<VV> The latest on the metallic rapping noise from my recently built 3.1

[Bob Gilbert 1]

Here is the latest.

 

I took both heads off and there is no visible damage or unusual marks on the
heads, on the top of the pistons or the cylinder walls from TDC to BDC

At this time all of the cylinders and pistons are still in place.

 

There were a few oddities, not sure if they are in any way related to the
noise but here goes:

 

At TDC The piston to cylinder gap on the passenger's side is .008 and .014
on the driver's side. FWIW, the piston skirt scoring is more prevalent on
the drivers side.

At BDC, the skirt to cylinder wall gap is .010

The pistons rise a few thousands of an inch above each cylinder. Visually
they look like they are even with the top of the barrel but I can just feel
the piston protruding with my fingernail. Although I didn't measure it, the
head gasket is (relatively speaking) much thicker so I wouldn't think that
there would be any interference.

All but one of the lower studs on the passenger's side came out. The threads
looked OK and there was no aluminum in the threads.

 

 

Any ideas?

 

Regards,

Bob

PS I had checked earlier and the studs were not interfering with anything
inside the crankcase.