do that at all?


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## jengele (Nov 1, 2011)

*axle*

Maybe I should just leave it alone, what do you guys think?


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## Shryp (Jan 1, 2011)

That is a tough one as you do run the risk of snapping it. On the other hand, that will probably bounce around a lot when using it that way. Suppose if you do snap it you could have a machine shop make a new one, but that won't be cheap.


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## jengele (Nov 1, 2011)

What would it hurt to leave it alone? On the other hand, I have a lathe, drill press, centering tools, cutoff bandsaw, etc. I could make one myself. I don't know what alloy steel to get (I'd probably order from MSC). It's just 4 holes, and 4 grooves for E clips. the holes are chamfered. I'd have to send it somewhere to be hardened. I don't know how much that would cost, I've never done that before, I usually just work with non-ferrous metals.


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## jengele (Nov 1, 2011)

It just ocurred to me that the bent axle might have been part of the problem with the bearings. Could it have put undue stress on the aluminum housing that contained the axle and the vertical shaft that had the needle bearings? Maybe it bounced it around and stressed out the needle bearings to a point of failure?


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## jengele (Nov 1, 2011)

I just found a steel rod .750" lying around the workshop. I don't know what alloy it is but I could use it. Do you guys know of any reason why not to use an unknown steel alloy? It's a little rusty but not nearly as worn out as my existing axle. My axle measures .7355" (at the smallest most worn out spot) and this new rod measures .7480"


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## chevyman_de (Oct 2, 2011)

jengele said:


> ...and this new rod measures .7480"


Seem to be a tad on the small side. The Igus webside wants a shaft diameter between .7479" and .7491" for their plastic bushings. And plastic bushings are usually more forgiving then bronze bushings or even needle bearings. Your bar stock is .7480" with some minor rust. After some rust removal you will be definitely out of specs straight from the beginning. Sure, way better than the old shaft; but I would still look for a different rod. No such shortcuts for a quality rebuild. 

You may take a look at McMaster-Carr


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## jengele (Nov 1, 2011)

I've cleaned it up with scotchbrite pads and I've measured more carefully with a micrometer. It's cold rolled steel, there are some drawing lines down the length of it. The measurements I get are mostly .7485" but some are as little as .7475" and up to .7495" 
I don't know if I could get something more accurate out of cold rolled steel. I just looked up MSC and they have 36" drill rod (water hardening), ground to .750" +-.001" for $17.84. That would be much better.

I measured my replacement bearings from Sears with a snap guage and a mic and I am getting .7548"


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## chevyman_de (Oct 2, 2011)

jengele said:


> I measured my replacement bearings from Sears with a snap guage and a mic and I am getting .7548"


Bushings will get their final inner diameter *after being press-fitted* into the gear case; the current diameter has little meaning.


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## jengele (Nov 1, 2011)

The bushings I measured are the ball shaped ones. They have a steel flange (one on the inside and one on the outside) that is bolted to the side wall of the blower. These bolts tighten laterally to the bushing and they are not press fit into anything. I don't think the ID will shrink at all on these ones. The flanged bearings, yes, you make a good point, but I don't have them yet to measure. I was concerned that if I get the drill rod (which could be .751" at the largest) it will be too tight a fit for the flanged bearings. You previously quoted the Igus website saying the shaft should be no larger than .7491"


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## jengele (Nov 1, 2011)

I just called www.countyheattreat.com in Milbury, MA. He recommended 8620 steel, second 4142 but he also said cold-rolled would work fine as well as it's not a high speed application. He preferred cold rolled to the water hardening type I suggested out of MSC given that it will be used as a snowblower axle. He said he could keep the shaft straight to within about .015" for a 3/4" by 26" shaft. It would cost about $125 just to harden it.


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## HCBPH (Mar 8, 2011)

*Shaft*

Jengele

Looking at that axel, I'd think any competent machine shop could heat and straighten it without a problem.

With the equipment you have, I don't see a reason you couldn't duplicate it if you want. Where you're going to have to be exact is where the shaft has to slide through the bushings on the friction disc assembly, the sprocket and collar along with the respective roll pin holes, the two outside bushings, the 2 eclip slots and where the wheels fit and bolt down.
I guess what I'm saying is the diameter has to be correct the entire length. Here's one of mine and yours should be comparable, this is a before picture where the axel bushing clamshells were installed incorrectly by the P.O.
















