318 running like a top, then just stopped

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RJG

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Well, my '64 Signet, with a 318 has been running beautifully. Until yesterday. After about 10 minutes of driving, while ideling at a stop, the motor just stopped (just as if the key were turned off). It wouldn't start again immediately. But, about 15 minutes later, it started normally and ran smoothly for about 20-or 30 seconds. Then it simply stopped again.
That was all, it hasn't started since. Getting plenty of fuel, other electronics are fine, cranks over fine, but not even a suggestion of wanting to start. I assume it is the spark, but thought someone might have a suggestion as to which electronic part to check first.
Thank you FABO for any input you offer.
 
coil, ballast, points if you are still using them or ECU for electronic ignition.
 
RJG said:
Well, my '64 Signet, with a 318 has been running beautifully. Until yesterday. After about 10 minutes of driving, while ideling at a stop, the motor just stopped (just as if the key were turned off). It wouldn't start again immediately. But, about 15 minutes later, it started normally and ran smoothly for about 20-or 30 seconds. Then it simply stopped again.
That was all, it hasn't started since. Getting plenty of fuel, other electronics are fine, cranks over fine, but not even a suggestion of wanting to start. I assume it is the spark, but thought someone might have a suggestion as to which electronic part to check first.
Thank you FABO for any input you offer.
Click to expand...

Check the capacitor (on swedish "kondensator").
 
I suggest ballast resister first. Cheap, and the about the easiest to change, and have been known to go out.
 
When my car did that it was a bad coil. I also had a problem with a ballast resister that was similar to that. the car heats up and gets real hot under the hood and then those electrical componets don't work properly.
 
RJG said:
Well, my '64 Signet, with a 318 has been running beautifully. Until yesterday. After about 10 minutes of driving, while ideling at a stop, the motor just stopped (just as if the key were turned off). It wouldn't start again immediately. But, about 15 minutes later, it started normally and ran smoothly for about 20-or 30 seconds. Then it simply stopped again.
That was all, it hasn't started since. Getting plenty of fuel, other electronics are fine, cranks over fine, but not even a suggestion of wanting to start. I assume it is the spark, but thought someone might have a suggestion as to which electronic part to check first.
Thank you FABO for any input you offer.
Click to expand...
Well found no spark coming off coil. But tried different coil, still no spark. The multi-meter suggests the ballast is good (upper connections and lower connections each showing contact).
 
RJG said:
Well found no spark coming off coil. But tried different coil, still no spark. The multi-meter suggests the ballast is good (upper connections and lower connections each showing contact).
Click to expand...
Also,
there are two electronic boxes on this car. One on the fire-wall near distributor(has larger connection boot), and the other on the inner fender well (two pin connection on that one). Not sure which is ECU , or what the other one is.
 
Sounds like it's been converted, 2 pin should be the voltage regulator, the other ECM, Pretty common way for them to fail. Knock off hot, restart cold a few times before they completely fail.
 
What is it? A Chevy engine?
 
replace the part that just broke and then next time fix the part that broke that time and then the next part that broke or just get new parts.
 
Yeah but I've seen too many times people change the ecu, the coil, cap and rotor, the wires, etc when it's really something simpler like a damn vacuum leak, a wide reluctor gap, bad wiring connection/ground. Troubleshooting SAVES money in your wallet.
 
Yeah I've seen to many times where people have changed the weak link just to make that new strong link create problems for all the other weak links. The whole entire ignition system can be given replacement pieces for probably $200 or so. Anyways it sounds electrical....
Or you could do like a lot of people do change the ballast resistor today and it runs again and then two weeks later you broke down again because the distributor went out and then two weeks later you're broke down because the coil and out and then 2 weeks later you break down because the voltage regulator went out and then 2 weeks later you broke down because.....
then again the break booster vacuum line could have fell off? Who knows?
 
GeorgeH said:
Sounds like it's been converted, 2 pin should be the voltage regulator, the other ECM, Pretty common way for them to fail. Knock off hot, restart cold a few times before they completely fail.
Click to expand...
Yes, the other is the voltage regulator. Thank you for the input. When you say it is a common way to fail are you refering to the ECM. I am under the impression that the voltage regulator shouldn't interfer with spark from coil, or keep the car from starting. Is that incorrect? Not sure how to test.
 
