Zoltan wrote
I still do not know the way big end bearings should be tested

Zoltan
the rod bearing when worn shows the cooper layer.
to test the rod it must be removed from the engine and assembled and
torqued to at least 33 ftpds
you could leave the bearing in and and measure it that way and get a
clearance to the crank journal or without the bearing and check the size
and out of round of the rod itself. The tool I use is a sunnen AG 300
micrometer it is accurate to .0001ths and is made to measure rod bushing
and big end sizes. most machine shops that can rebuild rods have this
mic at the price of $1300 last I checked.  Measuring the rod big end
bearing clearance with plastigauge only gives you one dimension and does
not help you if the rod big end is out of round. the milage is the a
good way to know if its time the 150k mark is a sound number to go by
the rods are done at this piont.
hope this helps
Bob Donalds
as always
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