427 rebuild and lifter noise
69: Recently found a bad head gasket on my 427/390 engine so had it checked and decided to go ahead and freshen up whatever was needed (engine bearings, valves, valve guides, etc.). We primed the engine until oil was present in all the lifters then started the engine. We have only ran it in small intervals for a total time of ~15 minutes. The engine sounds great but can hear a little bit of lifter noise. Could this be a characteristic of the hydraulic lifters or need to adjust spring tension or should I expect this?
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Re: 427 rebuild and lifter noise
We did remove the lifters but put each lifter and rod back in the same location. We did not replace the cam, crank, or rods. 2 of the piston heads were slightly scored so changed those. The timing chain was also sloppy so replaced that and the valve guides were very worn so replaced those as well.Comment
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Re: 427 rebuild and lifter noise
Shawn------
Well, I'd say your lifter noise might just be there because you don't have all the valves adjusted properly. I use 3/4" of a turn down from zero lash. Spec is one turn down from zero lash. I think it's best to do the adjustment with the engine OFF and following the procedure described in the Chevrolet Service Manual.In Appreciation of John HinckleyComment
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Re: 427 rebuild and lifter noise
Joe - I appreciate the feedback. Was curious if there was a time expectation for hydraulic lifters to adjust after a rebuild. We did adjust the valves 3/4 of a turn from zero lash but may need to listen to each one and adjust as needed.Comment
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Re: 427 rebuild and lifter noise
Shawn------
With hydraulic lifters there is basically a range of adjustment within which there should be no lifter noise problem. You would have to be out of the range to experience noise caused by adjustment. As far as time for things to normalize, it should be very brief----like seconds and not hours.In Appreciation of John HinckleyComment
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