Hot Rod Forum banner

1 - 3 of 3 Posts

·
Registered
Joined
·
495 Posts
Discussion Starter #1
Just build up a Buick 3.8 turbo engine. New cam and lifters hyd flat tappet. (comp cam kit). Broke in per specs. W/ goodvr1 20w50 oil and zddp additive Put a good 500 miles on the rebuild. No issues.

Took the car to the race track (1/4 mile). Made a few passes and developed what sounds like a sticky lifter. I reved the engine a good 6-8 times to 5500 and the sound went away. Made 2 more passes and drove home.

Started the engine up the next day and once warm the same tick was back. This is a very noticeable tick coming from the pass. side. Sounds just like a flattened hyd lifter. Ran 2 qts of rislone for roughly 40 miles. Sound went away. Started the car up the next morning and it's back!

So far I have pulled each wire on each cylinder one at a time and the noise continued. So I figured I could rule out the top end? (bearings/piston pins etc. )

Tore the intake off today and all the lifters/lifter faces look great. Broke down all lifters and cleaned. They were all spotless and pumped up very firmly.

Pulled the oil filter and split it. No metal. Oil pressure is great. 80psi on cold startup. Settles to 20 once warm. Ticking starts like clock work now at 40psi or so as the eng warms up. If I drive the car a few miles it seems to come and go intermittently.

I'm out of ideas. Pulling the pan today. maybe I'll find something odd in there.

ANY IDEAS? :confused:

On a side note the car ran amazing at the track. 10.78 @ 128 at only 19psi of boost. :)
 

·
Registered
Joined
·
495 Posts
Discussion Starter #3
Thanks for the tip... I did the roll test on a pane of glass and they are all true. Also pulled the pan and checked all rod bearings. They look great. There was a tad more alum flake in the pan than I like to see, but no slivers and nothing magnetic. This is the first time the pan has been dropped too. I don't think that amount of metal is out of the ordinary. I haven't checked the mains yet, but I highly doubt they would be an issue. If the cam wiped I think I would have magnetic shavings? Or some indication on the lifter faces?

The pistons are forged alum. But if it were a pin wouldn't the noise be constant? Also when I unplugged the wire going the the bad cyl wouldn't the tick have stopped?



I'm stumped!
 
1 - 3 of 3 Posts
Top