After 3 years of sitting silently before I traded parts for it, I got my 87 xj6 to come back to life. I noticed pretty quickly that the resistor on the side of the coil began to smoke.
Anyone have any ideas why or where I should begin to look?

 

Jamey, I would venture to guess that through the years of sitting, the amount of resistance for that resistor went up, causing it to drop more voltage, therefore dropping more power, leading to the overheating issue. I would try putting in a new resistor and starting there.

The only other thing that it could possibly be is that if you are running an aftermarket "hot" coil (ie, higher voltage unit), that will cause the coil to draw more power, which will cause the stock resistor to run hotter.

Hope this explains what is going on. If the car is running, then I would highly doubt you have a bad coil as the bad coil should be causing the car at a minimum to be running rough, if at all.

 

it does run rough, but it hasn't run in 3 years. Probably wouldn't hurt to change the coil too.

 

Back in the '80s I noticed that almost every 1984 to 1987 XJ6 that came into the shop had a 'smoking' coil resistor (the metal covered one on the side of the coil).
If it's the stock French made coil (Unipart) then it is completely normal. I don't know if it is because they seep oil (you will see evidence on the wires and on the high tension lead boot) or because the French just like to smoke!! The only ones I saw that did not smoke were ones that had been replaced with U.S. 'STANDARD' or Lucas and the resistor had been eliminated. The oil in the coil (hey that rhymes!!!) will wick up into the resistor windings and when the resistor gets hot (that is what they do to dissipate energy) it will burn off the residual oil. Eventually it will leak enough that you will run out cooling fluid (oil) and the windings will overheat and burn. You might want to consider a new HE (high Energy) coil soon and save the GM ignition module from damage from a coil drawing too much current. (or you can rotate the coil so that the resistor is on top and might not get the oil on the resistor windings, hey no smoke, no worries)

bob gauff

 

So I can switch to a different coil and do away with the resistor? If so, can you tell me what to switch to, and what to do with the extra wires going to the resistor?

 

I worked at an independant British car repair shop and we had the Lucas coils in stock in the parts room. I don't remember the part number but I never put the resistor on the replacement coil. The V12 had 2 coils with the primary windings in parallel so I figured the ignition module could handle the single coil.

bob gauff

 

It looks like a typical coil used on so many different early model cars. So do you think a typical coil from an early GM (considering it uses a GM ignition amp) could handle it without the resistor? What do I do with the wires to the resistor, should I just connect them together?

 

All the wires that are on the + side of the coil go together and all the - go on the other. If I remember correctly the white/black (ignition amp) and the white/blue/black (tach wire) are the negative.

bob gauff