QuestionQUESTION: hey there howard,
i am cureently restoring a 75 mg midget. the distributor was in bad shape so i went and got a distributor from a 74 spitfire out of the junkyard. now the spitfire distributor has breaker points, but the 75 mg midgets have electronic distributors. is that what is keeping the sparkplugs from
sparking? also i replaced the coil and on the positive side of the coil are two white wires twisted toghether with a green stripe on both of them and fastened to the positive post. one of those wires runs to the solenoid and im unsure where the other one goes. on the negitive side is a white wire with a black stripe on it going to the distributor. i also gaped the points and the spark plugs. so why wont it spark?
ANSWER: Hi Donovan,
It sounds like you got the wires correct but you need to do a couple of tests.
First disconnect the white w/black tracer wire from the dist. and turn on the ignition. Take a test light or volt meter and remove the coil tower wire from the distributor cap. Check the (+) side of the coil for power and the white w/black tracer wire for power. You should have 12 volts+ on both. then hold the coil tower wire about 1/8 of an inch from a metal part of the engine and scratch the white w/black wire across any engine metal part. You should see sparks at the end of the coil wire. If so turn the engine by hand so the points are open. Then scratch the white w/black wire on the post on the distributor. If it sparks you have a problem in the distributor and most likely the points assembly. If you get no sparks, attach the wire to the distributor and test the points arm for power with your test light. It must have power. If it does hold the coil wire again about 1/8 inch from a metal part of the engine and take a screw driver and short the points arm to any metal part of the inside of the distributor points plate. You should get a spark at the coil wire. If you do, remove the white w/black wire from the distributor and turn the engine by hand until the points are closed. Then hold the coil wire close to a metal part of the engine and scratch the white w/black wire on the post or spade on the dist. and watch for a spark at the coil wire. If you get a spark then the system is correct.
If you didn't get this far with the tests let me know what didn't go as I outlined.
Howard
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QUESTION: ok. the test lamp that i own looks like a screwdriver. the handle has a lamp and a wire running out with a red clamp on the end. the tip of the "screwdriver" test lamp is just a point that you touch the item your testing with and the red clamp is for grounding. i performed the very first test by grounding the lamp to the engine head. then, since my battery is almost out and wont turn the engine over using the key, i turned the engine over with jumper cables, the battery and the solenoid. while the engine was turning i touched the positive side of the coil with the test lamp point and didnt get a light. I DONT UNDERSTAND BECAUSE I JUST REPLACED THE COIL!!! so thats as far as i got. i already failed the first of your tests. PLEASE HELP!
thanks,
donovan
AnswerIf the key was on and you had no power to the coil on the (+) post, it has nothing to do with the coil. It has to do with the wiring or ignition switch. You need a wiring diagram to test the circuits up to the coil (+) post.
A coil can't operate if it is not powered.
Howard