RJG said:
Well found no spark coming off coil. But tried different coil, still no spark. The multi-meter suggests the ballast is good (upper connections and lower connections each showing contact).
Click to expand...
No need to work with suggestions, and it will be misleading if you just check for voltage being at each end of the ballast with the ignition switch in the ON position.

Put the meter in resistance mode, at the lowest scale, then cross the wires and take resistance readings a few times and note the average; this is the resistance of the leads alone. Then disconnect the wires from the ballast and check the resistance through the ballast. Subtract the lead resistance and you will have your ballast resistance. Cold, a stock Mopar ballast will be in the 0.5 to 0.7 ohm range. (VERY low, which is why you need to subtract the lead resistance to get an accurate number.)

If the ballast is good, you can then test for a good coil and wiring without the ECM and distributor. Disconnect the ECM, set up a wire jumper so one end is grounded and can reach the coil - terminal, and disconnect the distributor end of the spark wire from the coil and set it 1/4" from ground. Turn the key to ON, and then momentarily ground the coil - for a fraction of a second with the wire jumper and then unground it. Each time you unground it, you will get a spark. (Be careful.... if you are touching the end of the wire when you unground it from the coil, YOU may get a nice little shock!) The sparks you get should be good hot, blue sparks.

Then use your multimeter in resistance mode to measure the reluctor resistance through the 2 prong connector going into the distributor; do this while this distributor is disconnected. If it is good it will read a few hundred ohms. This is not a guaranteed test but is usually a good indication of health of the reluctor. Then set the gap from the reluctor to the rotor teeth to around .008" with a non-steel feeler gauge. Brass will do, or 3 thicknesses of standard lightweight printer/copy paper can be used in a pinch to get close to .008".

If all the above are good, then replace the ECM. A NOS OEM is best; the new ones made overseas have earned a poor reputation for reliability. If the ballast is bad, then find one that is RIGHT (not just any ballast), or ignition performance WILL suffer; the Mopar ballast resistance is unusually low. The MSD 0.8 ohm ballast is the closest I have found to the stock 0.6 ohm (cold) Mopar ballast resistance. A BWD RU19 is the best 'box parts store' type and is so-so for spark performance. (I usually go on eBay and find a NOS Mopar ballast.)
 
RJG said:
Yes, the other is the voltage regulator. Thank you for the input. When you say it is a common way to fail are you refering to the ECM. I am under the impression that the voltage regulator shouldn't interfer with spark from coil, or keep the car from starting. Is that incorrect? Not sure how to test.
Click to expand...
The VR would not normally fail in a way that would interfere with starting or running. The whole charging system operation can be quickly checked with the car running: the battery voltage should be in the high 13 to low 14 volt range when running at a fast idle. But of course, you need to get the car running first. Your symptoms don't point to a charging system problem.
 
BTW, we are all assuming you have the later Mopar ignition system with the ECM and a 2 lead wire from the distributor to the harness to the ECM. That ECM will have 4 or 5 connection pins in a 'sorta' penta pattern. Is this correct? (It is non-standard for a '64 but so is a 318.... unless it is a 318 Poly engine.....) A simple 1 lead wire from the distributor to the the coil - terminal would be standard for a '64.

If you do have an ECM, make sure you remove the mounting screws and clean the ECM case and fender to make sure it is grounded properly to the chassis.
 
nm9stheham said:
No need to work with suggestions, and it will be misleading if you just check for voltage being at each end of the ballast with the ignition switch in the ON position.

Put the meter in resistance mode, at the lowest scale, then cross the wires and take resistance readings a few times and note the average; this is the resistance of the leads alone. Then disconnect the wires from the ballast and check the resistance through the ballast. Subtract the lead resistance and you will have your ballast resistance. Cold, a stock Mopar ballast will be in the 0.5 to 0.7 ohm range. (VERY low, which is why you need to subtract the lead resistance to get an accurate number.)

If the ballast is good, you can then test for a good coil and wiring without the ECM and distributor. Disconnect the ECM, set up a wire jumper so one end is grounded and can reach the coil - terminal, and disconnect the distributor end of the spark wire from the coil and set it 1/4" from ground. Turn the key to ON, and then momentarily ground the coil - for a fraction of a second with the wire jumper and then unground it. Each time you unground it, you will get a spark. (Be careful.... if you are touching the end of the wire when you unground it from the coil, YOU may get a nice little shock!) The sparks you get should be good hot, blue sparks.

