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Tips
Tips

Generator not working, took apart, what's next?

Brinkerhoff - I'm not sure exactly how or what to test next.

Coil - No voltage reading coming out of it when key is in.
White wire to coil - 12v with key in
No spark from top of coil with distributor wire removed when screwdriver tip is placed near and key is turned.

Thanks!
 
That's what I was doing (turning the key) when I had the screwdriver near coil and it produced no spark.
 
If you see 12 volts on the white wire while it is connected to the coil, disconnect the wire from the other side of the coil that goes to the distributor ( points )and then check for 12 volts on that terminal. If you don't have 12 volts then the primary side of the coil is open and you will need a new coil.
Another check is to look for 3 ohms across the primary terminals on the coil with all of the wires disconnected from the coil.
.....
If you see 12 volts from the coil terminal to ground when the
wire that goes to the points is disconnected, then the points are closed or the condenser is shorted. Perhaps the wire that goes to the points is shorted to ground inside of the distributor.
 
So I get 12 volts on the white wire with the key turned on. If I test the terminal that goes to the distributor when the white wire is connected, I get 12 volts when I ground it somewhere besides the ground on the coil. It seems as if the ground on my coil is not actually grounded. Does that matter?

I have not checked the points yet. What's the best way to check them?
 
Take the cap off , then rotor. Examine everything closely and try and get an understanding of whats going on inside the distributor. As the rotor shaft spins (counterclockwise) the point gap should open and close quite visably. Pry the moving point open with a thin bladed screwdriver and examine the actual point faces, which should be smooth. Also check for wiring issues there. Check contiunity through the circuit inside to make sure your 12v to your points is not grounding to the point spring which is easy to do . The only time I've ever had a Lucas coil fail in a British car ( 35 yrs.& 30 or so cars) was when it got hot and started misfiring. I'm not saying the coils not bad but don't overthink it either. The points & condensors are problematic in these cars, the coils, not so much.
 
I'd say it makes a bunch of difference! Sorry to tell you, but your Pertronix may be dead. If they are left switched on for any length of time with the engine not running or the distributor not turning, the coil can overheat and this in turn damage the ignitor.

However, let's be positive and hope that's not the case. You should have a two wires going to the Pertronix, connected to the low-voltage terminals on the coil. It is vitally important that these are connected the right way round! I have heard, though don't know for certain, that if you connect them the wrong way you burn out the ignitor pretty quickly. Assuming your car is negative earth, the red wire for the ignitor should be attached to the + terminal of the coil - the same one as the white wire you mention - and the black wire to the negative terminal.

Do you have a test lamp - a simple bulb in a holder with 2 leads so that the bulb will light when you have a circuit? If not I suggest you get or make one, then connect one side of the lamp to the distributor side of the coil (with the black ignitor wire) and the other side to ground. With all wires in place, ignition on, operate the starter and the light should blink on and off.

I can see why you didn't respond to posts above that talk about points and sparks and stuff - you have no points to spark!
 
Roger said:
... If they are left switched on for any length of time with the engine not running or the distributor not turning, the coil can overheat and this in turn damage the ignitor ...

At the risk of being you-know-what retentive, I believe this isn't quite correct. If the switch is left on, and the power transistor in the Pertronix happens to be in the forward-biased state, the current flow will cause the Pertronix to overheat and fail. The heating of the coil is incidental, but can cause damage to or failure of the coil as well.

I've talked to Pertronix tech support, they confirmed this was the case.
 
So after tinkering around, I think it's my plug wires. I tested the spark with an ignition tester at the coil and plug and I was getting a spark. The carbs are cleaned out and delivering fuel. I cleaned off the plugs and realized that my wires are really loose. Only one wire really "clicks" into the plug. I think that may be my problem. I've ordered a new distributor cap and plug wires. Hopefully this will solve my problem.

Thanks everyone!
 
Bob_Spidell said:
Roger said:
... If they are left switched on for any length of time with the engine not running or the distributor not turning, the coil can overheat and this in turn damage the ignitor ...

At the risk of being you-know-what retentive, I believe this isn't quite correct. If the switch is left on, and the power transistor in the Pertronix happens to be in the forward-biased state, the current flow will cause the Pertronix to overheat and fail. The heating of the coil is incidental, but can cause damage to or failure of the coil as well.

I've talked to Pertronix tech support, they confirmed this was the case.

Well, I was just quoting from what I remembered reading in the Pertronix installation instructions!
<span style="font-weight: bold">Q. What happens if I leave the ignition switch on when the engine is not
running?
A. This can cause you coil to overheat, which may cause permanent damage to the coil and the Ignitor™.</span>

So maybe Pertronix need to get their story straight!
 
Definitely a discrepancy between the FAQ and what I was told. I can't imagine how a hot coil would damage the unit--maybe if the primary wire got almost hot enough to melt. But, the current flow through the Ignitor with a few ohms resistance would make the unit very hot in a short time, and heat is bad news for solid state electronics.
 
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