thrust bearing FTW!

 

i say bent crankshaft. the mains...probably 2 of them will be pounded, not spun.

 

so... any new news?

 

OK, today the engine is out and disassembled. Let me give some history of this engine for those of you that don't subscribe to my fan magazine. I upsized and upgraded everything two years ago, and from the first revolution it has had what I regarded as an extremely noisy valve train. I don't put many miles on it, but I think waiting two years for the lifters to pump up is too long. The damage we found today was two camshaft lobes had gouges in them the shape of the lifter's rollers, and one of those lifters had a roller that was damaged. The gouges were probably 1/16" and 3/32" deep. The rest of the lifters looked good, but maybe six or so more of the cam lobes had the nose wiped off. It had to be a bad heat treat.
So apparently all of this diamond dust that used to be hardened-steel cam lobes circulated through the motor, and took out two main bearings. They did not spin, and for some reason the crank looks undamaged, we'll mike it tomorrow.
I am looking forward to having a quiet engine soon.
I can't decide on the contest. Even though main bearings is the answer, the damage isn't from what you would think. Then again, it is the answer to my question. Hmmm , let me think about it.
Pictures soon.

 

 

I declare the winner. As the first to say main bearing, he wins, because nobody guessed that it was the #1 and #2 mains. They must be first in line out of the oil pump (?) and got the most abrasive.
CHEVRACER83, since I still can't come up with a prize, you name it, anything you want.

 

Two posts up

 

What Brand of cam Was that?

 

I'm going to wait and see if there's any chance of warranty before I start badmouthing them. It shouldn't be long until I get an answer.

 

I understand. My intent was not to bad mouth any one company but to try and shine some more light on the cam portion of it.

As far as The cam goes the Blanks them selfs are usually only heat treated after the initial raw blank is produced. The cams main journals are the only thing that is finished on the blank. The cam grinder must finish the lobes. Most of the new cams out there are not heat treated unless its a billet roller or if its specifically requested for your application. Most cam grinders are going to blame the cams failure on poor oiling or inproper preload. No one is going to spend the time to send it out and see if the cam was at fault. These things are made in large batches so it is possible to get a soft one here and there. I can't speak on be half of the cam Blank producers but I am sure they only pull something like 2-3 cams out of a batch at random and check them for over all quality.

I wish you luck and hope they will stand behind there product and atleast grind you another cam.