Upgrade Coil ??

[Mike Meyer]

Hi All,
Some time back I replaced the points in my 1995 4.2 GLS with a Pertronix ? electronic unit. I've been very happy with that decision (especially as far as starting is concerned) but I think I may be cooking the coil. I've replaced 2 so far and I'm now experiencing an ominous misfire similar to that that heralded the previous failures.
I did not change to the "flamethrower coil " or whatever it is called.
I've had no success contacting the guy who sold the unit, (I think his name was Bruce - in Capetown, but the email address I have did not get me a reply.)
Does anyone have current contact details for Bruce or another supplier? .Alternatively can anyone recommend a coil that is suitable?
As another alternative, have I misdiagnosed the problem and should I look elsewhere for the cause of the misfire ?

Mike Meyer

[Tinus lotz]

Mike are your risistor stil in place? I know peter connan had a simular prolem but got the correct rating let him give you the correct answer

[Peter Connan]

Mike, I have indeed had a similar problem, but it seems the electronic ignition is not the cause.

In my car, the coil had been moved from on top of the wheel arch to the inside surface becaue of the fitment of an auxhilliary battery. Also, the resistor had failed, and been bridged out (but not removed). However I did not realize that it had failed...

When I fitted the electronics, I did tried plumbing in the resistor, but the car would start and then die immediately... | just bridged it out again.

Then the coil died, and I replaced it with a pirate. This lasted two weeks, so I replaced it with a genuine Nissan coil. This lasted about a year, then died on the way to the Kgalagadi. I then had several long discussions with Driko (grootseun) and the upshot is the following:

The resistor drops the voltage to the coil to about 11 volt, but it is by-passed by the ignition lock during starting to circumvent the voltage drop caused by cranking. The Nissan coil is designed to work on the lower voltage, and thus if used without the resistor will not last very long.

However, very few aftermarket coils these days are designed for use with resistors, and these will misfire with a resistor in place.

Also, a coil should be mounted in as cool an area as possible. Mine is now mounted next to the radiator.

Hope that helps?

[bogeyman]

The older system uses a 9v coil with a resistor for running and a bypass connection from the starter to 12v to increase spark during starting.
A good quality 12v coil mounted in a cool area without the resistor should not fail.

[AndriesS]

Normally petronix units requires a minimum coil resistance. Could the coils burn due to the coil not having the right resistance? Also try and mount it on the non exhaust side.

[Peter Connan]

Also try and mount it on the non exhaust side.

Rather not, there's petrol there. Just get it as far from the exhaust as possible...

[Mike Meyer]

Thanks all for the input. I'll take a look at/for the resistor. Coil is currently mounted on the left and I reckon about as far from the exhaust as possible on that side. Peter's comment about petrol on the right noted, so I won't go that route. Will also see if I can find a cooler spot.
Thanks again
Mike

[AndriesS]

But Petrol will cool it down :-) Jokes aside I once had a fire when the brass ferule on the petrol pump popped out and as luck would have it it was on the pressure side. That said I believe the alternator started the fight , I mean fire. The alternator, distributor, coil etc was on the same side but the the distributor, coil and wires was checked at night and there was no sparking.