[Fot] Any connection between these problems?

[Geoff Byrne]

Check that the crank is not broken through the rear main if its not it most 
probable will in future . Have it crack tested and checked for straightness.
The motor will run OK with a diagonal break through rear main
----- Original Message ----- 
From: "George Harmuth" <harmug at us.ibm.com>
To: <fot at autox.team.net>
Sent: Tuesday, May 12, 2009 3:35 AM
Subject: [Fot] Any connection between these problems?


>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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