I recently purchased a 1990 Coupe L-98 with 39,000 original miles that had been in storage for several years. The engine runs fine but it sounds like it has lifter clatter. I replaced the lifters with Chevy high performance roller lifters along with rebuilt Bosch injectors and a new EGR valve while I was at it. I adjusted the lifters cold to factory settings (zero lash plus one turn) but the engine is still has a audible tinny clatter. I have never owned a TPI roller cammed Corvette before so I am wondering if what I'm hearing is the injectors clicking. The engine currently has Quaker State 10-40 oil in it with a quart of Lucas additive. The oil was changed after the work was done. Any help would be much appreciated.

 

My husband, the guy who keeps mine running says, " that is one of the "put the phone up close to the engine so I can hear it” problems, there is no way to really diagnose a noise without hearing it." lol...

 

I very much understand .......... I was mainly wondering just how noisy these Bosch fuel injectors are since I've had no experience with them. Thanks for the reply.

 

akfinn1a: Welcome to the forum.
The only way I could hear the injectors on my '87 IROC-Z was to use a mechanic's stethoscope. Does the clatter go away when the engine warms up? If so, it could be piston slap. Like Ladybug said, it's hard to diagnose without actually hearing the noise.

 

Did ya know that Quaker State and Penn have wax in 'em? I've seen wax an inch deep under the valve covers of an engine using only Penns or Quaker State. I use Castrol GTX 30 exclusively. As far as the clicking sound you are hearing, that's anybody's guess at this point.

 

Thanks 73 Shark.....I believe you just answered my question on injector noise. I think I'll run the valves one more time to be sure before looking elswhere for the noise. No worries C3 Starship ....... the Quaker State is temporary. I use Royal Purple in everything I own. I was just using the QS for a flush before putting in the expensive stuff! I am heartened by responses here and I am very happy I signed up.

 

I used Quaker State 10W40 in my '68 GTO for a 100,000 miles and experienced no wax build-up. Same with my '73 Corvette for 75,000 miles. YMMV

A quick review of Bob Is The Oil Guy forum and website will shed a lot of information on this topic.

Let us know what you finally figure out on this noise problem.

 

All I can say is what I found when I opened the engine up. It was a 454 out of a 78 Suburban, not my vehicle. The wax buildup almost completely covered the valve springs.

 

I'm surprised no one suggested using either a mechanics stethoscope or a long handled screwdriver and put it against the injectors, valve covers etc and see if the search area could be narrowed down.

Without hearing the noise plus narrowing the source of it down, it's hard to advise what might be the cause and what could fix it.

 

Re: mechanics stethoscope. See Post #4.
I agree that that would be very helpful in determining the location and source of the noise.