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Help - broke down on road - battery good but no power to starter

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BrandonBJ8

Jedi Trainee
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Was driving and turned up my radio a bit and hears a load pop followed by smoking from the radio. Car died to a stop. Popped trunk and found battery cable popped off. Put it on and turned key but no power. Battery is reading fine. Any ideas? Im stranded. Thanks!
 
Turn on the park lights so you can see if there is power and then wiggle the master switch back and forth while watching the lights. Try sticking a big screwdriver from the switch terminal to ground. Bypass the master switch by moving the battery lead onto the same terminal as the ground if it is being dodgy.
 
Silly me. Has the master power off. Car is trying to turn over now but sounds like no spark. I have petronix, could I have fried it? Any options?
 
Also might disconnect the small white/black wire either at the master switch or the coil. This wire grounds the coil from the master switch. Suggest routing battery ground directly to ground, bypassing the master switch.
 
often the switch goes dodgy. I have a NOS one and it is dodgy...

Look behind the master switch at the terminals and try to get something metal shorted across the two big terminals- if the park lights flash on while doing that then you need to somehow bypass the switch to get you home. Use a coin even.

If you have a jumper cable set then connect one from the rearward battery terminal to the chassis earth below the master switch. If not then try and unscrew one of the master switch cables and attach it onto the other terminal post to bypass the switch.

Check to see if the park lights come on first while shorting the switch, look elsewhere if they don't.
 
Sorry for the confusion but I turned off the switch when the car first died and then forgot to turn it back on. :smile: Now car is trying to turn over now but sounds like no spark. I have petronix, could I have fried it? Any options?
 
lol... do you have an alternator? That could fry a pertronix if it fried the radio. The Lucas ACR alternators tend to have very high voltage when the battery is disconnected. Spare set of points in the glovebox?
 
No alternator. Original generator. Unfortunately, no spare points. Can I tell visually if the petronix is fried? Never fried one before.
 
Probably not, although I've never fried one either.

If there is no spark from the coil when you put the dizzy-end of the centre lead near the engine and crank it over then it might be dead although I'd have thought they'd be fairly well immune to over voltage. Is there 12v at the coil with key on? Does the fuel pump still click as usual with the key on?
 
Replace distributor rotor - situation sounds like failures of riveted rotors a few years ago.
Replace coil

Fried Pertronix will display blisters on the label - according to engineer at Pertronix I spoke with.
 
10.4v would indicate some resistance in the ignition switch/wire supplying the coil and that the pertronix is conducting. This could be normal except that if the pertronix is always conducting when the engine rotates over then it could have a shorted transistor. There should be six places around the cycle where the pertronix is not conducting which is where the spark occurs. Your coil will probably be quite hot by now if you have had the key on for more than a few minutes.

If you pull off the -ve wire to the pertronix while measuring the voltage, does it go up to near the battery voltage? There should be a spark from the contact and maybe a small spark from the coil lead when you do that which would indicate the coil is ok and maybe the pertronix is not working right. (I'm guessing your car is -ve earth). Don't give yourself a shock from pulling the wire off...
 
At home after getting car towed.

When I pull of the neg wire off from the dizzy to coil the voltage of the coil drops from 10.3 to 0. What does that tell us?
 
It'd probably help if you describe your setup a bit better as there are many different ways to wire a pertronix. I can't picture what is happening when you pull the -ve wire off.

Is your car +ve or -ve earth?

What is the voltage at the white wire - it comes from the key switch and be approx 12v when removed from the coil with key on.

Does the coil get hot if you leave the key on for more than a minute?

How does your tachometer work (I"m assuming it is electronic rather than mechanical?) with the Pertronix?

What is done with the white/black wire that goes to the trunk switch? This should be disconnected for a -ve earth pertronix
 
My car is negative earth.

The voltage of the white wire is 12.2v when removed from the coil with the key on.

When I leave the key on for about a minute, the coil gets warm (not hot).

I believe the petronix and tech relationship is mechanical via the vacuum hose.

The white/black wire to the trunk switch is still connected. However, the car has been negative earth for years now and its always worked fine with that still connected.

Thanks for your help here
 
It does sound like your pertronix got damaged if power is getting to the coil ok but there is no spark. I'd ring Pertronix and explain what happened, they may even want your one back for analysis (assuming it is dead). I'd be interested to know the outcome.
 
Brandon -

I ran a quick Google search for "Pertronix Ignitor Test" and found this:

1. Connect a jumper wire from the Ignitor Plate to battery ground.
2. Connect the Red wire from the Ignitor to the battery positive terminal along with the red lead from a volt meter.
3. Attach the Black wire from the Ignitor to the black lead of the voltmeter.
4. Move or rotate the magnet sleeve in front of the Ignitor Module, the voltmeter should vary from battery voltage to 0 volts and back.
5. If it does not, then you possibly have a burned out Power Transistor or a failed Hall cell.

There is also a youtube video test on the web, but it is in a language other than english.
 
Went through the entire testing process with Pertronix and the ignitor is dead. Problem solved! Thanks for your help everyone.
 
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