# 536.886331 10hp/29" Craftsman Jack shaft problems



## sock-feet (Dec 14, 2017)

I lent my Track Drive 10/32 to my friend because his blower wasn't working right. I took a quick look and the Jack shaft sprocket assy #34 538010 or Murray number 761789MA is rounded over and the sprocket that is in the hex shaft the friction plate is trashed. The craftsman website doesn't show #26 in the parts list.

Does anyone have a part number for this shaft/sprocket? Does anyone have a good used one that I could buy? I would like to get both parts good used if possible.

I'm not sure why these sprockets went bad. There seems to be a lot of side to side play in the hex shaft#26 and the #41 chains looked like they were never oiled or greased. I think that the the dry chains destroyed the two small sprockets. Thoughts? The machine is in real good condition and I would like to get it going again for my friend.

https://www.searspartsdirect.com/model-number/536886331/0247/1507200.html


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## JLawrence08648 (Jan 15, 2017)

It's not listed as the part is obsolete and not available, part #33112

You may be able to cross reference it to Murray as that is who built your machine. I have a similar machine Craftsman II 10/29, I have 2 Murray's in my yard, levers are different, I will look for you.


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## sock-feet (Dec 14, 2017)

JLawrence08648 said:


> It's not listed as the part is obsolete and not available, part #33112
> 
> You may be able to cross reference it to Murray as that is who built your machine. I have a similar machine Craftsman II 10/29, I have 2 Murray's in my yard, levers are different, I will look for you.


I ordered a 8 tooth #41 sprocket that I could weld on, but I would rather not. I ordered the jack shaft sprocket #34. It was cheap enough on ebay.


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## sock-feet (Dec 14, 2017)

JLawrence08648 said:


> It's not listed as the part is obsolete and not available, part #33112
> 
> You may be able to cross reference it to Murray as that is who built your machine. I have a similar machine Craftsman II 10/29, I have 2 Murray's in my yard, levers are different, I will look for you.


That Craftsman II 10/29 is the same exact machine. Make sure the internal chains are well lubed. I would even check the side to side play on the 33112 shaft-this one seems excessive. The shifter arm also seems to rub on the 33112 shaft, which is the reason that clip in the picture is all mangled. There should be some kind of stop on that arm.


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## JLawrence08648 (Jan 15, 2017)

Three are two Murray parts that may work, #579897 superseded by #585855MA

Amazon $30, eBay $40, JacksSmallEngines $35


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## sock-feet (Dec 14, 2017)

JLawrence08648 said:


> Three are two Murray parts that may work, #579897 superseded by #585855MA
> 
> Amazon $30, eBay $40, JacksSmallEngines $35


Just made an offer on this whole assy.
https://www.ebay.com/itm/Craftsman-...rksid=p2047675.c100005.m1851&autorefresh=true


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## JLawrence08648 (Jan 15, 2017)

I looked at. Whatever you do, that shaft should have a very very very thin coat of synthetic grease. There also may be a grease fitting, you can use any grease for that though I prefer synthetic.


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## Sid (Jan 31, 2014)

Those shaft end bearings are lightweight, they will last a while but will fail usually at a bad time.
Sid


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## HCBPH (Mar 8, 2011)

From what I can see it looks like that sprocket is worn down to the nubs. The only time I've seen something like that was when the sprocket on the other end was sloppy and sliding side to side when in use.
If that's the case, when it's repaired shim the sprockets so they stay in alignment.


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## jtclays (Sep 24, 2010)

HCBPH said:


> From what I can see it looks like that sprocket is worn down to the nubs. The only time I've seen something like that was when the sprocket on the other end was sloppy and sliding side to side when in use.
> If that's the case, when it's repaired shim the sprockets so they stay in alignment.


This is accurate good info. The longer full bucket width jack shafts also wear dimensionally side to side. You can spend time and money replacing the cheap side bushing/bracket/retainers only to have the thing wobble out again. Once you have the new piece in hand you can see the old one actually wore away side to side and was no longer the correct dimension to fit in the machine. My son just did this repair on an 11/30 Craftsman/Murray. The other shaft "upstream" and it's sprocket were out of functional dimension causing the wear. HCBPH speaks with great knowledge and experience as always:grin:


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## HCBPH (Mar 8, 2011)

Here's a picture of one I ran into. It's nowhere as bad as that one but still shows what can happen when the sprocket on the other end has extra play in it. Photo shows one in good condition and another that started getting torn up by slop in the sprocket on the other end of the chain. Notice in addition to the damage on the sprocket how the bushing is chewed up in the sprocket. You have to fix everything or you're just putting a bandaid on the problem.

As it gets worn it in turn can cause damage to other parts of the drive system because of it's inability to work as it should.


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## sock-feet (Dec 14, 2017)

Yes. There is excessive play side to side on the axle and Hex shaft. I am going to make shims to keep all of the play out and keep the chains all in alignment. I am going to clean and soak the chains in oil. One chain seems to be a little stiff from lack of lube and if it looks too bad to resurrect, I will replace it.


