Carl,
Read Carol Smith on flywheel retention. I redid a Sprite engine for a friend a
few years back that some "smart" person had used "Bowmalloy" bolts all through
it. The ones that had been installed to hold the flywheel, had for the most
part given up doing the job and were within minutes of doing what your bolts
did. This is not a place for brittle grade 8 bolts! I should have changed the
thread on my Climax crankshaft, when I had it made, but didn't so I am forced
to use socket head cap screws, which I customise, by taking longer ones with
unthreaded shanks and cutting them off to required length. I also replace them
fairly often. If you have dowel pins at this interface, replace them often
too. Cheap insurance!
Roger
>>> "Carl McLelland" <carlynneracing@home.com> 03/28/01 03:16AM >>>
To all "Alpiner's", and all vintage racers, regardless of what you
race!!
Last Sunday I was entering turn 10 at Sears Point, 2nd lap of practice
so I wasn't really up to speed yet, when I had a potentially life
threatening event occur. I had backed off momentarily to set the car
for the corner and when I came back on the power had the
flywheel/crankshaft bolts shear. I was turning 6000rpm in fourth at
the time..... a couple laps later and I would have been somewhere
between 6000 and 7000.
The engine went "instantly" to 9000rpm before I could (1) get my foot
off the "enthusiasm" and (2) shut off the fuel pump and ignition.
Somewhere between 6000 and 9000 the flywheel came off the crank flange
and started trying to grind itself out of the bell housing!
Fortunately for me, it wasn't successful. What am I leading up to?
1. I made a steel scatter shield some time back, which may have saved
me had the flywheel come through the bell housing (or had the flywheel
exploded). If you haven't done something to protect yourself, DO IT!
2. For you Alpiners, a friend of mine, having seen the photo's, is
dedicating himself to making some carbon fibre scatter shields that
will be bonded to the aluminum bell housing. This should add 3-4
pounds to the weight of the car, which is negligible. He presently has
10 bell housings, so they would be a manditory exchange (or I'm sure
he could make a scatter shield for your bell housing if you sent it
to him). Anyone who is interested in more detail of what happened, or
wants to see the photo's, (or just wants to tell me what a supurb
driver I am), please respond off-net and I'll forward the photo's.
I don't have a price for the carbon fibre bell housings yet, but you
can rest assured ones going to be installed on my car, in addition to
the steel one!!
Carl McLelland
CSRG #247 series 1 Sunbeam Alpine
CarLynne Racing LLC
carlynneracing@home.com
http://carlynneracing.homestead.com/home.html
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