Hello all,

I have a 94 Z28. the motor was rebuilt before i bought the car. It has about 4000 miles on it now. Here is the description of the problem i am having with it:

car runs fine when it is cold. It doesn't tick. Oil pressure is around 50 psi at 2000 rpm

As the car warms up it start a very noticable metallic rapping noise. It does it mostly at idel. if you rev it up to about 1400RPM it stops and then does it again around 2k rpm's Oil pressure when warm (180-200) is about 40 PSI. My mechanic says that it sounds like a bad wrist pin. To me it sounds more like something in the valve train. A bent pushrod or bad lifter.

The former owner had a hot cam put in. The only things that are not stock is the valve springs and the cam. Everything else it stock. I was think that maybe the stock pushrods were not strong enough for the increase in valve spring presure and bent a little causing th noise. I know have Crane Gold race rocker Harndend pushrods and hardend guide plates. I was going to put those on and see if that cure my ticking problem but i don't want to waste the time if the motor is going to have to come out for a rebuild ( if i decide to keep it)

Thanks
Shawn

 

If it is a wrist pin the very last thing you want to do is rev up the motor or drive it anywhere. Pull the covers and start looking for the problem.

 

well i hope it wasn't a wrist pin then because i drove it around with it ticking for a month or so. My mechanic is about a half ***. I guess i will just have to start looking myself.

thanks
Shawn