My wagon has been fitted with Luminition by a previous owner. Since I've had it, the ballast resistor next to the coil has been disconnected (or rather only opne wire going to it).
Not really an expert in the field of ignition systems, so does anyone know if the ballast resistor is required with electronic ignition? and if it is, what colours are the wires etc to connect it (photo of wiring to resistor/coil would be great if poss).
Got to admit that I don't even know what a ballast resistor does, and if it'll make any difference to running etc. Need educating.
Whether you need the ballast resistor would depend on the coil.
Standard setup has a 6V coil and drops 6V across the ballast resistor. When
cranking, a secondary contact on the solenoid puts full battery volts (less
than 12v due to cranking load) onto the coil side of the ballast resistor to
boost the spark.
I'd have thought running a 6V coil from 12V all the time would result in
overheating of the coil. A friend had a Rangie with Lumenition and that still
had a ballast, though in the form of a wire rather than a separate resistor.
That actually makes sense to me. Cheers for that. I looked at the wiring diagram and I couldn't make out why there was a feed from the starter motor.
If I'm getting it straight, the ballast resistor drops the voltage to 6v to the coil, so mine has been running at 12v all the time. I have only had to replace the coil once in 10 years, but it must have some effect.
This might sound a daft question, but if mine has been running with a stronger than normal spark (as per your description db) would that make it difficult to get the mixture setting correct or stable?
I'm not sure that the spark would necessarily be 'stronger than normal' if the coil was running on 12V. The idea is more to stop it becoming weaker than normal when the battery voltage drops during cranking.
Hopefully then if I reconnect it, the engine should theoretically fire easier and possibly fire up quicker (ie. less time cranking).
Do you know if the resistor gets very warm in use (I think I already know the answer to this )? The reason I ask, is that I had the coil mounted in a tupperware box screwed to the inner wing. I used to put the lid on it when I was off road to stop water getting to the coil. The resistor was mounted on a bracket with the coil and I don't want it melting through the box or worse.
I had some trouble with my ballast resistor. It had 'gone high' as they say in electronic terms and was at about 3ohms. This made starting very difficult because on my 110 the 'boost' feed direct to the coil during cranking doesn't work so it was was only getting a weedy spark.
This also started to affect normal running, where a noticeable improvement in performance could be gained by shorting the restistor out with a length of wire.
To replace it, I looked up some specs for mallory coils (which mine has) and found they recommend a 1.5ohm resistor.
Being a cheapskate I decided to do my own resistor and bought some 1.5watt ceramic bodied wirewounds from Maplin. I worked out the values for two in parallel and once these were soldered together with terminal fitted they have worked fine.
So to get to the point, I found that these (and the original resistor) only get 'hot to touch' during use and have never been too hot to hold continually with bare fingers.
I still need to sort out the direct cranking feed to the coil one day, but in the meantime having a correct value restistor means it starts ok anyway.
