# HMSK80 runs poor after being worked hard.



## ChrisJ (Nov 27, 2014)

As others may recall I've been chasing a problem. Assumed it was the carb and possibly fuel line. Now I'm running out of ideas.

I changed the sparkplug in my Tec HMSK-80 on the weekend but have not run the machine yet because there's really no point.

The engine was missing under load and opening the main jet only seemed to make things worse.


What do you think the chances are this plug was causing the issue? My opinion is close to none.



I didn't bother starting the engine after changing the plug because this problem only seems to happen after the engine has been working fairly hard for a while. Without snow, I'll never get it to have the problem anyway. New Tecumseh OEM pre-emissions carb, new fuel line, filter and the problem seems to persist.


At this point, I have no idea what would cause a problem only when the engine is good and hot. Runs great before you actually use the machine for 40 minutes or so.

Any ideas?


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## ELaw (Feb 4, 2015)

I agree that plug doesn't look too bad, although for $2.00 I'd try replacing it anyway.

Have you checked valve clearances? Those are temperature-sensitive.

Another possibility is bad plug wire or magneto. Temperature can affect those, and they also could be affected by snow (=moisture) drawn into the engine's cooling fan.


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## ChrisJ (Nov 27, 2014)

ELaw said:


> I agree that plug doesn't look too bad, although for $2.00 I'd try replacing it anyway.
> 
> Have you checked valve clearances? Those are temperature-sensitive.
> 
> Another possibility is bad plug wire or magneto. Temperature can affect those, and they also could be affected by snow (=moisture) drawn into the engine's cooling fan.



Haven't checked the valves, though I probably can.
Whatever I do, I'd like to somehow get to a point where I know I can depend on this thing when the next storm comes. 

It also seemed like letting it run without a load on it for a bit caused the problem to fade until it started working hard again.

Are the valves on these engines adjustable?


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## ELaw (Feb 4, 2015)

ChrisJ said:


> Are the valves on these engines adjustable?


With some difficulty... you have to grind the stems. If you search here there's a lot of discussion about it, and I think there are some videos on youtube showing the procedure.

But *checking* them is fairly easy... you may have to remove the carb & manifold to get access, but then it's just two screws to remove the breather, rotate the engine to the proper position, and use a feeler gauge.


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## ChrisJ (Nov 27, 2014)

ELaw said:


> With some difficulty... you have to grind the stems. If you search here there's a lot of discussion about it, and I think there are some videos on youtube showing the procedure.
> 
> But *checking* them is fairly easy... you may have to remove the carb & manifold to get access, but then it's just two screws to remove the breather, rotate the engine to the proper position, and use a feeler gauge.



This may seem like a really dumb question but how would the stems become too long from use?

I would think the cam / stem would wear more than the valve surface, no?


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## Kiss4aFrog (Nov 3, 2013)

The clearance decreases as the valve seat and bottom of the valve wear.

https://www.google.com/#q=youtube+checking+tecumseh+valves


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## Dave C (Jan 26, 2015)

ChrisJ said:


> This may seem like a really dumb question but how would the stems become too long from use?
> 
> I would think the cam / stem would wear more than the valve surface, no?


No... The exhaust valve burns into the seat over time and the clearance between the lifter and valve stem tip gets smaller. Things expand with heat and the problem gets worse as the machine warms up.

You will need to remove the muffler and intake manifold to get to the valve cover / breather. The gaskets are cheap to replace.


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## ChrisJ (Nov 27, 2014)

Something else I didn't realize until just now.
These valveseats are aluminum, aren't they?

Sounds like everyone think's there's a good chance it's the exhaust valve?
Is this common on an engine that doesn't have that much time on it?

Should I buy a valve grinding tool for it while I'm at it, or no?


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## Dave C (Jan 26, 2015)

The valve seats are in the cast iron block. The aluminum head is just a cover for the combustion chamber. The intake valve is usually ok, it's the exhaust that wears. I doubt anybody bothers to cut new seats, just lapping is good enough.

If you find that the valve lash needs adjustment, you'll want to get a new head gasket too.


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## 43128 (Feb 14, 2014)

its more than likely the exhaust valve, the stems expand when the engines get older, happened to my hm80 and i threw it on cl for parts and got a honda clone


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## ChrisJ (Nov 27, 2014)

Dave C said:


> The valve seats are in the cast iron block. The aluminum head is just a cover for the combustion chamber. The intake valve is usually ok, it's the exhaust that wears. I doubt anybody bothers to cut new seats, just lapping is good enough.
> 
> If you find that the valve lash needs adjustment, you'll want to get a new head gasket too.



