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zephyrdave

39 lincoln v12 spark problem

7 posts in this topic

The weirdest thing, took the car for its first shake down drive. After about 5 minutes the engine started to run rough. Came home, pulled each plug wire off, one at a time, with engine running. Passenger side had good spark from each wire to each plug. Driver side had poor spark from each wire to spark plug. The spark plug wires are new. I put on a different coil and changed the condensors from side to side, still the same thing. How can this happen when each side of the distributor fires both sides of the engine. This may be nothing to do with it, but the iron heads are coated with ceramic header coating. The battery cable is grounded to the passenger side head. I wonder if the driver side head is not grounded enough? I'm stumped.

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I doubt the threads for the plugs are coated but if the coating is under all the head nuts you might try removing the coating under at least one of them. I think I'd check the distributor again, check the left side points and the rotor.

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very carefully unhook the coil, lift it off...straight up..I would be very suspicious of the

delicate coil brushes..and spring..they need to stick out 1/8 inch or so ..with spring pressure

also, peer into the dist look for distress, metal, dirt, grease?? I am a little "solvent" crazy, and might spray

contact / elect cleaner, pull plates off dist..recheck fit..How were the brushes??

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After running the engine with another old coil I have, the spark began to return to the drivers side. I also read that the left and right coils serve their respective sides of the motor, even though the wires go to both sides. That leads me to believe that one side of the former coil was bad. I now have spark on both sides, but at higher speeds the engine seems a little rough. Maybe these old coils lose some spark with heat and engine load.

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I had the same thing happen to me last year. Turned out to be a new condenser went bad .

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Dave, you changed enough items without much improvement so I'd take a look at the distributor points. Couple of things I've come across: The spring on the points comes extremely close to the points mounting screws. Check also for lube contamination and sticking points. I've had new points actually stick on the axis stud.

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I bought two 6 volt coils with internal resister to make my own coil assembly. I know rebuilds are available, but I just want to try it myself. I guess I will have to bypass the resistors under the dash? During the winter I will remove the whole distributor and inspect all the internals.

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