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## jtclays (Sep 24, 2010)

From running and repairing about 35 dirt bikes in my youth I know you can keep chains for quite a length of time, even removing links. Eventually the chains wear becomes the reason sprockets wear and the chain itself is the problem, not the parts it turns. Usually if the chain needs to be soaked it's done anyway. Obviously not so critical at the rotation speed of snowblower drives, but a consideration.:wink2:


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## sock-feet (Dec 14, 2017)

You are right. I still have some stainless chain that I might donate to the cause. 

I took a better look and this has so much play in the shafts. They move all over. I think I am going to grind the arm that engages the friction disk down to create more clearance between the hex shaft and arm. I will make some 3/4 " shims for the axle and some for the other shafts when I get it apart.

I cleaned the carb and Lubed all pivot points.


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## jtclays (Sep 24, 2010)

Sock, Just from quick inspection on the pics this bearing assembly is suspect. I redid a Murray built Craftsman that had the same internal housings. We used washers to get the bearings/bushings in more (between the tractor metal and the bearing housing) as a temp fix until we got the new jack shaft assembly. Also worth an eyeball to see if the tractor housing is square. They aren't always and sometimes a medium swift nudge with a BFH corrects a couple years of mistreatment:wink2: We don't need to talk about the friction wheel.


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## sock-feet (Dec 14, 2017)

jtclays said:


> Sock, Just from quick inspection on the pics this bearing assembly is suspect. I redid a Murray built Craftsman that had the same internal housings. We used washers to get the bearings/bushings in more (between the tractor metal and the bearing housing) as a temp fix until we got the new jack shaft assembly. Also worth an eyeball to see if the tractor housing is square. They aren't always and sometimes a medium swift nudge with a BFH corrects a couple years of mistreatment:wink2: We don't need to talk about the friction wheel.


Good points for sure. Which bearing assy is in suspect? I am getting a new Friction disk and other goodies. Do you think the sides of the tractor has bowed out, causing the side to side play?


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## jtclays (Sep 24, 2010)

Don't know why, but this pic shows up 50% of the time, check again and it vanishes. Will try it this way.
Don't know if it's because it's stored in my documents as opposed to my pictures. Trying to move it around a bit. Here's some pics of the damage on my sons Craftsman/Murray. It had the jack shaft going from edge to edge across the tractor body inside dimensions, so quite a different part and torque points. We actually ordered the wrong part originally, and it was the same small sprocket welded to the big sprocket in yours.
After we got the correct replacement we were able to measure to part and the old shaft had actually worn end to end and was functionally too short.


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## sock-feet (Dec 14, 2017)

jtclays said:


> Don't know why, but this pic shows up 50% of the time, check again and it vanishes. Will try it this way.
> Don't know if it's because it's stored in my documents as opposed to my pictures. Trying to move it around a bit. Here's some pics of the damage on my sons Craftsman/Murray. It had the jack shaft going from edge to edge across the tractor body inside dimensions, so quite a different part and torque points. We actually ordered the wrong part originally, and it was the same small sprocket welded to the big sprocket in yours.


Oh Yea. I see. The BFH will need to bash the side of the tractor back together or I could put washers between the bearing and the tractor housing-putting the bushing closer to the Hex shaft.


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## sock-feet (Dec 14, 2017)

I started to take old Betsy apart and the Jack shaft Sprocket assy is a pain in ass to get out the furthest inside bolt. The arm that engages the drive plate is blocking it. Anyone have any short cuts? It looks like I have to completely dismantle the tractor part to get that one bolt out.


:banghead:


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## sock-feet (Dec 14, 2017)

Well I read some of the threads and I used the hold the bolt with a wrench I ground down and turned the bearing carrier. I replaced it the same way. You will need patience. I replaced all of the bad parts and lubed the **** out of all of the moving parts. The one chain was really bad and seized up and I took all of the play out of the shafts. It should last another 20 plus years.

Here are some pics of the worn parts and the finished project.


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## bigwally (Feb 10, 2021)

sock-feet said:


> Well I read some of the threads and I used the hold the bolt with a wrench I ground down and turned the bearing carrier. I replaced it the same way. You will need patience. I replaced all of the bad parts and lubed the **** out of all of the moving parts. The one chain was really bad and seized up and I took all of the play out of the shafts. It should last another 20 plus years.
> 
> Here are some pics of the worn parts and the finished project.


Can you elaborate on how you got that assembly out. I can not get to that deeper in bolt at all. Sounds line you are saying grind away at the bearing holder but am not sure. maybe a misplaced word in the statement?. --> " I used the hold the bolt with a wrench I ground down and turned the bearing carrier."


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## bigwally (Feb 10, 2021)

JLawrence08648 said:


> Three are two Murray parts that may work, #579897 superseded by #585855MA
> 
> Amazon $30, eBay $40, JacksSmallEngines $35


I have moved heaven and earth and can't find this HEX shaft assembly.. Both are discontinued and no replacement. Any suggestions?


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