The HMSK is an aluminum block with a cast iron sleeve, no?

Sounds like I need :

*
Head gasket
muffler gasket and bolts
valve lapping kit?
valve cover gasket
*

Starting to wonder if I should've bought a predator engine now........


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## 43128 (Feb 14, 2014)

ChrisJ said:


> The HMSK is an aluminum block with a cast iron sleeve, no?
> 
> Sounds like I need :
> 
> ...


thats what i would have done. people think im crazy to replace a tecumseh with a clone but when you see how much it costs to rebuild one without labor
costs added they understand my decision, especially consideringthe tecumsehs were terrible engines in the first place. cut your loses and part it out on ebay. get rid of it


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## ChrisJ (Nov 27, 2014)

43128 said:


> thats what i would have done. people think im crazy to replace a tecumseh with a clone but when you see how much it costs to rebuild one without labor
> costs added they understand my decision, especially consideringthe tecumsehs were terrible engines in the first place. cut your loses and part it out on ebay. get rid of it



My only disagreement with this is we still don't know how well those Predator engines hold up under heavy use. No one has had one of these in use a lot for 10+ years yet my dad has an HMSK-110 he's been using since the mid 90s.

Do they even have a cast iron bore? Must be a reason the better engines for snowblowers and generators have a cast iron bore, no?


The main thing that put me off about them though, was having to find a new pulley and modify things to mount it on the blower.


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## ChrisJ (Nov 27, 2014)

Scratch that,

At least looking at the 8HP Predator, it DOES have a cast iron bore.

Sigh


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## RedOctobyr (Mar 2, 2014)

ELaw said:


> Another possibility is bad plug wire or magneto. Temperature can affect those, and they also could be affected by snow (=moisture) drawn into the engine's cooling fan.


I've also heard about intermittent ignition problems as things get hot. Maybe you could check the spark under normal conditions. 

Pull the plug out, lay it against the head (so the outside of the plug is grounded), pull the cord, and see if you get a bright blue spark (may not be very visible in the sun). 

Get it to reproduce the problem, then repeat the test. 

Alternately, you can get inline ignition testers, they flash when the ignition fires. You could leave one of those connected, and see what it looks like normally. When it starts to have trouble, see if the flashing is cutting out, etc. 

But this is all predicated by being able to reproduce the problem, unfortunately. I don't know a good way to add a load in warm weather. Someone mentioned running the bucket in a few inches of water, and having it throw the water. It's an interesting idea, at least. I doubt the augers would care much about some water, but get it into the impeller, and I'll bet you'd be able to load up the engine. But for a half hour? Maybe not. 

At least check the valve clearances, though. It's easy to do, and if the clearances are too small, that might point to a problem. With the head off, you should also be able to look at the valve seats, to see if they are worn, etc.


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## 43128 (Feb 14, 2014)

all of the predators have a cast iron bore and dual ball bearing crankshafts. i love mine and my 196cc clone and would never fix a tecumseh again if it had more than carb issues unless i happened to have a good used block in my parts bin


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## 43128 (Feb 14, 2014)

same engine toro uses in their single stage machines


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## ChrisJ (Nov 27, 2014)

43128 said:


> same engine toro uses in their single stage machines


With all due respect,

"Single stage Toro" doesn't exactly scream heavy duty to me.

Maybe I'm way out of line, but that's my current perspective.


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## 43128 (Feb 14, 2014)

the way i see it a huge company like toro wouldnt use an engine without extensive testing


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## ChrisJ (Nov 27, 2014)

43128 said:


> the way i see it a huge company like toro wouldnt use an engine without extensive testing


Very true, and a good point.
But any single stage machine is considered light duty, no?


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## ChrisJ (Nov 27, 2014)

Since we're on the subject.
Who actually makes the Predator engine because that seems to be a HF name.

Can they be bought anywhere else under another name?


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## ELaw (Feb 4, 2015)

43128 said:


> the way i see it a huge company like toro wouldnt use an engine without extensive testing


U mean like how Ariens used those Tecumseh engines you describe as "terrible" for 40+ years?


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## ChrisJ (Nov 27, 2014)

ELaw said:


> U mean like how Ariens used those Tecumseh engines you describe as "terrible" for 40+ years?


