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Ignition Failure

RDKeysor

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My '60 BN7 went dead while driving today. Plenty of fuel, the filter bowl was full, and nothing obvious. I think it's an ignition issue and will pull a plug and check for spark. Any other suggestions?
 
My '60 BN7 went dead while driving today. Plenty of fuel, the filter bowl was full, and nothing obvious. I think it's an ignition issue and will pull a plug and check for spark. Any other suggestions?
Good place to start with sparkplug firing.
Check the Battery Shut Off switch to see if the white/black wire is hooked up correctly and not loose and grounding anywhere on the chassis.
 
Couple other possibilities:

1. carb jets clogged.

2. engine ground cable loose/corroded

3. loose low-voltage wire on distributor

4. dead condenser and/or coil (coils often "slowly die until useless")

5. generator/alternator failing, or loose wires preventing battery charging, and thus, voltage too low to spark

6. distributor clamp loosened, so distributor has rotated in the socket causing time to be totally "out of whack"
 
Did it stumble/shutter to a stop (usually fuel related) or cut off totally and instantly (usually ignition/electrical related) ?
 
The car was running perfectly and lost power during acceleration at about 25 mph. I had driven about 20 miles at that point. As it died, I tried putting it back into gear for a rolling restart without success. After it came to a stop, it cranked vigorously without any sign of firing. Under the hood the filter bowl appeared to be full. There was plenty of gas. I'm now looking for information on how I can test the electronic ignition system (and as suggested by another forum member, the coil). I might add that AAA managed to leave me stranded for four hours, sending a lift from a town so distant that the driver had no idea where I was. On the plus side, the lift driver was competent and got the car home for me. Now for the confession that may be relevant. I had been working on the car's electrical system for several days, issues with turn signals and the PO's lighting applied to the reflectors above the tail lights. Everything was again functioning. I was aware that it is risky to leave the ignition turned on when the car isn't running. I have two electrical shutdowns on my car, the one in the boot and a breaker under the hood that many in our Healey club installed. Despite constant switching the car off and on to avoid burning out the ignition electronics, I came out one morning and found I had left the car overnight with ignition on. I have driven the car several time since this blunder, but know it could be the origin of the Pertronix ignition--if that the was the cause and want it on the record. At 86 there are signs of slippage.
 
you got it - leaving the coil and pertronix energized without running the engine - not good.

At 76, my slippage is growing increasingly problematic!
 
Remove the wire from the coil to the distributor cap at the distributor and see if you get a spark from the coil. If you get a spark from the coil, it would be the distributor cap or rotor. If you don't get a spark from the coil, it may be the coil or Pertronix. Make sure you're getting voltage to the Pertronix.
 
I went to the car in the garage this afternoon intending to turn the engine over for a minute or so to check for fuel on a plug and then grounding the plug on the block to check for spark. You guessed it, about 26 hours after it abruptly quit running, the engine started up promptly and ran perfectly well. I ran it for a couple of minutes at about 1500 rpm and then let it settle into idle about 900 rpm. It usually idles a bit higher despite my efforts to get it under 1000 rpm. Now what? I am a bit apprehensive about driving the car for fear of a repeat episode. I also have to wonder whether it might have started during my four-hour wait for the lift. I don't have a clue but am glad I don't have to buy a new Pertronix ignition kit, that being my wrong guess as having failed. Interested in opinions. Thanks to the forum members and their responses, all of which merited my consideration
 
Check your wire connections. If you have any crimp connectors make sure they are tight and have enough strands of wire into the connector. I bought an old Chevy pickup many years ago and it would die after 20 -30 minutes of driving. I changed everything and it kept doing it. Finally, I pulled the wires at a butt connector to the coil and it moved ever so slightly. It was barely hanging on.. As the resistance in the wire strands would build it would heat up lose continuity, and the engine would die.
 
