I only have less than 500 miles on my new motor and it sounds like I got bad bearings already. The last time I drove it I had NO problems, and no sounds. Today I started it and I hear a very loud knocking sound coming from the motor that gets faster as the revs go up. I'll have a video up in a few minutes I hope. How can something like this happen over night???

 

Here is the video...damn i'm so depressed right now. Sorry, photobucket was the quickest place I could think of to upload it.

http://s6.photobucket.com/albums/y22...t=100_1286.flv

 

personaly dont sound like bearings... set your valve lash again.. engine warmed up and cooled down...

 

To begin with, bearings can go out with no warning on brand new motor. Having said this about that---I agree, that it doesn't sound like a bearing to me.

Number one Do not run the engine if you have no oil pressure----period.

Check for location of the noise---i.e, immediately listen to the valve covers and header flanges to determine if it is in the valve train or a leaky exhaust.

Good luck.JMHO

 

check your flywheel bolts

 

I am thinking header collector leak, check it out.

I once had a similar noise that came out of nowhere and I panicked. Turned out the collector bolts backed out and caused huge exhaust leak.

 

oil pressure isn't an issue...at least the stock(I know crappy) gauge has read pretty normal pressure for the most part. Can the exhast really make that much of a sound...its pretty stinkin loud. What would a failed lifter sound like? I'll mention that I am using comp-r lifters

 

Doesn't sound like a bearing to me either. I would check the valvletrain. Collapsed lifter that's just bouncing around in there?

 

I'm hoping valvetrain. like a lifter collapsed or something. damn...I was just about to re-adjust those things to make sure they weren't too tight this weekend... Hopefully i'll get a chance to take the valve covers off this weekend and see. It just seems way too loud to be that though, but i've been wrong before....many times lol

 

Something is hitting something.
Kinda sounds like the crank or flywheel hitting something.
It could be exhaust but don't think so. It also sounds like there is another lighter tapping in there too.
Did ya bend the pan?
Anything inside the pan that could have come loose and hitting the crank? Baffle maybe?
Take your belt off and try it although I don't think that's it.
Get under it and see if ya can pinpoint the noise.
Any chance a rod bolt is loose hitting the cyl or pan?
Pan bent from hitting PS rack?

 

I agree with LR - does not sound like a bearing problem...check your converter bolts along with anything else external that could be hitting.

Not an exhaust leak and not valvetrain.

$100 on some bolt hitting something or baffle...sounds external though....my bet is on converter bolts

 

Well here is the same sound from up top. Don't know if this will help anyone. This is why CZ28.com is great...because of people like all of you helping others out. Thanks!


http://s6.photobucket.com/albums/y22...t=100_1287.flv

 

Sounds upper end to me like... rocker hitting valve cover. or rocker tapping on spring (too much lash), Those are easier to check lol, being as I've only had manuals I can't contest to the sound of lose converter bolts, but most of the time these guys are pretty close. EDIT: I've heard of people using the stethoscopes(sp?) and puting them up to the valve cover to determine which one it is..

 

I would think that if it was the crank or rods hitting the windage tray or something that it would have done that from the start. Maybe it it a bolt or something that has backed out like Machinist One said.

 

That sounds like something loose/bent/broken in the train. Take the covers off and see.
Don't run it any more than ya have too before ya find the problem. It just don't sound like a loose rocker.

Lifters don't just collapse by them selves for no reason.
Is it missing?