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Discussion Starter #61 (Edited)
OK....most obvious...no blown head gasket...the 3rd, 4th and 5th pictures show the inside of your cylinder and the position of the piston in it...if you notice in picture 4 is where you can see it best...the piston is off center...in my opinion, you need to bring it to a machine shop and have them use a device to measure if that is excessive wear...can't really see enough of cylinder wall to see if it is scraped up.....but it looks like you need new rings at a minimum and possibly need to bore out the cylinder if it is not past tolerances...if you got this apart this far and are confident you can get it back together...you should be able to do the rest of the job other than boring out the cylinder
So I need to take the piston out and take it to a machine shop so they can see the exact specs on it? Or do I need to take the whole thing cylinder included?

The valves are very snug, should I mess with them or just clean them up? Or to really find out do I need to go ahead and pull those?
Quick question, which might be stupid, to get the piston out do I go flywheel down to do that? Thank you guys for the help.
 

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i wouldn't waste my time trying rebuild that motor,i have never seen a gap like that,i think you would be better off trying to find another motor
 

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I think we all need to inform people there is a difference between "won't crank over" and "won't start".............

"won't crank over" is a starter/battery/wiring/hydro lock, problem.

"Won't start" is a fuel delivery, wiring, spark plug, points, valve, timing problem.

Not to be a butthead BUT for "we" that may be able to help you "we" need proper terminology to assess the situation. :tango_face_devil:
 

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I did a compression check with my finger, and it wasn’t giving me enough to push my finger away. It was actually sucking my finger in and not pushing it off. Took it to a buddy and he said it’s lost pretty much all compression. He said that means the engine is pretty much shot. If I’ve lost compression is there anything I can do?
Not true. Anytime an engine fires up and runs for 2-3 seconds that tells you it is mechanically capable of running and you usually have a fuel delivery issue.

When you have a plug hole sucking your finger in, you have a stuck or sticking intake valve. The plug hole should puff puff puff puff puff your finger off and not suck it in.

Always put new or known good other plug in and use starting fluid to test or some gas into carb intake. Squirt some oil or chain lube into the plug hole 93-4 squirts from pump can or 1 oz and turn over by hand with plug out then put plug in and try to start with starting fluid. This raises comp if rings worn by sealing them better.
 

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Brain fade... The CV series in this hp range have a compression release. Given we are close to 70 posts, I have no idea if it has been mentioned. I may have mentioned it.
The CR will bump a valve and lower the torque needed to crank the engine when starting. A flyweight will overcome the spring, and allow normal valve operation when rpms increase.
I have no idea of the clearance mentioned by one poster. To me, the piston fit into the cylinder looks normal. The valve coloration from deposits looks normal. There's no excessive carbon deposit. No deposit indicates 1)no oil being leaked from the crankcase, 2)no bad valve guide oil leakage, 3)decent carburetion and 4)decent compression or it wouldn't run.
Because of all that, I think this is just being messed up by something missed. It could be that the valves have worn or the seat has worn, such that the lifter won't let the valve seat properly. A test is to collapse the lifter(apply pressure to the pushrod side of the rocker arm until the lifter lets the oil out. It will take time under full push), and check that there's clearance with the lifter on the heel of the cam. If there's clearance, the valve should work, IF the seat and valve seating area are good.
You can test the latter by placing the head upright/downright? so it will form a dish. Fill said dish with gasoline/kerosene/water and see if it leaks out the valves. If it does, the valves need attention. If not, they should work. Being as it is apart this far, as usual for me, I suggest cleaning up the valves and seats using lapping compound. Clean thoroughly if you lap the valves or the compound will eat the engine from the inside out.
Put back together. Install 1/2tsp of fuel into the carburetor, inside the air cleaner area, under the triangular metal lid, and crank the engine.
Post the result.
tom
 

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Discussion Starter #67
There they are cleaned up. I formed the dish and nothing leaked out. You do mean to do the test with the cam taken off the mower correct? Nothing came out. Should I put it back together and see what we got or is there anymore test you can think of?
 

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Discussion Starter #71
Well after it sitting apart for 5 months and being confused as **** MR DIY is taking this bad boy to the shop. I’ll let y’all know what they say
 
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