It's kind of hard to tell, but here's where the clamshells are properly mounted on the outside of the tractor unit chassis








The bushings on the friction disc assembly proved to be the tightest fit on this one, so that's probably the most critical dimension.

The ones I've worked on are easy enough to work with a file so I don't think it's hardened steel. In fact, if you spin a piece of replacement steel in lathe, I wouldn't be surprised if you couldn't dress it down to the correct dimensions in a relatively short time.


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## chevyman_de (Oct 2, 2011)

The diameters on the Igus site are for their plastic bushing, not for bronze bushings/neeedle bearings/ball bearings. McMaster lists a tolerance of 0.0" to -0.001" for their shafts which is fine for those applications. Maybe I would go for their chrome plated shafts. You could remove the chrome with a dremel where you have to machine the shaft, but still have the hard surface for the bronze bushings.
A +0.001" shaft would be ok for bronze bushings with an inner diameter of .7548".

No chrome plated shafts for needle bearings without inner ring, a hardened shaft is the only way to go here!

125 bucks just for hardening one shaft is a rip-off in my opinion. It's not for a space shuttle after all.


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## jengele (Nov 1, 2011)

"125 bucks just for hardening one shaft is a rip-off in my opinion. It's not for a space shuttle after all. "

That's what I thought. I'm going to shop around.

Paul, are you suggesting that the axle might not need to be hardened at all? 

I hadn't considered taking the bent one to a shop that could straighten it. That might be a good idea, but it is awfully worn down and uneven. If I can make a new one out of this cold rolled steel rod I'll be way ahead of the game I think.


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## jengele (Nov 1, 2011)

All I need to do to make a new one is to cut it to length and clean up the ends. Turn 4 grooves in for E clips and 4 holes. The 2 grooves and 2 holes that are on the ends are for holding the wheels on. They don't have to be really precise, there is a lot of room for error there. The two inner holes and two grooves need to be more precise and they need to be measured not from the end of the shaft but from each other as well. for the grooves I will use a 1/16" cutoff tool. The holes will be more challenging but if I can position them correctly I can do a good job.


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## jengele (Nov 1, 2011)

Paul, I can see what you are talking about in the photos. I can get the spacing very close to the old shaft. I'm going to have to clean up the rest of my parts and do a mock up fitting and see if everything will slide on. I just turned the grooves and they are within about .005" give or take of the ones on the old shaft (when I line up both shafts side by side and compare all four grooves). the holes will be harder to get correct. I have to measure the edges of the holes and divide by two to get the center of the hole. there's a lot of error I could introduce just trying to get the new holes laid out. I still think I could get the holes within maybe +/- .010" I might be dreaming but we'll see.


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## HCBPH (Mar 8, 2011)

*Axel*

Jim

You're making it too hard. Get the right diameter steel (not hardened), a little long. Start with a V-block to support it while drilling. Mark and drill 1 hole. slip a bolt through both the old and new, either just mark or use a transfer punch to mark from old to new. Drill it. Keep going till all 4 holes are done. Cut the grooves for the E-Clips. Get yourself a mixed bunch of 3/4" shims. Cut your new axel to length. Insure it will slide through all the bushings, gears, wheels etc. Most bushings in good shape won't fit over the shaft if they're in good shape and the axel has already been painted, grease the friction disc assembly bushings and slip it into the tractor unit, get the bushings in there and tape it off and paint the shaft (you'll rub any paint off if done before main assembly). At some point you need to attach the sprocket and collar. Add any additional shims between the E-Clip and the axel bushings to get the sprockets and chain to line up with a minimum of horizontal movement. Grease it well and assemble it.

You're pretty much done here. You're not building a Rolls Royce or a rocket, fix it to work and it will likely outlast you. Tight tolerances are actually something that can work against you. You want a little horizontal play, I'd say 1/16" is just about perfect for that. I wouldn't go any looser than maybe 1/8" if you can help it.

That's it.

Paul


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## kb0nly (Sep 22, 2011)

I second HCBPH's recommendation...

