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MG MGB Technical - electrical fire

I need help in solving an electrical problem that resulted in engine-area fire today.

Went to start the car (74B stock engine except for Ignitor in distributor) and noticed no ticking from fuel pump but continued to crank starter anyway. Starter cranked engine but no firing; tried again, same results. Went under bonnet, and saw red wire from Ignitor to ignition coil pos. terminal in flames and a white wire from the coil pos. terminal to fuse box (third fuse from top) with insulation melted and smoking. Connections on coil neg. terminal (a black wire from Ignitor and a double white wire from harness), were OK. Wires to starter and fuel pump also OK.

I'm no auto electrician, what do you caused this? thanks in advance.
William

A short or faulty connections probably caused it. Insulation on wiring in the engine compartment may have deteriorated due to age, heat, and/or worn through in some area.
Common area for poor connections is at the starter. Connectors may be loose and/or corroded causing a lot of heat due to high resistance.
To Fix: Check, clean or replace all connectors. Replace all questionable wire. Look for cracked or brittle insulation.
Kimberly

William - Check in the distributor the red wire on the ignitor rubbing against something. Things are pretty tight in there and the wires for the ignitor can wind up rubbing against the cam in the distributor. If left for any length of time with this condition existing, the insulation on the wire will wear through, shorting the 12 volts from the ignition to ground and causing the red wirre onthe ignitor and the wihte wire on the coil to burn. I put a small cable clamp in the distributor of our MGB to prevent just this kind of a situation with the ignitor wires. Good luck - Dave
David DuBois

This thread was discussed between 25/07/2004 and 26/07/2004

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