4.3 Valve Train Noise

[cpayne3]

I have 2002 4.3 V6 that has some valve train noise. I pulled the left side valve cover and found that a rocker on cylinder #4 was loose. However it is tightened down all the way with no adjustment. I believe that this year motor has the hydraulic lifters and there is no adjustment. It looks like a collapsed lifter - but wanted to see what you guys thought before I start pulling things apart?

Thanks
Charles

 

[havasuboatman]

Re: 4.3 Valve Train Noise

You checked to make sure it's not just a bent pushrod, right?

 

[Bt Doctur]

Re: 4.3 Valve Train Noise

Or the stud pulling out,or broken valve spring

 

[cpayne3]

Re: 4.3 Valve Train Noise

The push rod does not appear to be bent and the rockers are the pedestal roller bearing type that have a bolt running through them into the head rather than a stud and nut. Not sure but as a result I believe the lifters and this set up are designed to be self adjusting. The valve spring itself looks to be a little lower than the rest but can't tell if that is just my perception or not. I guess I should probably start there rather than pulling the intake manifold for a lifter replacement?

 

[wilsoe02]

Re: 4.3 Valve Train Noise

If you have a valve spring that is lower than the other ones, you have a bent or stuck valve. This means that you will have to pull the heads that means that tou have to pull the intake also.

 

[havasuboatman]

Re: 4.3 Valve Train Noise

Rotate the engine so that the cyl with the suspect valve is at TDC of the compression stroke. pressurise that cyl with air and listen for leakage if you get no leaking, Probably bad lifter. If you hear air, bad valve