Just make a simple new one it ain't rocket science!!

I definitely wouldn't put the bent one back in, you will just ruin everything your replacing with use. You could heat and straighten it to, i don't see it causing that big of a deal, there just isn't enough stress here to worry about.


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## kb0nly (Sep 22, 2011)

On another note... I wonder how it got bent... Dropped??


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## jengele (Nov 1, 2011)

*axel*

That's the kind of advice I'm looking for Paul! Good stuff. I'll drill the first one and bolt it together to indicate the others. It may be common sense and simple but if you've never done this before, it isn't common or simple! I was looking for advice on painting it as well, thanks for that.

I don't know how it got bent, we get some wicked ice and snow and I'm knocking it around pretty good, but I also bought it used about 5 years ago, who knows.


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## Shryp (Jan 1, 2011)

I would think it was either dropped off a truck or bounced down some steps.


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## HCBPH (Mar 8, 2011)

*Bent Axel*



Shryp said:


> I would think it was either dropped off a truck or bounced down some steps.


Got a nickle says the chain to the axel either was loose, too much horizontal play, etc and when it was running the chain tried to climb the teeth on the sprocket till the engine died or the belt started slipping - end result was the shaft bent at it's weakest spot under tension, where the hole for the sproket attached. 

Only reason I'm confident on that, still have the chain from one that tried to do it also (has a nice twist in the one link). Didn't bend the axel or sprocket but there's definite marks on the chain from when it had jammed. Plus when I bought it, the wheels kept jamming when I tried to roll it to the truck. When I took it apart it became very apparent what was going on. You could have removed at a minimum 1 link from the chain (did I mention it broke the tranny mount in the process due to a loose intermediate shaft bolt?). On the one referenced earlier, I'm guessing the chain was long, the tensioner on the side of the tractor worked loose and they ran it that way till it jammed up.

By the way, with the axel bent like that, the drive chain would go from tight to loose every rotation of the axel (in addition to the wobble), so it's good to fix it now.


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## HCBPH (Mar 8, 2011)

*Painting*



jengele said:


> I was looking for advice on painting it as well, thanks for that.


On painting, I'm trying some different things to see what works best. Some I started last winter and the rest I'm starting this year. I had to deal with some previous rust. For that I'm trying 'Rust Bullet' and Eastman's Rust encapsulating primer. This is in addition to Rustolium Red Primer and Ace Hardware's rust prevention primer.
Top coat paint I'm trying Rustolium, Ace's antirust and Plastikote's.
I'm also experimenting with engine and header paint to help protect the engine and exhaust.

If I do more snowblower rebuilds next year, I'd like to get a sandblaster to help on the frontend cleanup. I have a spray gun but it doesn't make any sense to use that at this time till I have a good starting surface, I'm using a knot wire disc and pneumatic sander currently to clean them up then doing a rattlecan paint job on the housings etc.

That pretty much wraps that up.


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## jengele (Nov 1, 2011)

That sounds plausible considering I found the idler disengaged and a lot of slack in the chain. The wheels have on occasion locked up but then freed themselves. I didn't know why at the time.


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## jengele (Nov 1, 2011)

*assembly*

I picked up some oil impregnated bearings from the Fitchburg branch of Eastern Bearings www.ebearings.com They measured my existing ones, gave me advice, really helpful people.

I cleaned, greased and assembled everything. I used Mobil 1 synthetic grease (good down to -40 degrees). I used antiseize on all threaded components. I also removed a nut and bolt from the side panel that was preventing the chain idler from going behind the chain (so that the spring can pull the idler into the chain to remove slack). This seems to be the way it was intended to function as I've noticed from a couple other pictures on this forum. I don't know why this bolt was there, it seems to work better without it. 

However, when I installed the chain on the left, it really added a lot of resistance. For example, with the unit sitting upright and in the neutral position, I have to grab a wheel with two hands and really push in order to make the gear assembly turn. It does turn, but it's hard to overcome the inertia and it takes a little strength to keep the wheels turning, like I said, definitely a two hand job. Without the chain on the left, it turns much easier. I think the spring that pulls the idler might be too strong, with it disconnected, it is a little easier but still harder to turn the wheels than I thought it should be. As I assembled it, each shaft turned smoothly and easily on its own. Is the chain too short? Is this normal?