I started this thread and want to report the outcome. I first replaced the fuel filter and soon had another engine quit. The car had a generic fuel pump when I bought it a decade back, so I replaced it with and identical (but Chinese made) pump that ran for a few days before failing. I then replaced the pump with an identical pump from another eBay supplier and the car, a '60 BN7, has run perfectly until . . . over the weekend the car started and then quit abruptly in my driveway. It didn't cough or anything. Just quit. Spinning the engine, I pulled a plug and could smell gasoline. Grounded the plug and got no spark. Just for the heck of it, I replaced a newly installed coil with the old coil. Switch on, test light ground attached, I have power at the positive terminal on the coil. Still no start. I again suspect the Pertronix, which had I abused by accidentally leaving the ignition switch on overnight with no apparent damage. The car, aside from the fuel pump issue, has run well since that event. I am now looking to test the Pertronix ignition, which was in place when I bought the car.
 
Just this past week I experienced sudden engine stoppage while driving. No popping, nothing. I coasted to the shoulder and figured it had to be electrical. It cranked fine, fuel pump ticked. As I opened the bonnet, it began to rain...unusual for our area in August. I figured it might be a bad omen. My first motion was to tug on the high voltage wire from the coil to the distributor and it slid out of the screw in cap on the dist. with no resistance. The solid wires were flish with the end of the insulation and the small washer that the bare wires goes through remained in the tower. It took few seconds to remove the cap and shake out the washer, which I promptly lost in the dirt. I wasnt far from home so I just cut away some insulation, exposed a couple of mm of wire and shoved it back in and screwed in the cap. Fired right up. Later I found one spark plug wire with the same issue, it just hadn't backed out enough to cause a misfire.
 
I started this thread and want to report the outcome. I first replaced the fuel filter and soon had another engine quit. The car had a generic fuel pump when I bought it a decade back, so I replaced it with and identical (but Chinese made) pump that ran for a few days before failing. I then replaced the pump with an identical pump from another eBay supplier and the car, a '60 BN7, has run perfectly until . . . over the weekend the car started and then quit abruptly in my driveway. It didn't cough or anything. Just quit. Spinning the engine, I pulled a plug and could smell gasoline. Grounded the plug and got no spark. Just for the heck of it, I replaced a newly installed coil with the old coil. Switch on, test light ground attached, I have power at the positive terminal on the coil. Still no start. I again suspect the Pertronix, which had I abused by accidentally leaving the ignition switch on overnight with no apparent damage. The car, aside from the fuel pump issue, has run well since that event. I am now looking to test the Pertronix ignition, which was in place when I bought the car.
Go to the Pertronix website for their troubleshooting section. You can also call their tech support guy too! Pertronix has to have good minimum voltage and an excellent ground.
 
I've never seen a schematic of a Pertronix--trade secret, I assume--but I think it's basically a power transistor switched by a Hall Effect sensor, and likely some timing circuitry to produce the consistent spark (which gives the somewhat improved performance). If so, it's a 'roll of the dice:' if the engine stops with the transistor forward biased and the key left in 'run' you will likely fry the transistor; if not, it might endure an overnight event. Everything I've heard about them is that, if they fail, it's permanent; i.e. they work or don't. Later Pertronix, the 'II' and 'III' have protective circuitry and other improvements, but last I checked they are only available for negative ground. Note if you leave a points-based system in the same state you would overheat and possibly damage the coil.

I'd first double-check:

- distributor rotor: I have had one fail and there were some crappy ones going around a few years ago
- distributor cap: aftermarket are suspect--even 'Bosch'--and if the carbon plug terminal is worn or broken you could get your symptoms
- secondary wiring: you are not supposed to use stranded copper core wiring with Pertronix (supposedly, the EMI from them can damage the unit). However, I have run two Healeys with Pertronixes and stranded core for many thousands of miles; my guess is because I use resistor plug caps and resistor plugs I have been spared a fried unit. On an episode of 'Roadkill Garage,' the hosts went through several electronic ignition systems--including a Pertronix distributor--a couple alternators and a couple coils before they surmised their copper core secondary wires likely committed the crime
- the ground switch in the boot: In the 'OFF' position it cuts the circuit to the battery but also grounds the coil ground terminal (a primitive 'anti-theft' device). Check for a closed circuit at the ground coil primary next time your car won't start ('SW' or '+' or '-' depending on car's polarity). There should be two wires on it, figure out which is the one to the switch--it's usually white/black--and disconnect it.
 