Then use your multimeter in resistance mode to measure the reluctor resistance through the 2 prong connector going into the distributor; do this while this distributor is disconnected. If it is good it will read a few hundred ohms. This is not a guaranteed test but is usually a good indication of health of the reluctor. Then set the gap from the reluctor to the rotor teeth to around .008" with a non-steel feeler gauge. Brass will do, or 3 thicknesses of standard lightweight printer/copy paper can be used in a pinch to get close to .008".

If all the above are good, then replace the ECM. A NOS OEM is best; the new ones made overseas have earned a poor reputation for reliability. If the ballast is bad, then find one that is RIGHT (not just any ballast), or ignition performance WILL suffer; the Mopar ballast resistance is unusually low. The MSD 0.8 ohm ballast is the closest I have found to the stock 0.6 ohm (cold) Mopar ballast resistance. A BWD RU19 is the best 'box parts store' type and is so-so for spark performance. (I usually go on eBay and find a NOS Mopar ballast.)
Click to expand...

Wow, Thank you for all the info. Regarding the ballast: I wasn't aware that the ballast could fail if it had connectivity. I simply disconnected the wires and checked for connectivity between terminals. I assumed a bad ballast would show an open circuit. I will check for specific resistance.
Found no spark from coil. I had spare coil, and switched it out. Still no spark from coil. So seems most likely ECM or ballast.
Thank you again.
 
nm9stheham said:
BTW, we are all assuming you have the later Mopar ignition system with the ECM and a 2 lead wire from the distributor to the harness to the ECM. That ECM will have 4 or 5 connection pins in a 'sorta' penta pattern. Is this correct? (It is non-standard for a '64 but so is a 318.... unless it is a 318 Poly engine.....) A simple 1 lead wire from the distributor to the the coil - terminal would be standard for a '64.

If you do have an ECM, make sure you remove the mounting screws and clean the ECM case and fender to make sure it is grounded properly to the chassis.
Click to expand...
Yes, It has been converted. Unfortunately ECM is in very difficult location, on fire-wall
 
RJG said:
the motor just stopped (just as if the key were turned off). It wouldn't start again immediately. But, about 15 minutes later, it started normally and ran smoothly for about 20-or 30 seconds. Then it simply stopped again.
That was all, it hasn't started since.
Click to expand...

I would also look at the "air gap" in the distributor. This is the gap between the reluctor and the pickup coil. It should be .008 checked with a BRASS feeler gauge. It's possible the pickup coil has gone bad as well.
 
You can run a jumper straight from the battery plus terminal to the coil plus terminal and bypass all the harness wiring. For troubleshooting purposes this will be fine. Every time you start the engine with a cold ballast, the coil will receive a very similar voltage, so don't concern yourself with this jumper doing any damage. It will take thousands of miles to hurt that coil.

Make sure the ECU is well grounded back to the battery,follow the path back. This is a really simple ignition system to troubleshoot, and they normally run trouble free, except possibly for replacement ballasts. The original equipment ballasts lasted hundreds of thousands of miles. You can sub in almost any ECU from any Mopar, for test purposes, the only caveat being the ground return;all ECUs have to be grounded back to the battery.
On the other hand, the dizzy does not need to be grounded.You can take it out,still plugged in. With the coil wire Near-Grounded, and with the key on, you can spin that driveshaft and watch the light show at the coilwire.
If no light show, turn the key off while watching the coil wire. It should spark one time. It should do this every time the key is cycled from on to off.This proves that the coil and ballast are working, and also that the ECU is alive. With no stream, tho, you will have to check over the pick-up. They will fire the coil with any reluctor gap from zero(rubbing) to about .030. The spec has been mentioned. I run .011 cuz I have a brass-feeler that size.
If you have a loose pick-up and want to test it, plug it in, turn on the key, and pass any iron containing item over the armature. it will spark one time every time you pass by it. Touching it is ok and will not affect the one spark output. To install it, you first need to make sure the colors of the leads match those of the one you are replacing, and that the colors match the harness, and that when plugged in the colors line up;orange to orange and black to black,usually.
 
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For me, I like to carry a spare ballast resistor in the glove box anyways. For 5 - 10 bucks, I'd buy a new one, take the 33 seconds to install it, and if it's not the problem, you'll have a spare to carry in your glove box.
ECU's are a whopping 14 bucks shipped to your door, throw one of them in your car as well. Next time you loose spark, you'll have a couple of key components to try.
LX101 Ignition Control Module for 72-89 CHRYSLER DODGE PLYMOUTH 3438850 3874020
 
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