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TR6 TR6 died/ won't start

j3k5d4

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2 weeks ago I had been driving my 1974 TR6 for about 70 miles and it died out shortly after leaving a stop light, about a mile from my house. The car just died out with no warning, and was not running rough or showing any other signs. I checked the fuel and the spark and discovered the fuel was flowing fine, but the spark was not. I am getting spark from the coil, but not at the plugs. I replaced the distributor cap, and the rotor and ignition wires all look fine. The previous owner did install a Pertronix igniter, but it does not appear burnt out. The rotor is rotating when I try to crank the car, but I am unable to get a spark at the plugs. Does a coil send out a continual charge, or is it pulsed and is mine just off time somehow? I am stumped on this one, because it is at the limit of my knowledge on the electrical side of the car.
 
Check the igniter. As the distributor rotates it sends spark to the plugs. Make sure coil wires are tight, see if coil is warm/hot. If hot, replace, but check with Pertronix for troubleshooting the system.
 
The spark from the coil is "pulsed" or distributed to the wires' contacts in the cap by the rotating rotor.
The Pertronix Ignitor is supposed to create the "pulse". You set the timing though. Did you find the distributor loose ?
 
The distributor isn't loose, but would the timing go out so quickly while driving?
It hadn't happened to me, but I seem to recall reading that it has happened.
I guess it would have depended upon on how much the distributor rotated away from the sweet spot.
 
2 I am getting spark from the coil, but not at the plugs. I replaced the distributor cap, and the rotor and ignition wires all look fine.

Others may be inclined to "stampede to the clitoris" (assuming the Ignitor has failed), but having been there, I'm inclined to look for an easier approach. Replacement rotors may look fine, and perhaps be very new, but that does not preclude a non visible fracture allowing a high voltage spark to be grounded out by the shaft it sits upon. Your failure mode is in perfect alignment with what happened to my 74 TR6 on more than one occasion. I'd start with a new rotor. Actually, being the inquisitive type, I'd start with a spark plug resting on the valve cover on the end of a wire plugged into the coil. When the engine is turned over, it should spark. Then I'd replace the coil wire to the distributor, put the plug on the end of any given wire, rest the plug on the cover, and check for 1/6 as many sparks while turning the engine over.

In any case, if you have spark at the coil, but not at the plugs, the problem is after the Ignitor and doubtfully timing related. Of course anything is possible and the timing chain may have jumped a tooth or seven, or the flow of electricity may have abandoned normal conventions.

It is probably a simpler solution than you think.
 
Engine was running well, then suddenly stopped.

Fuel flow ok.

I'm betting a broken wire, bad coil, or bad condenser.

Please let us know what you find!
Tom M.
 
Try Texas' test of running a spark plug wire directly from the coil's center terminal to a plug resting on the valve cover. A spark while cranking will verify the Ignitor is working.

That said... the TR6 wiring diagram at Advance Auto Wire web site says the '74 came from the factory with a ballast ignition system. If the previous owner did not change the factory wiring and ran the Pertronix red wire directly to coil (+) for power, a break in the white/pink wire would allow you to have a spark on cranking but the engine would die as soon as you released the key. A break in the white/pink wire (or failure of the ignition switch) while driving would immediately stop the engine.

Where are the ignitor module wires connected and what color are the wires are on the coil terminals?
 
On a unmolested 74, the resistor (ballast) wire is embedded in the wiring harness, solid (not stranded) and becomes frail over time. It can easily be broken and could be the issue as well. I think the Ignitor should be installed on a switched source (not powered by the reduced voltage from the ballast wire). Measuring the voltage supplied to the Ignitor with the key on would be a good test too.

Sorry if my reference to Monty Python' Meaning of Life regarding starting with the easy stuff first, was lost. It's a classic Cleese line rarely be repeated.
 
Just an update to the guys that have helped, I was able to run the test on the igniter from ehow, and it would bounce between about 200 mV and the full 12V, so the igniter should be good. Im having to wait for the rotor to show up tomorrow morning because my parts shop didn't have one in stock. All the wires are on tight, and when i run my spark plug directly from the coil I get a spark as well. Hopefully by tomorrow evening with the new rotor I can let you know what the actual fault was.
 
dklawson: I believe he had changed the factory wiring some (don't have an straight answer on that). When I took possession of the car it did not have the white/pink wire running on it, and he had run and been cranked multiple times since then (if that makes a difference). The ignitor module has a red and black wire connected directly to the coil's pos. and neg. post.
 
What other wire or wires do you have on the coil's positive terminal ?
 
The only other wire on the terminal is a a faded yellow/ white (can't quite tell for sure the exact color, but it could easily be a combo of the two) wire that runs into the wire harness. Based on the wire diagrams I assume it runs to the starter relay or the fuse box. I have seen 2 different wire diagrams for the 74 year model (Advance Auto website and Robert Bentley Guide Book).
 
The only other wire on the terminal is a a faded yellow/ white (can't quite tell for sure the exact color, but it could easily be a combo of the two)

The only other wire on coil (+) is white/yellow? If you turn the key to the run position (not start), do you measure 12V between coil (+) and ground?

As you observed, the white/yellow goes from coil (+) to a switched output terminal on the starter solenoid. If the white/yellow is still connected to the starter solenoid, there should be an additional wire on coil (+). Are there any loose wires near the coil?
 
You'd have seen it if there had been a ballast resistor wire. It would have been conjoined in the same female connector on the coil as the white/yellow wire. That should address "Texasknucklehead's" concern.
 
I am getting spark from the coil, but not at the plugs.

I just had this happen to me after pulling my car out of storage. I got it to idle and then it stopped and wouldn't restart. It was the rotor. It took an embarrassingly long while for me to figure it out.

The rotor that went bad looked perfectly fine. It wasn't burned on the end that points to the caps and there were no visible cracks.

One other thing to check, if you haven't, is that the graphite rod in the middle of the cap is in good condition. I had one fall out on me once. That also took a while to figure out.
 
If this happened (sudden, complete nada) the first thing my wife would ask is "Did you check that little wire to the distributor that likes to break?'.

Possibly a white/black wire -- I don't know TR6s or what Pertronix does to wiring -- but on my TRs that wire can break internally and look okay but eliminate any chance of ignition.

A simple jumper wire from the coil (-) to the distributor can check this.
 
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