[boboman]

I have a 96 chevy lumina with a 3100 v6 engine. The engine has developed a valvetrain noise, like a chatter or tap. It resonates through the middle of the block, but can be picked up with a stethoscope through the timing chain cover and the bell housing. However, The noise is only present when the engine is not at operating temperature. When the engine warms up the noise goes away. I had an oil pressure test done and was told the oil pressure was good both cold and hot. But the mechanic I took it to said He could not pinpoint the noise without tearing down the upper part of the engine. But He suspected a lifter or timing chain to be the culprit. The engine does have a LIM leak. But I wouldnt think this would be the reason for the valvetrain noise. Does anyone out there have any suggestions? Also, I plan on doing the work myself, when I replace the LIM gasket, where do I apply the silicone at. I know it doesnt go on the whole gasket. Please help. Thanks.