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Started car and after several minutes of idling, it just quit suddenly. Several attempts produced no fire, just cranking. Checked all the usual stuff - cap, rotor, wires new and ok, fuses ok. Figured it was either coil or old Hayes magnetic distributor pickup (points replacement) then decided to go ahead and replace the old Hayes magnetic pick up for a new Pertronix unit. Also put in a new Pertronix coil. No luck. Have re-checked all connections, ground to distributor body - all ok. Checked voltage to + side of coil with other side to known ground with switch on and only read about 9 volts. No ballast resistor in the circuit - it was removed years ago when the Hayes was put in.

Thoughts go toward ignition switch - is that possibly bad. If so, do you have to drop the steering column to get to the ign. switch?

Can any one suggest next series of tests to help me find the problem.

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Panterapat, If you have a remote starter you could connect 1 remote clip to the + battery side of your solinoid (mounted on the firewall plate) then the other clip to the small connector on the solinoid closest to the battery cable. Hit the remote starter and engine should crank. This just gives power to the starter. Then try turning your key to ON (run position) and hit the remote starter (ZF in neutral) and it should fire. This would show that the key in start position cut's off the power to the coil but runs the starter. To really hot wire it don't turn the key to ON but have a small piece of wire to connect the +bat side of solinoid to the other small terminal when it fires, this keeps it running, take wire off to stop. note that I have not done this to my Pantera but used to do it to my Mustang all the time. xperts weigh-in please.

good luck
You should confirm it is spark related before going to far. Pull the plug wire that goes from the coil to the dist cap (dist cap side). Place the plug wire end against some grounded metal (engine) then try to turn the car over.

If you get a strong spark then the problem is elsewhere. This means fuel or internal machanical.

If you get no spark or the spark is weak then you confirmed you are on the right path in looking at the electrical system.

Simple test to prevent trying to solve unrelated problems.
My car was doing that last year. It would be idling and then for no reason just cut out. It was hard to start after that, and when it would start it would stall after minutes of driving it. This left me stranded one evening and I had to get it towed home. The next day I put a new coil and still nothing. I finally purchased a $10.00 after market ignition switch and installed it under the dash. Cranked right up and has been fine ever since. It's been like that for 9 months or so. I took apart the original switch and cleaned it up and plan on reinstalling it soon. Let us know what you find out.

If you have a strong spark, it could be that your dist gear rollpin has sheared. This happened to me, but at a higher RPM than idle (I was cruising along).

If you run out of things to check and want to check this, do the following:

Remove the dist cap and make a reference mark as to where the rotor is pointing. Maybe it's pointing straight back at the carb, put a piece of tape on the carb exactly where it's pointing. If it's not the rollpin, this is where you'll line the rotor back up to when you put the dist back in.

Next, make a 'slash' mark at the base of the dist and engine block with a sharpie marker. This indexes the dist to the block. If it's not the rollpin, you just line up the mark on the base of the dist with the mark on the block after you've dropped the dist back in and your timing is restored.

When the dist is out, you'll see a little circle on the dist gear. If you can see light through the circle (rollpin), the rollpin is intact. If you can't, the pin has sheared and your timing was all out of whack.

If your rollpin is good, just put the dist back in, line up the marks, tighten it down and keep looking! If it's not, carefully clamp the dist in a vice gear down and use a piece of wood and small hammer to knock the gear off. Smooth out any burrs that may be on the shaft with a file. When installing the new rollpin, DO NOT 'double up' or put a smaller rollpin inside the right sized one. DO NOT put a solid pin instead of the rollpin. Intead of the pin failing in the future, something else may have to give, like the oil pump shaft.

To install the dist, bring the #1 cylinder up to Top Dead Center on the power (spark) stroke (O degrees on the balancer). Line the rotor up to the #1 cylinder on the dist cap and tighten the cap down. Start the motor and set the timing.

I hope it's something simpler and you don't have to go through all this, but if you do it's not all that hard to do. You could have it done in an hour.

Good luck!

I would think that if the rollpin had sheared off you could check this easily by just taking the dist. cap off and cranking the engine. If the rotor turned in a constant rotation the gear is still ok. If the rotor stayed in place or just jumped then either the gear rollpin is sheared or the timing chain is worn and slipping. In either case your right the timing would be all whacked out.

I was a hour away from home when my rollpin sheared while cruising down the highway at about a constant 2500 RPM. Fortunately for me, the rollpin sheared in a way such that the gear spun about 90 degrees (quarter way around the shaft) then the piece that was in the gear lodged itself into the shaft!

The car lost power, sputtered, then shut off. I never fully tighten down my dist (although I always carry tools with me). I leave it very snug so that with a good amount of force, I can move it. After I checked spark and fuel, and both were there like they should be, I started moving the dist both ways more and more until the car finally started. At this point, the wires were at their limit (I could've moved them over a post if I needed to).

