Head gasket?

slomo

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poulan pro riding mower cut out while mowing. Would not restart. Made loud popping noise when turning over.
checked compress in both cylinders. 30lbs in left and plug covered in wet oil. 120lbs in right cylinder, plug normal.
suspect head gasket, our local repair shop on vacation this week
Local repair shop on vacation in peak mowing season? You must live in Colorado or Canada. Around here, you can't even pull into the parking lot to get a mower looked at. Our mower shops are busy.
 

slomo

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All four valves were set to .005 when the pushrods were recently replaced. Upon rechecking all four are still at .005.
thx
There are two top dead center conditions on a four stroke engine. You could of set the valves on the wrong stroke.
 

slomo

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I can't recall exactly why the recommendation is to move the piston 1/4" past TDC,
I use the OVOOVC method with no comebacks or trouble.
One Valve Open, One Valve Closed, adjust the valve that is closed.
That 1/4" deal is to get past the compression relief.
 

slomo

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While this can be operator error like running then engine at lower speeds than WFO or failing to clean the cooling fins
Agree on this. OP is trying to fix the problem overlooking what might of caused it to begin with. Need conformation on are the cooling fins and block CLEAN. As in a shiny new engine look down to bare aluminum. Pictures of everything assist us in helping you.

Agree with sgkent. Take the battery to an auto parts shop. Have the battery load tested for free.

Agree with Scrubcadet10. Need to do voltage drop testing on the entire + and - sides of the battery, while CRANKING engine. Also make sure the ground strap is a stellar fella'. Check every cable and connection on the + and - sides. Polish every connection while you are there. Little dielectric grease is your friend here. Star grounding washers should be added.

Do you power wash this after mowing? If so that is another topic as what not to do.
 

Kparent

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Reset the lash to .006 using ovoovc method.
The engine now starts repeatedly without hesitation!
There were mice nests and caked on debris under the cover when these problems began. I cleaned it out then but I cleaned it all again more thoroughly getting between all the vanes with a plastic brush. I’ll add engine inspection and cleaning to my regular maintenance routine.
many thanks to all for your contributions in helping solve these issues!
 

slomo

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Reset the lash to .006 using ovoovc method.
The engine now starts repeatedly without hesitation!
There were mice nests and caked on debris under the cover when these problems began. I cleaned it out then but I cleaned it all again more thoroughly getting between all the vanes with a plastic brush. I’ll add engine inspection and cleaning to my regular maintenance routine.
many thanks to all for your contributions in helping solve these issues!
Cleaning the cooling fins and block is a yearly to-do engine maintenance item in ALL mower engine manuals.

Dirty cooling fins is what caused this to happen. Keep the fins clean and the oil on the full mark. Easy right?
 
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