I just removed the head and everything is covered in gunk and caked on graphite-like substance. Any suggestions on how to clean it up? chemicals, dremel attachment, technique?
thanks!
Do a Google search for "how to clean carbon deposits from pistons".
Oddly enough, Permatex gasket remover popped up with good results......
Quote from: sashkar2000 on July 28, 2013, 09:45:21 PM
I just removed the head and everything is covered in gunk and caked on graphite-like substance. Any suggestions on how to clean it up? chemicals, dremel attachment, technique?
thanks!
Put pics up before you clean it. You could be washing away the evidence of what was the problem.
Cool.
Budhda.
hi Budha. i got some pics in the 'Engine won't start after spraying carb cleaner' topic. I sprayed a lot of crap in there which caused a backfire and bent my valves and hopefully didn't damage anything else.
a Back fire will NOT bend valves, you said you were turning the wheel with it in gear..........you had to have turned the engine backwards more then a few degrees (doesnt take alot) there is no way you will bend ONLY the intake valves on a engine that was not running at the time. if it happen while it was running you would have a fair amount of damage to top of piston. Not to mention you would likely bend atleast one exhaust valve too. but from the pictures thats not the case.
when the engine is running, its spining forward, the exhaust valves are opening as pistons come up and start clossing just before TDC to clear the pistons. the intakes open as the piston travels away for the intake stroke. if you reverse the engine direction the intakes are opening as the pistons come up. added slack in timing chain from reversed direction opens the intakes alittle late in the stroke hence ONLY the intake valves were bent.
Hmm, interesting explanation. I'd like to agree and confirm it, but I really doubt I moved the in gear wheel the wrong way. It was really hard moving it, so it wouldn't roll backwards unless I applied a lot of force and I only pulled up on it.
Are you quite certain there is no other damage? I don't think I posted enough pics to determine that.
I poured 1.5 cans of carb cleaner that ended up on the intake valves. Could that have weakened them when that crap burned? Actually at this point there was still compression I could feel with the finger test. Thinking the valve seat was dirty, I sprayed seafoam (i got it in gas form) waited 5 minutes and cranked. This caused another huge explosion which killed compression.
The exhaust valves weren't dirty but their clearance was minimal, about .03mm and it was hard removing the buckets, they barely turned.
I'll take more pics over the weekend and ask the machinist to inspect the head.
if you used that much carb cleaner, change your oil and filter too. i will lay money on a fair amount of that ran past the rings and is in the oil. pull the jugs off and grab a piston and see how much slack it has, there should be a small amount side to side along the crank pin and same for piston on the piston pin. but up and down (with crank not rotating) and forward and back should have nearly nothing just pivoting motions if you dont feel any, you should be ok. just remember to reassemble everything with lube and crank the engine over with fresh oil and spark plugs removed to prime the oil system before you attempt to run the engine.
Will def check that. thanks for the heads up.
Is it enough to coat parts with motor oil for reassembly or is a differnet lube needed? Also when i removed the cam journals some whitish oil sprayed out. Any idea what that was and how to replace?
Certain parts call for grease, others are fine with a light coat of oil - check the service manual for specifics.
Whitish oil? Only thing I can think of would be condensation in your motor oil, causing it to become "milky".
yup and yup. using a good grade oil and just coating stuff is good enough for reassembly but like i said, once together and your sure everything is timed correctly, make sure the spark plugs are out and oil is full, and use the starter to spin the engine allowing the oil pump to prime the oil system