whats this noise

engine starts at first crank, runs great, doesnt get hot ,but has major blowby. So whats this noise, it doesnt do it all the time. Thanks.


http://www.youtube.com/watch?v=x-Nhgp72nHM

 

So many possibilities, but I think it is going to come apart to really know. Not what you want to hear probably, but that doesn't sound too good. Kinda sounds like Christine when she was limping back from frying those hoodlums.

Don

 

Exhaust leak. Maybe your spark is a little slow.
You need to speed your idle up by the way.

 

Hi chainsaw,, if i were to guess i would say loose converter bolts or connecting rod knock Good Luck jim

 

Check the dust cover on the transmission for marks from the flexplate.

 

I had an engine with a sound similar to that.......Turned out to be the thrust surface on the main bearing was wiped out letting the crank walk back and forth. The noise went away off idle. Hard to tell from the video

 

Converter bolts was my first guess too. If not in that area its gonna be something ugly inside the engine. Didn't lose a carb base plate screw down the intake did you?

 

Sounds like a bad valve??? Maybe....Idunno.

 

Converter bolts are hitting the TH350 cover.......but if you've got "major" blow-by, you have bigger issues....

 

It sounds exactly like that...lol !


Get your big long screwdriver and start using it around the engine to listen through to find out just where it's coming from.

 

what noise? i couldn't hear it over whoever was banging on a garbage pail with a stick.
it does sound like the flywheel cover is hitting.

 

One bolt in the flex plate too long?

 

Loose or too long converter bolt, had it happen on an OT truck.

 

The dust cover is sitting on the shelf, Ill check the bolts tomorrow anyway to see if their loose. Could a bad header leak cause that sound ? The flanges are ground flat from bottoming out, I havent checked the gaskets yet. Oh damn, now I have to watch Christine again

 

I'm going to say bearings. You didn't mention your oil pressure? I've heard a similar sound and when we pulled it we found a stacked bearing and the piston smacking the head. By quieting down off idle, I'd just say a wiped bearing and when the oil pressure builds there is enough pressure to quiet it down.

Go for the easy things first though and look for bolts, etc. mentioned above.

 

Pressure is good, 45 to 50 cold and around 25 to 35 when warmed up. Im sure it needs a rebuild but i was hopeing to get another year out of it. Probably wishful thinking