> Would I be correct in thinking this method has measured the
> fore and aft
> play of the crank?
Sounds reasonable to me.
> If so do I need to replace the thrust washer?
That would put you at .012", which according to my TR3 book is the wear
limit (actually .0117", but I won't quibble over a few 'tenths'). So yes,
I'd suggest replacing the thrust washers while you are in there. On a
TRactor motor, they are easy to change with the engine still in the car.
'New' clearance should be .004"-.006" (again according to the factory TR3
workshop manual, but I don't see why a TR4A would differ in this area).
If the thrusts are that worn, wouldn't hurt to have a look at the rod & main
bearings too. They can also be changed with the engine in place. One of
the shop manuals even suggests changing the rod bearings every 30,000 miles,
as preventative maintenance.
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