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## jengele (Nov 1, 2011)

Oh, and there is a little side to side motion on the axle. About 3/8". Is this normal or should I install some washers as spacers to prevent this motion? The gears on the right seem to function fine with this kind of motion but it also seems excessive to me.


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## HCBPH (Mar 8, 2011)

*Wiggle room*



jengele said:


> Oh, and there is a little side to side motion on the axle. About 3/8". Is this normal or should I install some washers as spacers to prevent this motion? The gears on the right seem to function fine with this kind of motion but it also seems excessive to me.


Personally I like to see maybe 1/16"-1/8" side-to-side movement. IMO it would be less likely for the chain to try and jump a tooth if there ever developed some slack in the chain. I just used some shims between the E-clip and the outside of the axel bushing and it seems to work just fine for me.

On setting the tension on the friction disc, here's what I did. First off, remember I didn't have the springs etc up on the handlebar shifter, I had to make my own mechanism but it seems to work fine. I shifted the gear to the highest one and pushed the handle all the way forward. I loosened the clamp on the shifter to the shaft and let the spring pull the friction disc all the way forward onto the friction wheel then tightened the shifter clamp back up while the shifter is still all the way forward. When I pulled the shifter back to disengage the disc, it moved the disc off about 1/8"-3/16" which seems to work just fine. May not be what the manual says, but then again I don't have the manual.


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## jengele (Nov 1, 2011)

*friction wheel tension*

I'm going to have to play with that a bit but I'm not having any problem with that in particular. I'm wondering if the chain on the left is too short and when it's in neutral, the chain is so tight that it's really hard to move the machine. When I shift it into gear, the distance between the two sprockets is closer together and there is slack in the chain, slack that is taken out by the idler sprocket attached to a spring (a spring that I think might also be too tight). Is there cause for concern here? I'm worried there is so much resistance that there will be premature wear somewhere, also it would be nice to move it around easier.


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## HCBPH (Mar 8, 2011)

*Drive chain*

Jim

I see what you're talking about now. Hadn't thought about that being different between yours and the one I have. Mine has an idler that bolts through the side of the chassis to keep some tension on the chain. I put it on the outside of the chain, made the most logical sense because that's where it would be needed the most - in reverse.








If it seems too tight, I'd look into trying a lighter spring. It would only need a very light weight spring if all you did was go forward as it would be on the non-tensioned side of the chain when in a forward gear. When it would really need some degree of tension would be when you use reverse, that's then the side with the tensioner would have the most pull on it and you wouldn't want the other side getting too much slack and trying to climb the sprocket.

If you're into a little experimenting, maybe see about replacing the spring with a solid mount - something like a long bolt threaded the whole length or maybe a turnbuckle for adjustability, kind of like what I did with the spring on the friction disc I set up on mine. Put it so the tensioner sprocket is just taking up the slack on the chain with a small amount of play when in neutral. When you engage the drive, see how much play you have. That might be a working solution also. I put a piece of wire through one eyelet and the middle of the turnbuckle so it won't move with vibration over time, kind of a safety wire type setup.

Just some thoughts.


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## jengele (Nov 1, 2011)

*tension*

That sounds like a good idea. I like the solid mount thing, I'll look into that.


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## Flannelman (Sep 24, 2011)

I have one thats somewhat similar except its got a Idler thats adjustable rather than spring tensioned. Mine had the same problem as yours it was hard to move and I ended up slacking to the limit of the slot. The chain still had plenty of tension on it. I'd see about maybe knocking down the spring size by about half and see what that does. It looks something like a 20lb spring and it probably only needs a 10lb.


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## jengele (Nov 1, 2011)

*idler sprocket tension*

You know, there is an adjustable slot on the side panel. there was a bolt in it as well. The sprocket was positioned inside the chain loop and the adjustable bolt prevented the sprocket from contacting the chain behind it. The spring was too long and prevented the sprocket from being pulled into the forward part of the chain loop. 
I removed the adjustable bolt and positioned the sprocket behind the chain so the spring could pull it to take out the slack in the chain. 
I'll try the lighter spring but I wonder how the adjustable bolt was supposed to work?