That's just because the Tecumsehs were actually pretty good engines for their day.

I'd assume we see a lot of problems just because of the huge quantity sold and the machines they are used on (often ignored, sit for many years etc).


I have a much bigger dislike for many Briggs engines I've had with awful plastic vacujet carburetors on them. Complete junk.


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## 43128 (Feb 14, 2014)

loncin makes them. i have had many tecumsehs in my lifetime and i have never had a 4 stroke one run right, including ones that were owned by my family since new and have had proper maintenance done on them. ive also had a 2 stroke tecumseh in a craftsman single stage, never ran right and would always develop a surge every year even after proper storage(gas removal cylinder fogging). single stages are considered light duty, but that doesnt mean the engines arnt heavy duty. the only single stage snowblower i would call heavy duty are the honda hs521s and hs621s


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## ChrisJ (Nov 27, 2014)

Is Loncin also who makes Generac's brand of engine that looks like a Honda ripoff?


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## 43128 (Feb 14, 2014)

yeah, they also build for toro and trhe carting community. almost any 212cc clone you see is a loncin


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## ChrisJ (Nov 27, 2014)

43128 said:


> yeah, they also build for toro and trhe carting community. almost any 212cc clone you see is a loncin


Question is, are the ones Generac is using the same as what HF is selling for pennies.


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## ChrisJ (Nov 27, 2014)

Loncin Honda clones.. Any good? - boards.ie


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## Kiss4aFrog (Nov 3, 2013)

There are many threads for and against anything. There are many members here that like their Predator, Greyhound, ... powered blower. I haven't found anyone on here who's re-powered a blower and was dissatisfied with their predator.

It's up to you to make a decision on rebuilding the Tec or going with something else new or used.


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## ChrisJ (Nov 27, 2014)

Kiss4aFrog said:


> There are many threads for and against anything. There are many members here that like their Predator, Greyhound, ... powered blower. I haven't found anyone on here who's re-powered a blower and was dissatisfied with their predator.
> 
> It's up to you to make a decision on rebuilding the Tec or going with something else new or used.



I hate decisions like that.
I made a few before and look what happened. 

Wonder how the Honda GX200 on my pressurewasher that I really don't need would work on the 24" Ariens?


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## Kiss4aFrog (Nov 3, 2013)

The GX200 would be great for the blower.


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## 43128 (Feb 14, 2014)

that would be a great choice


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## RedOctobyr (Mar 2, 2014)

Or for ~$100 you could keep your pressure washer functional, and get the 212cc Predator. Something to consider. Heck, sell the pressure washer for >$100, and also buy a Predator


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## ChrisJ (Nov 27, 2014)

RedOctobyr said:


> Or for ~$100 you could keep your pressure washer functional, and get the 212cc Predator. Something to consider. Heck, sell the pressure washer for >$100, and also buy a Predator



Yeah, but then I'd have a cheap knockoff of the engine I already have.


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## 43128 (Feb 14, 2014)

yeah, but then you get a new engine to mess with. what im really waiting for someone to do is pull the governer, install a billet flywheel and rod, and a 22mm mikuni on a predator and bolt that ****** on an ariens 24 inch and see what it can do


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## Kiss4aFrog (Nov 3, 2013)

And an inexpensive, reliable Honda clone to replace the exploded Tecumseh.


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## 43128 (Feb 14, 2014)

by the way the generac engines are the same engines that hft sells just with different colored levers and different shrouding. the ones on generators also usually have a fixed throttle. wouldnt be surprised if the generator heads hft and generac are using were the same


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## Kiss4aFrog (Nov 3, 2013)

43128 said:


> yeah, but then you get a new engine to mess with. what im really waiting for someone to do is pull the governer, install a billet flywheel and rod, and a 22mm mikuni on a predator and bolt that ****** on an ariens 24 inch and see what it can do


IMO, It likely wouldn't do much except wear out bearings and especially sleeves if you didn't upgrade to 100% bearings  

Speed doesn't give you a benefit past a certain point. Going a little bigger on the drive pulley or upping a modified engines RPM will give you some increase. But if the impeller is spinning really fast it would be spinning too fast to load up. Rather than a solid stream of snow coming out you'd have powder blowing in your face and the machine eating through the stock parts like candy.


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## RedOctobyr (Mar 2, 2014)

But if you increased the RPMs beyond 3600, you could go to a *smaller* engine pulley, and keep the rest of the parts turning at a more-normal speed. But be making more power, and have more effective torque to the augers, with the smaller pulley.