I've never seen a schematic of a Pertronix--trade secret, I assume--but I think it's basically a power transistor switched by a Hall Effect sensor, and likely some timing circuitry to produce the consistent spark (which gives the somewhat improved performance). If so, it's a 'roll of the dice:' if the engine stops with the transistor forward biased and the key left in 'run' you will likely fry the transistor; if not, it might endure an overnight event. Everything I've heard about them is that, if they fail, it's permanent; i.e. they work or don't. Later Pertronix, the 'II' and 'III' have protective circuitry and other improvements, but last I checked they are only available for negative ground. Note if you leave a points-based system in the same state you would overheat and possibly damage the coil.

I'd first double-check:

- distributor rotor: I have had one fail and there were some crappy ones going around a few years ago
- distributor cap: aftermarket are suspect--even 'Bosch'--and if the carbon plug terminal is worn or broken you could get your symptoms
- secondary wiring: you are not supposed to use stranded copper core wiring with Pertronix (supposedly, the EMI from them can damage the unit). However, I have run two Healeys with Pertronixes and stranded core for many thousands of miles; my guess is because I use resistor plug caps and resistor plugs I have been spared a fried unit. On an episode of 'Roadkill Garage,' the hosts went through several electronic ignition systems--including a Pertronix distributor--a couple alternators and a couple coils before they surmised their copper core secondary wires likely committed the crime
- the ground switch in the boot: In the 'OFF' position it cuts the circuit to the battery but also grounds the coil ground terminal (a primitive 'anti-theft' device). Check for a closed circuit at the ground coil primary next time your car won't start ('SW' or '+' or '-' depending on car's polarity). There should be two wires on it, figure out which is the one to the switch--it's usually white/black--and disconnect it.
When I was troubleshooting my Pertronix the tech guy had me check for ground resistance from the distributor to the battery ground in the trunk through the Battety Shutoff switch. I immediately found an error in ground resistance! I wiggled the shutoff switch knob and my ohms changed. I bypassed the switch and my idle was improved. A Harbor Freight multimeter worked just fine for the testing.
 
Oops ... this is incorrect, my bad: "('SW' or '+' or '-' depending on car's polarity)."The terminal labeled 'CB' would be the ground (either through the boot switch or the points). 'SW' should be hot with the ignition key in the 'run' position. The coil will still work if wired backwards, but will produce a slightly weaker spark; the (best) explanation I've heard is that, properly wired, the output/spark will travel through both the primary and secondary windings, giving a slight boost to output voltage.

Coils are often suspected, and they do fail, but they have no moving parts and theoretically could last forever (both my cars, I believe, still have originals, and the BJ8 has over 210K miles on it). It's a bit ironic (to me) that modern cars with 'coil-on-plug' electronic ignitions are more prone to fail (the coils are not much bigger than a spool of thread). I think that's because there's a lot of voltage going through the secondary windings, which have to be very fine with not much dielectric (insulation). I've had numerous failures on my Lincoln LS due to (DOHC) valve cover gaskets leaking oil into the plug wells, shorting the coils. When it happens, the primary wiring creates a voltage spike which knocks the ECU 'unconscious.'
 
Thanks all for your thoughts. I'll be investigating the suggestions. A couple of new details. I installed the original coil and had 8 volts (using my Harbor Freight multimeter) with the key on. The battery checked at 12.4 volts. The car has been idle for two weeks. No spark on the spark plug with either during vigorous cranking. But I had sensed that the engine wanted to start upon turning off the ignition. With a plug grounded on the block, it does not spark on turnover but sparks just once as the ignition is switched off. We--my neighbor has enlisted--tried it a couple of times with the same result. Is this diagnostic? As it happens, I discovered years ago that my distributor is 180 degrees out and have never fixed that. The car is negative ground.
 
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