Ballasted ignition coils...?

[Ren32]

Hi,

I'm in the process of wiring my car from scratch and have just wired in a Bosch Red ignition coil along with the correct ballast resistor. My problem is that when the ignition is switched on (without engine running) the resistor seems to get extremely hot (i.e. burnt my finger)? Is this normal? I'm running it with a contact breaker type distributor and am assuming that the engine has stopped with the contacts closed but not sure if they are meant to get this hot with or without the engine running?

Any words of experience or advice welcome.

Ren.

[GreenV8S]

Electronic ignition would cut power to the coil after a fraction of a second. Mechanical points will keep the power on indefinitely - leaving the ignition on with the engine stopped is a good way to fry the coil if you have this sort.

[Ren32]

GreenV8S said:

Electronic ignition would cut power to the coil after a fraction of a second. Mechanical points will keep the power on indefinitely - leaving the ignition on with the engine stopped is a good way to fry the coil if you have this sort.

Hi,

so just to clarify, is it just not ideal to run a ballasted coil with contact breakers then?

[GreenV8S]

Ballasted or not isn't the issue. If you don't have mechanical ignition the coil will be liable to overheat if you leave the ignition on with the engine stopped. It's no problem, just don't leave the ignition on with the engine stopped.

[Ren32]

Sorry, my misunderstanding.

Cheers for the advice.

[steve_D]

Back to the first Q. Yes it will get hot with the engine running but even more so if left with ignition on with points closed.

Steve

[Ren32]

Cheers for that Steve, I'll have a re-think and move it away from the rest of the loom.

Thanks,

Ren.

[steve_D]

Ren32 said:

Cheers for that Steve, I'll have a re-think and move it away from the rest of the loom. Thanks, Ren.

If it bolts on then bolt it to something metal to sink the heat away. It will be better for it. If it is a resistor wire then arrange it in free air, again so it has a chance to cool.

Steve