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## 43128 (Feb 14, 2014)

http://www.nrracing.com/product-p/mikuni-22mm-kit-gx200.htm

Rod, Connecting, Billet, Predator, 3.595 (for use with Wiseco Piston)

Flywheel, Billet, 6626 - 212 Predator (New Style), Kohler 212

Piston Forged, Wiseco, 2.756, w/Rings (PREDATOR)

also need the engine itself
whos wants to build it


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## 43128 (Feb 14, 2014)

whats the stock pulley size on those ariens anyways?


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## Kiss4aFrog (Nov 3, 2013)

My '75 is about 3.7"


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## ChrisJ (Nov 27, 2014)

At this point why play games?
Let's just switch over to a nice two or four cylinder engine and get it running really smooth too.



On a serious note,
There does seem to be, in my opinion, a huge problem with switching to another engine.

The Predators can't run a headlight and neither can my Honda GX200 without well over $100 in parts.


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## Kiss4aFrog (Nov 3, 2013)

The 212cc can't but the ones with starters can. They aren't $99 which is the big draw for using a Predator in the first place.

The predator would be reliable as would the Tecumseh once you rebuild it.

13hp $299 with coupon 13 HP (420cc) OHV Horizontal Shaft Gas Engine EPA/CARB
This is what I'm thinking of doing for my new 832 Ariens with the ventilated block.

Does your Tec have a lighting circuit and if not have you looked up how much it would be ??
Checked Ebay for used flywheel and stator parts for the Honda and Tec ??


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## ChrisJ (Nov 27, 2014)

Kiss4aFrog said:


> The 212cc can't but the ones with starters can. They aren't $99 which is the big draw for using a Predator in the first place.
> 
> The predator would be reliable as would the Tecumseh once you rebuild it.
> 
> ...



Yep, the Tec drives the stock Ariens headlight.
I'd never want to be without that as there are times I need to use this late at night.


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## Kiss4aFrog (Nov 3, 2013)

We'll you've answered your own question (finally ).

Since you already have a new carb your best bet is to go to the library and get a Tecumseh service manual or go on line and order one in if your library is a smaller one and then with manual in hand watch the videos and dive into adjusting those valves. 
Once that's done, see how it's running.

You have all summer to tinker on the Tec 

You might want to keep an eye out or search going on ebay for the Honda parts in case your pump dies and you choose not to replace it.
I have one looking for my higher output flywheel for the PS 1132 since it's only 18 Watt. Time is on my side and I'm not shelling out $135+ just for the flywheel.


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## RedOctobyr (Mar 2, 2014)

You can download the Tecumseh Technician's Manual for the L-head or (flathead) engines (692509) for free, here, as well as other sites: 

http://www.mymowerparts.com/pdf/Tec...P-4-CYCLE-L-HEAD-FLAT-HEAD-ENGINES-692509.pdf

Or search for "Tecumseh Technicians Manual 692509"

You can download a bunch of other manuals from that site as well. These are the Tecumseh manuals they have, which includes the OHV Technician's Manual: 
http://www.mymowerparts.com/pdf/Tecumseh-Service-and-Repair-Manuals/


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## CarlB (Jan 2, 2011)

my older 11hp harbor freight greyhound has a 12 volt electric start and charging system.


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## ChrisJ (Nov 27, 2014)

I was planning on pulling the engine apart this weekend weather permitting but now I'm confused.

A lot of people claim .008 for intake and .012 for exhaust.
Some claim .008 is min and .012 is max for both valves.
This other Tecumseh manual states yet another set of clearances.

What gives!?

And how warm should the engine be when this is checked. My dad says 30f is too cold and it should be done at around 70f if the manual states "cold".


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## classiccat (Mar 1, 2014)

ChrisJ said:


> I was planning on pulling the engine apart this weekend weather permitting but now I'm confused.
> 
> A lot of people claim .008 for intake and .012 for exhaust.
> Some claim .008 is min and .012 is max for both valves.
> ...


the engine should be cold when checked. Both exhaust & intake have the same clearance values. 

Good catch on 2 different values being recommended! Are both tables published by Tecumseh?


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## ChrisJ (Nov 27, 2014)

classiccat said:


> the engine should be cold when checked. Both exhaust & intake have the same clearance values.
> 
> Good catch on 2 different values being recommended! Are both tables published by Tecumseh?



Cold yes, but what is cold?