I immediately pointed my Pantera towards home and limped home. When I got home I yanked out the dist and BAM! No light through the rollpin. After I knocked the gear off was when I noticed the groove and little hill of metal caused by the rollpin lodging against it that allowed me to get home under my own power (which is always a triumphant feeling!).

So it could be feasible that the rollpin could still be the culprit.

This is all just another possible avenue if and when Panterpatt gets to the point of throwing his hands up in frustration.


You're right. If the gear was wedged with the pin every thing would have looked ok from the top. Yep, turning the dist in order to get it to fire to get home would work. I think that I'm going to loosen up the hold down bolt also. I would not like to first find it, then loosen it up on a dark road at night.

This response if from the Boss Wrench himself, Jack DeRyke:

Take this to the Bank: any time an engine quits suddenly, its likely an electrical problem -unless parts of the crank or rods are showing outside the block! So circumstances point to either a bad distributor or something in that area & requires distributor removal from the engine for final diagnosis.

#1 likely distributor problem- the infamous roll pin that attaches the drive gear to the distributor. Once the distributor is out, hold the gear up and attempt to look through the hole in the gear and roll pin. If there’s no visible path through, either the roll pin is sheared, partially sheared (which drastically retards the timing) or you have a weaker spring-pin in there. Either result requires replacing the pin with a real roll pin. This is a generic 25¢ part at any auto parts store or repair shop. As an upgrade, add a second smaller roll pin inside the first, to further strengthen the assembly. Otherwise, you will be going through this exercise again down the road, guaranteed. This included all distributors incidently, aftermarket or stock, for racing or street.

#2- assuming the pin is OK & you did the upgrade but still get no fire.
Inside the distributor is a capacitor. The wire going to it sometimes cracks at the point of juncture to the capacitor body. Cap's do not show up on VOM checks since they are open circuits but are an integral part of spark-generating.
Replace it and all the short wires inside the distributor. Sometimes after 35 years, the insulation and/or grommet that allows electricity to pass from coil to distributor will harden & crack, allowing an intermittent short that also will not show up on your VOM, so look closely at this, too.

It bothers me to hear you only have 9 volts with no ballast; you should have a full 12 or 13 volts with no resistor, so the power wiring feeding the coil is also suspect. Many electronic ignitions are inoperative without at least
10-1/2 volts. I once worked on a Pantera with no fire, that after a long search turned out to have a 3” section of wire from the voltage regulator to the coil corroded internally- the wire insulation looked OK but inside, the wire had turned to green dust from corrosion. For the purposes of a VOM it was still a ‘conductor’, but would not conduct enough volts to operate an ignition.

Further inside the electrical system, the ignition switch is certainly a possible trouble spot although I can’t think of a reasonable failure mode involving the switch that would only hold up a few volts going to the coil, and still operate the starter. And since new ignition switches are almost unavailable from any vendor in the world, I sincerely hope its not that. The column need not be dropped; once the plastic covers are removed, the ignition switch is held into the column with theft-proof shear-screws that must be drilled out for switch removal.

Hope this is of value. Roll Eyes
Here's the latest. Any thoughts would be helpful.

At the coil, only measure about 11.5 volts, key in run position - Feeding power directly from the hot side of fuse 13 (window fuse) as original run wire was trashed by previous owner.

Brand new Pertronix and Brand new coil. Wired correctly, grounded.

At ignition switch, incoming voltage at the block termination screw is also only about 11.5 volts (big pink wire feeding switch). Backside of ign. switch terminal also 11.5 volts. Battery is definately 12+ volts (new battery) and at the solenoid, 12+ volts.

Crank car, and voltage at the coil drops to 9 volts or slightly less.

When you let off, the car momentarily tries to fire and you may get one spark out the coil wire when grounded to the motor.

Where should I go next in the quest to find the problem. Should I jumper across the solenoid hot directly to the coil to see if it starts.

Tried key in the run position and jumpered across the solenoid with bump starter. Again, car turns over, not start.

thanks for anyones thoughts.
Panterapatt, 1971 thur 1972 Panteras use 1 or 2 ballast resistors, 1973 thru 1974 use a "resistance wire" that runs somewhere in the dash. I have 1972 so I don't know where exactly the wire runs, but from other BB threads that's what I remember.
You should get about 10-11 volts when the starter is turning, because the resistor or resistor wire should be shorted when the starter is engaged providing maximum voltage to the coil. This is done because of the voltage drop by the starter load. For a short time, enough to test, you can operate the coil directly from a 12 volt source just to see if the engine starts.
Hey, I had that double ballast resistor setup on a '73 Valiant years back. One resistor was for the start position and the other for run. The start resistor opened up so I would get no spark while cranking and I would only get one spark when I released the key and it went back to the run position. If you do have the double resistor, make sure that you have continuity through both the start and run sides of it.
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