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MG TD TF 1500 - NO SPARK

I am perplexed. I am trying to start a newly rebuilt motor. The motor turns over great but I have no spark at the plugs nor from the coil wire. The coil and plug wires have good continuity. The coil is new. I have a petronix system in the distributor and the connections seem correct...black wire from petronix and white from block A-3 on regulator to the sw or negative side of the coil and the red wire from the petronix to the cb or positive side. All other electrical devices, lights, horn, etc work fine. I have little hair left and what I do have I have been pulling out. Can anyone shed some light on what I might consider and save my hair?
J FLESHMAN

J Petronix uses a strange connection system in cars with a positive ground. You did not state which way your car is wired so I can not give you any clues as to what to look for.

On a negative ground car the red wire goes to +12 volts which is the white wire on the coil. The black wire goes to the other coil terminal.

Give us some more details and I'm sure somebody on here can help you find the problem.
Cheers,
Bob
R. K. (Bob) Jeffers

I believe if Petronix is wired wrong even for a second, the unit is toast? Is there power going into it?
gblawson - TD#27667

THE CAR IS A NEGATIVE GROUND.
J FLESHMAN

See http://www.ttalk.info/Tech/pertronix_igniters.htm for a bit about Pertronix installation. The red wire from the Igniter and the white wire are common and go to one side of the coil (the hot side). The black wire from the igniter goes to the other coil terminal.
Bud Krueger

Take the hot wire off of the coil, use meter or test light to make sure bulb lights or you have 12V. Put it back on, remove the ground side (to the dist.). Make a temporary ground wire and attach to the coil- touch it to your ground point, and make sure you get a good HT spark. That way you know the coil is good. With 12V to hot, and a good coil, that leaves the Petronix suspect. Make sure the distributor is in fact turning as well. IF that doesn't work, put the points back in and try that.George
George Butz

This thread was discussed on 04/05/2007

MG TD TF 1500 index

This thread is from the archive. The Live MG TD TF 1500 BBS is active now.