0f, 20f, 40f, 60f, 80f, 100f?


Yes, both of those are from Tecumseh.


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## ELaw (Feb 4, 2015)

ChrisJ said:


> Cold yes, but what is cold?
> 
> 0f, 20f, 40f, 60f, 80f, 100f?


Asks the guy with the world's coolest refrigerator... 

I'd say "room temperature" or about 60-80F.

Re the conflicting specs, I'd probably split the difference and shoot for 0.008" or so, maybe a little more like 9 or 10 thou on the exhaust.


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## CarlB (Jan 2, 2011)

Cold would just be room temperature as most people aren't expected to be working on an engine that is 20 degrees. As far as the lash is concerned the intake is normally about .002 less then the exhaust as the exhaust will grow more as the engine gets hot. The fuel and air passing over the intake valve tend to keep it much cooler than the exhaust. I usually go for .006 to ..008 on the intake and .008 to .012 on the exhaust


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## Dave C (Jan 26, 2015)

I dunno why there are so many conflicting specs. The Tecumseh manual for my HSSK50 said 004-008, so I set the exhaust midway at 006. The intake read .009 so I left it alone. The engine came up from 45 PSI to 90 but still didn't have real power. Then I read the Craftsman owner's manual and it said .010 for both valves. I opened it up to that and compression came up to 150 PSI and runs perfectly.


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## Grunt (Nov 11, 2013)

Hello Dave. Did you lap the valves when you adjusted the valve clearances? I have a hard time understanding how the compression increases when there was already clearance between the valves to begin with (on a cold engine). To little clearance usually shows itself after the engine is at operating temperature and the valve stems expand that allows blow by the unseated valves causing a decrease in power? Lapping the valves would have more effect than increasing clearances.


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## ChrisJ (Nov 27, 2014)

Dave C said:


> I dunno why there are so many conflicting specs. The Tecumseh manual for my HSSK50 said 004-008, so I set the exhaust midway at 006. The intake read .009 so I left it alone. The engine came up from 45 PSI to 90 but still didn't have real power. Then I read the Craftsman owner's manual and it said .010 for both valves. I opened it up to that and compression came up to 150 PSI and runs perfectly.





Grunt said:


> Hello Dave. Did you lap the valves when you adjusted the valve clearances? I have a hard time understanding how the compression increases when there was already clearance between the valves to begin with (on a cold engine). To little clearance usually shows itself after the engine is at operating temperature and the valve stems expand that allows blow by the unseated valves causing a decrease in power? Lapping the valves would have more effect than increasing clearances.



What about if those engines actually have a compression release setup and the extra clearance essentially disabled it?
My dads perfect running HMSK-100 tested around 50 psi and that's as high as it would go because of the compression release.


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## RedOctobyr (Mar 2, 2014)

ChrisJ said:


> What about if those engines actually have a compression release setup and the extra clearance essentially disabled it?


That was my thought as well. Admittedly, it's probably a little more than just that, if it also changed how the engine runs, not simply what a compression test shows. 

But if you set a ton of valve clearance, you will presumably "disable" a compression release. You'll also start reducing how far the valves actually open during operation, which will make it harder for the engine to breathe.


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## Grunt (Nov 11, 2013)

ChrisJ said:


> What about if those engines actually have a compression release setup and the extra clearance essentially disabled it?
> My dads perfect running HMSK-100 tested around 50 psi and that's as high as it would go because of the compression release.


That is my thought as well. Two much clearance will effectively eliminate the compression release and make it more difficult to start, even if it is "running" perfect.


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## ChrisJ (Nov 27, 2014)

Grunt said:


> That is my thought as well. Two much clearance will effectively eliminate the compression release and make it more difficult to start, even if it is "running" perfect.


The old style 8 HP Briggs and Stratton on my early 90s generator doesn't have one and it's a bear to start.

Of course, that BS engine still runs like the day it was made.

I have no doubt, my wife would never be able to start that generator but could start the snowblower with ease.


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## Dave C (Jan 26, 2015)

Grunt said:


> Hello Dave. Did you lap the valves when you adjusted the valve clearances? I have a hard time understanding how the compression increases when there was already clearance between the valves to begin with (on a cold engine). To little clearance usually shows itself after the engine is at operating temperature and the valve stems expand that allows blow by the unseated valves causing a decrease in power? Lapping the valves would have more effect than increasing clearances.


