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[Fot] Any connection between these problems?

To: fot@autox.team.net
Subject: [Fot] Any connection between these problems?
From: George Harmuth <harmug@us.ibm.com>
Date: Mon, 11 May 2009 13:35:37 -0400
I have a question for the massed knowledge here. I had my first race of the
season last weekend at Pocono. I was running a new engine, 1296, in my
spitfire. The engine had about 45 minutes of run time on it, in the garage
and up the driveway, nothing at load. 1/2 way around the first lap, when I
was going into 4th gear, short shifting while I broke in the motor,  around
7000 RPM, the motor cut out. I coasted to a stop, the engine would still
turn over but not run. Towed back to the pits, found the rotor in the
distributor, Delco-Remy, had split in half and fallen off the shaft. No
sign of any contact inside the distributor, new part for the season figured
it was defective. Replaced the rotor and the engine fired up. Heard a
rattle somewhere, noticed the harmonic balancer moving in and out a 1/4
inch. Shut it down and saw the nut was missing. Located it under the car,
must have just fallen off. Put it back on, checking to assure the key was
still on the shaft and tightened it up.

Fired it up again and the rattle was still there. Pulled the starter and
found play in the flywheel, would move back and forth 1/4 inch. We pulled
the tranny and found the flywheel bolts had loosened up. Pulled the wheel
and clutch off, cleaned and checked everything, all looks OK. Grabbed the
flywheel flange and it felt tight, no noticeable play in the shaft. I
didn't have a run out gauge at the track so I can't put a number on it but
the front and back of the crankshaft seemed to be tight. When I turned the
front, the back turned the same amount so I'm assuming the crank isn't
broken.Looked at the valve train, nothing out of the ordinary there either.
We decided to put it back together.

Cleaned up the parts, put fresh lube on the bolts (ARP) put them in finger
tight and the first bolt that had a wrench on it snapped off inside the
crank before the torque wrench went a 1/4 turn past finger tight. We
couldn't get the broken bolt out at the track so we packed it in for the
weekend. I'm assuming that the bolt broke because it had been stressed out
when the flywheel was loose and banging around.

My questions, are these separate, independent problems? Did the faulty
rotor save me from major damage due to sloppy assembly work with the
flywheel and crank nuts or can you think of a common cause for all three
problems?

Does anyone use tab washers for their racing engine flywheels? Loctite
doesn't seem practical since I don't dry assembly the flywheel bolt, I use
a lube and torque them 3 times as recommended by ARP. Should I go back to
Grade 8 hardware and drill holes so I can wire them together? Any other
suggestions?

thanks
mike

G. Michael Harmuth
63 Spit race car
70,72,79,80 Spitfire Road cars
70 GT6
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