Hello TR folks.
I have a question that is a little "wider" than just Trimphs but thought
I would start here. Having performed a timing-chain-cover-oil-seal
replacement on a friends Spitfire yesterday, the question of torque
came up. The big nut that holds the pulley on the crank was
(as you know) very tight. 150 foot-pounds according to shop manual.
Removal entailed abandoning first attempt and re-convening another
day with a "hoss" 3/4 drive impact wrench. The first attempt was
a good 3 hours of SWORK and we had a good-for-most-jobs impact
wrench.
To make a <already-getting-to-long> story shorter:
upon re-assembly, we reflected upon the <proper pre-load of
fasteners> duly noted from recent BCD reading. My question is
(at last) How does one torque this nut to spec? With a torque
wrench? The motor turns over at far less than the desired torque.
With the car-in-4th-gear-person-inside-all-brakes-on-hard, we get
the "mechanics feeling" that something (like the clutch or tranny)
will snap before we reach spec torque. (same feelings during aborted
first removal attempt) Is there such a thing as
a calibrated impact wrench? We are running around with a less-
than-tight-front-nut.
Bob (pondering-preload) Sykes
75, 78, 78 Spits
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