I lapped the valve first time around. Ground the stem for .008 lash, then lapped the valve and it dropped to .006. I figured that would be perfect, since it's in the middle of the 4-8 range in the Tec spec. I ran the machine and it still bogged under load. Filed a bit more off (ahem... crudely) and all is well.

My theory on this is that valve timing is a function of clearance.


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## ChrisJ (Nov 27, 2014)

Dave C said:


> I lapped the valve first time around. Ground the stem for .008 lash, then lapped the valve and it dropped to .006. I figured that would be perfect, since it's in the middle of the 4-8 range in the Tec spec. I ran the machine and it still bogged under load. Filed a bit more off (ahem... crudely) and all is well.
> 
> My theory on this is that valve timing is a function of clearance.



Why would valve timing have any effect on a low rpm compression test unless there was overlap?

I doubt the Tecumseh engines have much if any overlap. 

The only reason that gap is there is to ensure the valves close fully under all conditions. The best thing would be no gap if it was possible.


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## Dave C (Jan 26, 2015)

The tappet clearance and cam profile affect the amount of rotational time the valves are closed, which certainly would have an effect on compression. And I'm pretty sure that all 4 stroke engines have some amount of overlap, for efficiency.


Did you measure yours yet?


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## Kiss4aFrog (Nov 3, 2013)

Valve timing would have an effect on low RPM compression test as the shorter time the valve is open and less height it opens the less air that can get sucked into the cylinder and the resulting lower reading from not having the cylinder filled as much as it should.

Same with exhaust/intake overlap. It's designed in there for a reason. It allows the incoming fresh air fuel mix to push out the last of the exhaust gases as best it can.


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## ChrisJ (Nov 27, 2014)

Only thing I know right now is the HSSK50 appears to have a compression release built into it's cam. Also, the valve clearances on these engines should be .004 min .008 max so it sounds like even though you're at the extreme it is in spec.

That means you should have only seen low compression unless you were able to spin it fast enough to disable the compression release. According to everything I've found, the electric starter isn't even close.


Why by grinding it to the maximum spec all of a sudden the compression release stopped working I have no idea.


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## ChrisJ (Nov 27, 2014)

Kiss4aFrog said:


> Valve timing would have an effect on low RPM compression test as the shorter time the valve is open and less height it opens the less air that can get sucked into the cylinder and the resulting lower reading from not having the cylinder filled as much as it should.
> 
> Same with exhaust/intake overlap. It's designed in there for a reason. It allows the incoming fresh air fuel mix to push out the last of the exhaust gases as best it can.


I don't know,
Do you really think changing the clearance of a valve that is designed to allow enough air into the cylinder @ 3600 rpm is really going to matter at 50 rpm? I think you'd really have to take an awful lot off the stem to see an effect on a compression test.

I also doubt it would even start.


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## CarlB (Jan 2, 2011)

it is possible that before he took the head of to grind the valves the last time that the head wasn't torqued properly and the head gasket was leaking leading to the low compression numbers. Another thing could have been if the throttle not opened during some of the tests.


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## Dave C (Jan 26, 2015)

ChrisJ said:


> I don't know,
> Do you really think changing the clearance of a valve that is designed to allow enough air into the cylinder @ 3600 rpm is really going to matter at 50 rpm? I think you'd really have to take an awful lot off the stem to see an effect on a compression test.
> 
> I also doubt it would even start.


I dunno what to tell ya, other than by personal experience on my own machines. I can say that compression increased and power under load was drastically improved.

Valve clearance matters.

If you're doubting the results of a compression test, then do a leakdown test instead. If you hear air hissing through the muffler, you need to set exhaust valve lash.


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## ChrisJ (Nov 27, 2014)

Dave C said:


> I dunno what to tell ya, other than by personal experience on my own machines. I can say that compression increased and power under load was drastically improved.
> 
> Valve clearance matters.
> 
> If you're doubting the results of a compression test, then do a leakdown test instead. If you hear air hissing through the muffler, you need to set exhaust valve lash.


Dave,

Please understand I am by no means calling you a liar.

Other than I don't understand the results, I don't know what to think. I just wanted to make that clear to you, and anyone that reads this thread.

I am not doubting what you are saying.


Regarding a leakdown test, if I had the tools I would, but I don't. But I think it would be silly to spend the money to buy what I need to do the test when I can just pull some things off and check the valve clearance. The only reason I haven't done it yet is mainly due to getting a bad cold and have been trying to recover all week, but also partially because it's still been pretty chilly out.


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