For you technical buffs out there, this one is a stumper for me.
At Sears Point, October 28-29, I had an ignition problem that I'm at a loss
to resolve. The car is a series 1 Alpine with a series 5 (1725cc) engine, 12
volt with the polarity reversed to negative ground. The engine is basically
stock, with Zenith carbs and a Mallory dual point distributor. I'm also
using a Mallory ballast resistor.
On Saturday, in the rain, temperature around 65 degrees, the car ran
fantastic, easily attaining 6500rpm in 4'th gear. We finished 2'nd overall.
On Sunday, on a dry track with the temperature again around 65 degrees, the
performance was the same until the start of the 3'rd lap. At this point, as
I was entering turn 1, the engine stopped running..... just as if I had
turned the ignition off. All attempts at a restart failed.
After the end of the race when the tow truck arrived to tow me in, just for
kicks, I hit the starter and she came to life as though nothing had ever
gone wrong. I drove it around to the pits and up onto the trailer.
The next morning I fired it up and drove it off the trailer and into the
shop. It started right up but the ignition cut out if I tried to take it
over 2000rpm. The next day I started it and it ran through the entire rpm
range without hesitation.
The fuel system works fine; no problem here.
The timing was correct.
The ballast resister showed 1 ohm of resistance. The specs for the resistor
are 0.75 - 1.5 ohms, so no problem here.
I pulled the distributor and removed the points. One set of points showed
correct point gap and normal pitting for the amount of use. The other set of
points looked like they had been a plate for arc welding, with the entire
surface of the points badly pitted and rough. The gap appeared to be
correct; given the amount of pitting.
I replaced the points, condensor, ballast resistor, timed it and it runs
perfectly. Further inspection revealed one wire lead from the ballast
resistor to the coil that "wasn't as tight as I would like (but not falling
off, either)", which I tightened. Further, I inspected every wire and
connection between the engine and ground or back through the circuit to the
ignition/starting switches and no other problems.
Has anybody out there experienced similar problems? What was your cure?
Anybody have any idea what may have gone wrong? I'd sure hate to be at the
front of the pack again this weekend at Thunder Hill and have a similar
thing happen.
Thanks in advance!
Carl McLelland
email: carlmcle@saturnnet.com
web: http://carlynneracing.homestead.com/home.html
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