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My WR burns oil if I run it at max revs. While running, I removed the oil dipstick and it puffed up from crankcase pressure. Removed the stick and it blew air and oil up out of the tube. This is an L head style engine. My question is are my rings not sealing like normal? The vent to carb tube had a lower level of air going to the carb to reburn. Must be some baffeling inside to slow the air velocity down before it hits the carb. It is doing just like a Briggs Intek engine with the classic blown head gasket. What do you guys think I need to do? If I run it at a medium rev, it doesn't burn as much oil. I top if off at the full mark. I get one mow out of it on max revs. Next mow I need to add just a bit of oil to bring it back to full. It drops to mid normal oil level range every time. What do you guys think?

slomo

My guess is bad rings. Time for a leak down test or at least compression test.

Compression was a thought. From the rope it feels ok. Time to put a gauge on it. My thought was sticking rings. Got this Snapper from a co-worker. No telling how long the mower was sitting in his shed. I sprayed WD-40 into the cylinder. Hoping the solvent would loosen the rings over night. That seemed to slow the oil burn down a little I think. I would love to open her up but no gaskets are available anymore. Unless you guys know where some are to be had?

slomo

Can’t help with gaskets unless you provide us with engine numbers.

Compression cold was 60psi. Removed the head. Did a carbon combustion chamber removal. Bore is perfect still. Zero scratches of any kind. Noticed the piston rings push a small amount of oil toward the head when you rotate by hand. Rotating by hand, there is no sound of the rings doing their job. No slight dragging sound and very easy to rotate with one finger. Looks like rings are dead. Probably have to remove the piston to unstick the rings if they are still good. Valve guides had some slop. Could use some new ones after 4 decades of service. Probably no sense squirting oil into the chamber to improve compression. Rings seem to have plenty of oil in a bad way. Would like to run some Rislone and see if the rings would loosen up. Nothing to lose now I guess.

slomo

Engine numbers??

Since you have the head off. Turn engine with. Cylinder up and piston down in bore and pour a couple ounces of Seafoam in and let it set a day. Rotate the engine a couple times and repeat the seafoam treatment. Change the oil put head back on and see how it runs and check oil consumption. Adding a few ounces of seafoam to the oil will clean the crankcase.

Hammermechanicman said:

Since you have the head off. Turn engine with. Cylinder up and piston down in bore and pour a couple ounces of Seafoam in and let it set a day. Rotate the engine a couple times and repeat the seafoam treatment. Change the oil put head back on and see how it runs and check oil consumption. Adding a few ounces of seafoam to the oil will clean the crankcase.

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I did a similar thing last night with WD-40. WD is a pretty good solvent. Need to dump the oil and fuel. Put the cylinder up vertical and douse with WD-40. Surely with leaking rings, any solvent will cover the rings and hopefully loosen them up. Right now there is no audible ring drag in the bore. No friction either as stated before.

slomo

Hammermechanicman said:

Since you have the head off. Turn engine with. Cylinder up and piston down in bore and pour a couple ounces of Seafoam in and let it set a day. Rotate the engine a couple times and repeat the seafoam treatment. Change the oil put head back on and see how it runs and check oil consumption. Adding a few ounces of seafoam to the oil will clean the crankcase.

Click to expand...

I would like to crack it open and remove the rings. Don't have any replacement gaskets. My luck it would leak oil all over if I did that.

I would think this has a cast iron liner in it. I didn't notice one. I will look again, still cleaning carbon and such. Anyone know if these Japanese engines have a cast iron bore?

slomo

Use a magnet to check the bore.

Hammermechanicman said:

Use a magnet to check the bore.

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Copy that. Should be an easy check. Thanks for a good way to confirm it.

slomo

Gaskets are available for your engine, which crosses to a Robin EY20.

Rivets said:

Gaskets are available for your engine, which crosses to a Robin EY20.

https://www.subarupower.com/media/manuals/128898075482130000.pdf

https://subarupower.com/media/manuals/128897426824197420.pdf

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Thanks Rivets.

I have these engine numbers. You probably need more numbers?
Wisconsin Robin
Model WI-185V
Spec No 800454
EY-20

slomo

Service manual pdf says 6.3:1 compression ratio. Wonder if my 60psi would equate to that? Sounds plausible.

Pdf file says cast iron bore. Thought it was.

Forged high carbon steel crank and forged rod. No wonder these were such sought after engines.

slomo

slomo said:

Service manual pdf says 6.3:1 compression ratio. Wonder if my 60psi would equate to that? Sounds plausible.

Pdf file says cast iron bore. Thought it was.

slomo

Click to expand...

6.3 x 14 = 88.2 PSI so it is a little low

bertsmobile1 said:

6.3 x 14 = 88.2 PSI so it is a little low

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Right, I would like to see 80+ if possible.

slomo

Rivets said:

Gaskets are available for your engine, which crosses to a Robin EY20.

https://www.subarupower.com/media/manuals/128898075482130000.pdf

https://subarupower.com/media/manuals/128897426824197420.pdf

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Pdfs seem to cover horizontal shaft engines.

slomo

slomo said:

Right, I would like to see 80+ if possible.

slomo

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If you open up the valve clearance sufficient to defeat any ACR built into the engine.

