Today I noticed my rockers making alot more noise than normal, so I pulled the valvecover off to make sure the lash was still correct. When I did, I found that the number 1 cylinder's exhaust valve pushrod actually wore a groove into the guideplate towards the front and the rocker was half off the valve tip. The rocker seems to have alot more resistance to going back where it's supposed to be, it seems to want to stay where it wore down the guideplate. I'm wondering if anyone had these problems? The pushrod doesn't appear to be worn down at all, they're stock '94 pushrods pushing 1.6 comp promags and comp 987 springs on a 224/230. Lifters are comp high energy. I'll take pics soon...

 

I can't figure out how to post pics. But either way, I'm going to order another set today...anybody have any idea how this can happen or be prevented? I took every precaution I could think of...checked for bent pushrods...even applied assembly lube when I put it together!

 

Sounds like a bent and/or flexing pushrod.

 

That's what I thought. However when I pulled it off and inspected them they did not appear to be bent...not even worn thin, just normal wear marks from the guideplates!

...as far as the flexing part goes, can stock pushrods flex? I wouldn't think it would happen but the motor has seen 6k rpm a few times...6000 is my shift point. With Comp 987 springs I wouldn't think that would be a problem, is there something I'm missing here?

 

Take that pushrod back out and roll it on a piece of glass. It's pretty easy to see if ones bent that way, and it doesn't take much to screw things up when using guideplates. I'll betcha it's bent.

Dave C.

 

OK...I'll give it a try. I tried a visual inspection and a roll test but that one's worth trying too. I'm kinda hoping that is the problem so I can fix it!

 

Someone else was complaining the other day about their GM guideplates being off a little. It was only on one cylinder like you are saying. I'm not sure how it all worked out though, if it was the guideplate or something else. You might be able to search on it. It's been within the last few days.

All I know is that I'm going to triple check my valvetrain geometry once I put my new 1.6 RR's on with the GM guideplates.

Dan