<VV> "Checking" for cam and lifter wear

[djtcz at comcast.net]

Original message 
From: "Ray Rodriguez III" < vairguy at echoes.net > 
Subject: Re: <VV> a different oil conversation 
........................ 
Is there any easy way to check an engine to see if it has already sustained 
significant wear of the cam lobes without taking the engine apart beyond 
valve covers and oil pan removal? .................. 

The conclusion I draw from this is that the ZDDP is probably a lot more 
important to engines built with new parts, particularly hi-po custom builds. 
Those with stock engines and original GM cams are far less likely to ever 
have a problem and might not concern themselves with the ZDDP issue. 
------------------------------ 

Jeg's and others have 1 inch travel dial indicators and mag bases for fairly short money. 
Mag bases are not useful on aluminum blox-n-heads, so a hunk or bar of something ferrous must be afixed to the engine first. 



Position the indicator parallel to the valve stem, and contacting a flat surface on the retainer. The measurement will be net valve lift ( cam lift X actual rocker ratio (-) who-knows-what for a little lifter leakdown) 
I'd probably rotate the engine thru many revolutions looking for repeatability even though only 2 revs are required to capture a full lift event. 


I am not at all confident a well seasoned low performance OEM cam in good running condition will never, ever need a splash of ZDDP, etc, when the oil temp is a little high and the viscosity at the rubbing surface happens to be just a little too thin, or the oil splishes instead of splashes and the quantity delivered is a little low, or slightly misplaced. Some of the lifters share lobes, so on one bank the lifter/cam interfaces only gets oil that is still clinging to the cam lobe after it has already run close by or even through the other bank's valve opening event.