Snowblower Forum banner
1 - 15 of 15 Posts

·
Registered
Joined
·
7 Posts
Discussion Starter · #1 ·
So my old JD snowblower supposedly blew last winter, but ive taken the motor apart and the connecting rod, cam and valves all seem to be okay. The engine was seized but i put a pipe wrench on the flywheel and managed to free it up a bit.

But the engine is still hard to turn over,i can turn by hand on the flywheel but i have to use quite a bit of force. Cylinder and piston seem okay? Had the sump cover off and took the cam out and still no difference.

Could it just be because theres no oil in at the moment as i have the sump cover off? Loaded everything in the crank case and piston head with pb blaster, think that might be what freed it up a bit but still not turning freely and smoothly.

any ideas?
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #3 ·
Water was contaminating the oil, think it might have overevved all of a sudden gray foamy oil started pouring out of the breather, stopped it and it sat overnight then the next morning it was seized.

Everything seems to be moving smoothly just hard to turn, could be crank bearing? Would make sense. I dont think it would be the piston rings as the piston is moving up and down.
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #4 ·
Engine was moving after it happened. Then i drained the oil, left it over night then it was seized
 

·
Super Moderator
Joined
·
1,632 Posts
I'd get the spark plug out and fill the cylinder with MMO or likewise and let it set... work the engine little by little as the MMO drains into the crankcase, then clean that out good and fill with fresh oil. Cross your fingers and hope for the best.
 

·
Registered
Joined
·
2,939 Posts
if the engine is stiff to turn over it is likely the connecting rod bearing. i freed up a engine like that and got it running but there was definitely a rod knock. it is likely cheaper to replace the engine than to fix it. if it was just a stuck piston they usually spin pretty freely from the moment you break them free but the ones with a bad bearing are very slow to free up and are usually a ticking time bomb even if you do get them running.
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #7 ·
This has kinda become a mission for me haha. Yeah connecting rod bearing would make sense. I actually just picked up another 10hp the other day but turns out the crankshaft is an 8th of an inch bigger and doesnt line up with the pulleys of course.
 

·
Super Moderator
Joined
·
1,632 Posts
Well that's the thing... the engine might be toast, might not be. 50/50, 60/40... anyhow you don't have much to lose by trying. If it runs and you get bad noises you can stop and re-evaluate... maybe... 🤣

You didn't mention any irregularities found when you did the teardown so you just might get away with it. 🤞
 

·
Registered
Joined
·
1,765 Posts
I have an old 826 where it was extremely difficult to turn over. Ended up being valves needing to be lashed. The shop did a great job with it and it is 10 times easier to pull start.
 

·
Registered
Joined
·
2,939 Posts
I have an old 826 where it was extremely difficult to turn over. Ended up being valves needing to be lashed. The shop did a great job with it and it is 10 times easier to pull start.
that doesn't sound like it should cause a engine to be difficult to pull over. i would guess the shop told you that because they probably didn't want to explain what was really wrong and valve clearance is simple to blame even tho on most machines the valve clearance usually gets smaller with age which should make it easier to pull over especially when it get to the point where you have no valve clearance and the exhaust valve is not sealing.
 

·
Registered
Joined
·
29 Posts
Then was oil foaming out of the breather because of water boiling in the oil?
 

·
Registered
Joined
·
3,959 Posts
Water in the oil will turn it light brown and foam in many circumstances .....

drain that oil and put in Full Synthetic 5W30
 

·
Registered
Joined
·
658 Posts
Show us a photo what the connecting bearing end looks like. I suspect you have a rod seizure. I say this because you say it was still turning over when it was hot but locked tight when it cooled. You must also look to see it the rod shows any sign of being bent.
 
  • Like
Reactions: nitehawk55
1 - 15 of 15 Posts
Top