When you remove the oil dipstick the oil slinger will spray oil and air out the tube. (assuming a splash lube motor) Compression is probably ok. What oil are you using the engine?

slomo said:

Anyone know if these Japanese engines have a cast iron bore?

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Yes, it is iron sleeve.
Sounds like the bottom ring is not wiping the oil off the cyl wall or perhaps the drain holes from that ring are all clogged.
If I were u, i would remove the piston and clean the piston and replace the rings. I mean it is 30ish years old....
While you are at it, rent the cylinder bore gauge from Autozone or the like and measure it while it is open to see if the cyl is out of round.
Gasket wise, i used silicone gasket when i opened mine up, and you can always make a gasket for the cylinder head if yours falls apart.

tom3 said:

When you remove the oil dipstick the oil slinger will spray oil and air out the tube. (assuming a splash lube motor) Compression is probably ok. What oil are you using the engine?

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I've never opened the oil stick when running till I did this one. I've seen engines like the Intek's, that is one trick to find a blown head gasket. I'm running Wallys World Supertech 30w in all my mowers. This is a splasher engine.

slomo

One thing I've seen that is weird. The cooling fins of the motor get jammed up with grass etc and the motor starts running hot. Cylinder distorts at the head bolts. If it runs for a while like that you'll see a wear pattern showing right beside the bolt holes on the cylinder walls. Might be hard to see but worth a look.

upupandaway said:

Yes, it is iron sleeve.
Sounds like the bottom ring is not wiping the oil off the cyl wall or perhaps the drain holes from that ring are all clogged.
If I were u, i would remove the piston and clean the piston and replace the rings. I mean it is 30ish years old....
While you are at it, rent the cylinder bore gauge from Autozone or the like and measure it while it is open to see if the cyl is out of round.
Gasket wise, i used silicone gasket when i opened mine up, and you can always make a gasket for the cylinder head if yours falls apart.

Click to expand...

Yup, bottom ring is slacking on the job. Head gasket came off in one piece undamaged. It was a metallic shim looking gasket. Guess this winter I will open her up and do some ring and piston groove cleaning. Hoping the rings are simply stuck with carbon and cleaning will restore them. Bore is pristine. Like you said, drain holes in the piston are probably clogged.

slomo

tom3 said:

One thing I've seen that is weird. The cooling fins of the motor get jammed up with grass etc and the motor starts running hot. Cylinder distorts at the head bolts. If it runs for a while like that you'll see a wear pattern showing right beside the bolt holes on the cylinder walls. Might be hard to see but worth a look.

Click to expand...

Cooling fins now, are clean. Can't attest to the 4 decades of previous usage. I will do another bore inspection this winter.

slomo

One thing to add is this engine sounds like it has a rod knock. That or the muffler has gone in super performance mode?? Wondering with the head off, can I slowly rotate the engine and watch piston movement to see if there is a rod issue? Like flywheel turns but piston doesn't say in a 1 degree movement then piston moves as normal? Might not be able to see something in the thousands of an inch of excess slop with the naked eye. Obviously better to measure the little guy.

slomo

slomo said:

One thing to add is this engine sounds like it has a rod knock.

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R u sure it is rod knock u hear? You can find out if it is piston slap you hear while u have it open, push right and left side and look if the piston rocks when u do it. If slap is from the crank journal, i guess you could gently turn the crank a hair back and forth while the piston is at middle position to see if there is play\clicking before u open up the block...

upupandaway said:

R u sure it is rod knock u hear? You can find out if it is piston slap you hear while u have it open, push right and left side and look if the piston rocks when u do it. If slap is from the crank journal, i guess you could gently turn the crank a hair back and forth while the piston is at middle position to see if there is play\clicking before u open up the block...

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I can move the piston side to side in the bore with my finger. Guessing this is a forged piston normally running a wider bore gap?? Or it's 40 years old and worn. I can see what looks like the piston doesn't sit proper in the bore center maybe??

Think the rod is okay. Seems to be directly attached to the piston meaning I can't "see" any movement other than the piston going up and down as normal.

Found a block of grass/dirt on the very bottom of the cooling fins. There is a metal air directing plate/shroud that goes around the block. Blob was stuck in there where I couldn't see it. Maybe 1.5" wide x 1". All clear and open now.

There is a tiny hole in the center of the piston. Doesn't seem to go all the way through. I can insert a small screwdriver tip in it.

slomo

I've got the engine bore near vertical now. Sprayed WD-40 (solvent) a couple times. Carb cleaner, this garage door lube that says it removes stuck items, Diesel and now ATF. Will keep soaking the rings in effort to loosen them up. Most likely they will need to be removed from the piston and cleaned up.

Noticed with this soaking the fluid gets by the rings now. Does take a few minutes to lower the level in the bore. Depends on how thick the solvent was. Maybe a week or more worth of soaking will help?

slomo

Thinking about heating the outer piston face circumference to loosen the rings. Fill the cylinder back up with solvents. Donnyboy heated the rings directly.

slomo

Usually with a sleeved bore the piston is cast aluminum with no coating or treatment. Sounds like lots of standard wear in that motor. And the trend has been to use short skirt pistons in later years which leads to piston slap pretty early in the motor's life.

Best thing i have ever found to decarbon and unstick rings is Seafoam.

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