Sorry I am not directly answering your questions... they will probably not help.

I am going to address the broken crank idea though then give some hints as to where you should start in your search for noises.

The mention that the crank is broken is not far-fetched. The thrust bearing is more towards the front of the engine than the rear - any break behind the the thrust bearing carrier will not be fully detected by the observer when measuring axial play at the front of the engine.

They mean the crank is actually sheared into 2 pieces. If its really 1/8" than something terrible has happened. The spec is less than .3 mm.... yes, millimeters.



Some ideas assuming you actually measured 1/8" of axial crank play:

Remove the chain tensioner spring, Free the chain from the camshaft and suspend it tightly or have someone hold it under tension. Remove the vacuum pump. Advance the crank by hand then reverse slowly paying attention to changes in resistance. Repeat the advance and reversal at a faster speed... then move about 70 degrees on the crank and do it again.

Try running the engine with the vacuum pump and valve cover removed.

Drop the lower oil pan, wedge something between the crank and the block in different places and re-measure your crank end play again each time. Have someone do the wigglin' while you look at the crank.

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