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## Flannelman (Sep 24, 2011)

Mine just has the loop running from the drive gear to the axle gear then the idler which is on a bolt in the slot. Mine really could stand a longer slot but I think someone either took a link out of the chain or put on a new one thats shorter. So even though I'm at the loose limit the chain is still plenty tight but I think if the chain stretches some from use it will be right on the money.


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## HCBPH (Mar 8, 2011)

*Chains*



Flannelman said:


> Mine just has the loop running from the drive gear to the axle gear then the idler which is on a bolt in the slot. Mine really could stand a longer slot but I think someone either took a link out of the chain or put on a new one thats shorter. So even though I'm at the loose limit the chain is still plenty tight but I think if the chain stretches some from use it will be right on the money.


If you need another link, that's possible. I have some at home, don't know what they're called but they make it possible to add a single link to a chain.
Look here: Search roller chain link - Grainger Industrial Supply
Look at the 5th item down and you'll see what I'm talking about (may not be the right size, just for descriptive purposes). Hope that helps.


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## jengele (Nov 1, 2011)

*chain*

I was just at an Ace Hardware in Acton, MA. They had a great selection of bronze flanged bearings, all different sizes including the size I needed. they also have a great selection of chain links just like the ones at grainger. Not all hardware stores have this stuff, but just so you know, some do!


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## jengele (Nov 1, 2011)

Ok, I installed an extra link (#41 offset from Aubuchon hardware) . This provided some slack in the chain. I messed around with a turnbuckle and a spring but once the chain was a little looser the original spring on the idler sprocket seemed to work just about right. When the machine is upright and in neutral I can grab a wheel with one hand and turn the drive assembly with a reasonable amount of resistance. When the machine is in gear and contacting the friction plate the drive chain may have a little too much slack and/or the idler spring is too long and isn't taking out all the slack, even so, it works. I'll try to find a slightly shorter spring.


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## jengele (Nov 1, 2011)

I have another issue with the deflector chute cable which adjusts the height. It is broken right where it connects to the adjustable deflector chute. I've looked at hardware stores and they have 1/16" steel braided cable but they don't have any small enough ties (or something like a tie) to form a loop on the ends of the cable. One guy told me that I needed a plastic coated cable so it will slip through the flexible hose that guides it. 

Do I need to scrap the flexible hose and find something like a bicycle brake cable or a coated braided cable to fit into my existing hose and what do you call those fittings that clamp down a loop into the cable so I can form a loop that a bolt can go through at either end of the cable?


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## HCBPH (Mar 8, 2011)

*Cable end*



jengele said:


> I have another issue with the deflector chute cable which adjusts the height. It is broken right where it connects to the adjustable deflector chute. I've looked at hardware stores and they have 1/16" steel braided cable but they don't have any small enough ties (or something like a tie) to form a loop on the ends of the cable. One guy told me that I needed a plastic coated cable so it will slip through the flexible hose that guides it.
> 
> Do I need to scrap the flexible hose and find something like a bicycle brake cable or a coated braided cable to fit into my existing hose and what do you call those fittings that clamp down a loop into the cable so I can form a loop that a bolt can go through at either end of the cable?


If that's the cable with the double loops (1 on each end), first would be try your local parts supplier (take the old one and see if they have one on hand by chance). If that doesn't pan out, try: McMaster-Carr
Look at item #3474T31. I just picked up a couple of them to have one hand if needed. Haven't used on yet, but looks right to me. A little pricey but then again what is it worth to fix that cable? You don't really need it, but it's nice to have functional.

Update: just thought of one more idea. Make a small clevise out of flat metal, bore a hole through the ends to bolt to the adjustable part of chute. In the middle of the bend, drill a hole for the cable to fit through. Use a cable stop to connect the cable to the clevise. I was thinking the other day about the same thing except doing it on the control end. No reason it shouldn't work on the chute end also. Just a thought.


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## jengele (Nov 1, 2011)

HCBPH said:


> ...If that doesn't pan out, try: McMaster-Carr
> Look at item #3474T31...


I like that, I think it would work in my situation!


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