Hello,
I'm trying to find what causes this sharp intermittent noise, when valves cannot be the cause. I cannot figure out where it is coming from. And I know noone who would use a stethoscope.
It is especially there when cold, and is quite bright. You can hear it at idle, and even warm, but then it is less bright. Sometimes it is there when accelerating, not all the time, more when cold. When revving up at idle, there's also a short moment of intense rattling, just when the rpm lowers again. The frequency makes me think it is on all cylinders. Someone said it could be a "floating valve". I think I heard that with respect to racing cams. Also I heard piston wear could cause this. It may be possible advance ignition was set at a lower level, would this cause piston wear and this noise ? I heard other wear, bearings, would be lowered through this setting. On the other hand, pushrod shells were the first thing I thought of.
I will try and find more about this on usenet, but I'd appreciate any comments,
Thank you,
Peter