MG Car Repair/ignition

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Question
I'm working on a. 1978Mg midget for a friend that won't turn over.I have replaced the battery and the starter solenoid. When I turn the key I get a yellow light on the dash, the solenoid clicks and the ground write on the block instantly gets red hot

Answer
Hi Tim,

Any time a cable gets hot it is because there is an excess of amperage going through the wire.
So if this is a ground cable it means the the starter motor is shorted out or the engine is locked up and the starter motor can't turn it.

The first thing to do is to put the car in 4th gear with the brake off and with the hood up so you can watch the fan blade, roll the car forward. If the fan blade turns easily, the next test is to follow the main battery cables.

The Battery (-# negative cable connects to the body of the car. The engine ground cable must be about as large as the battery cables and connect the engine case to the frame or body of the car. The #+# battery cable runs down to the starter solenoid. There are 2 large posts on the solenoid. One gets the battery #+# cable and the other gets the starter motor cable which is sometime a heavy strap that goes directly into the starter motor and must be insulated from the starter motor case.

If the engine turned freely when put in gear and push the car, then put it back into neutral and remove the #+) cable from the starter solenoid and just scratch the cable on the second large post of the solenoid that is connected to the starter motor. Be careful because it will make sparks but it should activate the starter motor and the motor should spin. If you get a lot of sparks and the starter motor does spin, you have a defective starter motor causing the problem.

Let me know,

Howard  

MG Car Repair

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Howard M. Fitzcharles III

Expertise

MG from 1956 (USA versions only) up and Engine theory.

Experience

Dealership line mechanic on MG, Triumph, Jaguar for 15 years, Instructor in commercial mechanics school 2 yr. Product information manager for piston and valve manufacture, Instructor & hotline answer man for import car parts importer 15 yrs.

Organizations
Associate member SAE EAA member

Publications
Import Car magazine

Education/Credentials
ASE Master Auto with L-1 certification up to 2000

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