To all who requested the XPAG/XPEG fastener list, I also included the
list of torque specs that I worked up from the shop manual, Woods
special tuning manual, scool of hard knocks and by picking the brains of
several long time engine (XPAG/XPEG) rebuilders. The shop manual and
the Woods manual are both wrong on the torque value for the gudgeon pin
clamp bolt. The value of 33 lb/ft given in those books is about 30%
over torque. The result of using that value when installing the clamp
bolt can be (was in my case) a broken bolt about 5000 miles after the
rebuild. In my case the bolt broke while I was doing about 4200 RPM on
the interstate. The bottom line was a grown man crying by the side of
the road and a new (expensive) engine. After being told by a retired
race car mechanic that this was a very common occurance in the bad old
days and it usually was the result of over torque of the pinch bolt (he
even told me which cylinders were the most common to go - hitting mine
right on the head), I started to do some research and came up with what
is considered safe torque values for bolts in the engine. Note that the
big end bolt is the same size and grade as the gudgeon pinch bolt, but
the torque for it is only 27 lb/ft - hmmmm! That really got me to
thinking. If this list saves someone from the same experience as I had,
it is well worth the time I spent on it.
Cheers,
Dave
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