Hey everyone, long story short, cam only ZO6 with bolt-ons etc..I began getting the camshaft malfunction code so I replaced it only to find that it didnt cure the situation.

I then made the dreaded decision to remove the steering/front cover etc...Only to find that the cam sprocket was loose, so I removed it lock-tited the retainer plate/torqued it, then the sprocket and reassembled the engine nice and smooth. I start the car only to find that the code is gone but the car has developed a squeaky noise somewhat similiar to a belt but coming from somewhere in the engine. I removed both belts to see if it was a pulley/idler, but no luck.

So today I decide to disassemble once again to fix the problem which I thought would be coming from the front cover area, checked everything once again and retorqued/reassembled. Unfortunatley I had a problem with the pulley this time...it pulled in perfect as previous, but the bolts seemed to stick on my removal of install bolt. It seems to have stripped the last half inch of on the tip of the TTY GM bolt. I believe there "may" be some thread damage to the crank , but I'm going to try and chase/tap the thread to see if I can rethread the new bolt. I did start the car(quick install of the tb/airbridge)only to find the noise still apparent!

What could the noise be, and what is everyone's advice? I did have some 2nd party advice form a reputable Corvette shop tech, but he is stumped as well.

What is everone's thoughts on the crank thread situation?

My main reason for posting this is I figured someone may have experienced one or both of these problems in the past and could offer some insight.

Sorry for rambling and thanks in advance for the thoughts/direction.

Alan

 

The noise is similiar to a belt yet not as high pitch and slightly more metallic sounding.....almost like a freezing/frozen bearing.

Possible oil pump(still have great oil pressure and only 28k on the car), or possibly even a lifter out of wack due to slight possible cam movement?

TIA!

 

Hmmm, since the cam sproket came loose Im thinking lifter or cam bearing chewed up....The cam CAN move slightly wihout the chain holding it....maybe it caused a bearing to get scarred or a lifter to get screwed up? Id pull the cam, but be sure to use two wooden dowels to hold up the lifters. The inspect the cam for wear and the cam bearings... To pull up the crank pully I have found its best to use either a crank bolt that has only been used once, or the best, threaded rod and nut.

Good Luck!

PS I hate pulling that ******* steering gear, but even worse is the power steering pump assembly! I had to do mine twice as well, when I pinched the oil tube O-ring the first time.

 

The car was running quiet with the code prior to the R&R, but as soon as I tightened everything up it was not throwing the but had this nasty sound....

As far as the power steering is concerned I didn't pull that either time just to remove the front cover....

Thanks for the insight, I was thinking that a lifter had gotten twisted misaligned with the cam lobe....

 

Yeah, I would lean towards a lifter(s) also....but odds are if the lifter got chewed up so did the cam lobe(s).