Experience with Mallory twin point distributor.

Out for a run in my 100\6 yesterday. It had an occasional miss fire and once a total loss of engine power. But 99.5 % of the time she ran like a train. Having a look over the usual suspects this morning I removed the dizzy cap to physically inspect and basic gap the twin points before setting the dwell. I was surprised to find the center carbon brush fell into two parts and had been arcing over the rotor arm judging by the witness marks and carbon dust.

DW used to sell new brushes but they are currently not obtainable, I had to seeing for a whole new dizzy cap.

I wondered if this a common problem or was I just unlucky......hoping this is the cause of the miss fire , but I'm pretty confident...

Andy

I've had a Mallory Dual-Point distributor from Moss Motors in my BJ8 since June 1992 (102,000 miles) and I've never had any problem with the cap or anything else.

Pretty much the same here - I installed mine about 2000 and even though I have always carried a spare cap & rotor, I've never needed them.
Dave

Well some of the problem may be due to one of the old rotors that had a rivet in it , they would break down and cause arching of the rotor arm.

Keoke, the rotor in the Mallory Dual-Point is different from the rotor in the Lucas distributor. The problems were with the Lucas rotor -- or the modern reproduction of the original Lucas rotor.

Thanks guys, I'll put it down to poor luck , nothing else was wrong so its good to have found the problem.
I am driving up to the Good wood Revival in early September, it'd be a shame to have an undiagnosed problem hanging around.

Andy