>Hi Dick,
>
>Remind me to stand well clear of any engine John McEwen has recently put
>together!
>
>The usual methed of torquing the crank bolt/nut is to remove the starter
>motor and jam the fly wheel with a suitably large screw driver. This is
>also the best method, IMHO, for removing the crank bolt.
Hi John:
Obviously, I would not use an impact wrench for delicate work, but if you
have not using air tools to disassemble and assemble engines you are
donating a lot of time you can't get back. Most professionals use air
tools today because they save time, and wear and tear on the body. Final
torquing is still done by torque wrench but massive bolts are still most
easily, and safely, done by air wrench. The knowledge and experience of
the assembler is the single biggest guarantee. BTW, I am still running
engines which I assembled 20 years ago and have had no failures of any
sort. I rebuilt the engine in my van 5 years ago and have put 20,000 hard
miles on it pulling a heavy trailer while transporting two large
motorcycles. No problems and it was assembled exclusively with air tools
plus a final torquing with torque wrench where necessary. My MG was
restored two years and 6,000 miles ago. It has needed no adjustments or
wrench work of any sort since.
I would not recommend locking an engine by jamming anything in the ring
gear. A failure here would be truly expensive to repair. This sounds more
like a good old-fashioned bodge. An air wrench applies its force quickly
and directly to the bolt. It loosens the interference by the sudden force
which utilizes the inertia of the crankshaft mass. Slow pressure from a
wrench only succeeds in defeating that inertia.
John
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