Car won't start suspect it's in ignition

[krazykuda]

I'm trying to help another member get his car going again, it won't start.

It has a mallory distributor and msd coil.

It seems like it's not getting spark all the time, but only after you stop cranking, it sputters.

We tried to check for spark by putting a spare plug on the end of a spark plug wire and holding it to ground, and it's not sparking during cranking, only when we let off.

We seem to be getting weak spark out of the coil.

Here's the car:

View attachment Eddie Dart A05 B.jpg

View attachment Eddie Dart A08 B.jpg

We're getting 12.465 static volts across the battery. Here's the ballast resistor, it has 10.28 coming in and 3.08 coming out:

View attachment Eddie Dart A14 B.jpg

On the coil here, we're getting 2.93 on the positive side, and 2.05 on the negative side with .87 across them.

The stock coils that I have checked usually are around 6 volts, this seems kind of low. How do we isolate where the problem is?

View attachment Eddie Dart A17 B.jpg

Here's the distributor:

View attachment Eddie Dart A15 B.jpg

 

[67Dart273]

This sounds like the proverbial IGN1 / IGN2 or ballast resistor problem

I'd do one or two things............

Leave the key in run long enough to confirm the ignition is getting power. See if you have spark by jumpering the start relay, which will "work around" an IGN2 problem

Make sure you DO have voltage while cranking. Might be a bad ignition switch, the switch connector, or bulkhead terminal where the brown IGN2 wire comes through

I'm assuming it DID run with this same setup?

 

[RustyRatRod]

I was gonna say bad ballast, but the master has beaten me to it. lol

 

[krazykuda]

This sounds like the proverbial IGN1 / IGN2 or ballast resistor problem

I'd do one or two things............

Leave the key in run long enough to confirm the ignition is getting power. See if you have spark by jumpering the start relay, which will "work around" an IGN2 problem

Make sure you DO have voltage while cranking. Might be a bad ignition switch, the switch connector, or bulkhead terminal where the brown IGN2 wire comes through

I'm assuming it DID run with this same setup?

Yes, it did run.


Then just before I went over, he started it and it ran for a short time, then quit. It would not restart.

A day or two later it would start cold, then quit after about 5 minutes.

Then the day I went over, it wouldn't start at all.

It seemed like when we went from start/crank position to run, that's when it started to spark, but not when it cranked...

How do I check voltage while cranking? just check across the battery, ballast, or coil???

I will try the jumper across the starter relay next time I get over there, may take a week as traffic by him is bad.... :banghead: :banghead: :banghead:

thanks guys...

 

[krazykuda]

Is there a special ballast resistor for the mallory dist and msd coil, or can he just use a stock electronic ignition ballast to replace it???

 

[ScampMike]

you know what it kinda sounds like - the distributor is loose and you've gone out of timing.. though that wouldn't explain the spark issue would it..

 

[krazykuda]

you know what it kinda sounds like - the distributor is loose and you've gone out of timing.. though that wouldn't explain the spark issue would it..

It doesn't hurt to check... #-o

 

[KitCarlson]

Your ballast is OK. 10V going into ballast, there is a 2V drop between battery, likely at bulk head connector or switch. It may also be possible that the battery is down a cell when cranking. Check battery voltage while cranking.

Also check plugs, if it was running poopy due to choke pull-off failure, the plugs may be glazed.

 

[dano]

What version of Mallory distributor as in Magnetic or Optical pick up?

Did it run before or is this a new install?

Mallory does have their own resistor. I'd find out what distributor and verify wiring. If optical, follow Mallory directions on testing it.

 

[TrailBeast]

That coil is supposed to run a ballast resistor?

Have you tried jumping the coil straight from the batter and see what it does?

 

[67Dart273]

Your ballast is OK. 10V going into ballast, there is a 2V drop between battery, likely at bulk head connector or switch. It may also be possible that the battery is down a cell when cranking. Check battery voltage while cranking.

Also check plugs, if it was running poopy due to choke pull-off failure, the plugs may be glazed.

^^THIS^^ If the voltage is that low with key "in run" then the problem is in connections / bulkhead / ignition switch / switch connector.

I would look up the coil and system at Mallory / MSD. SOME Mallory coils require TWO ballasts---the old one in series with the new one.

 

[KitCarlson]

That coil is supposed to run a ballast resistor?

Have you tried jumping the coil straight from the batter and see what it does?

I looked up the coil, the primary resistance is 0.02 Ohms. That seems low, perhaps, 0.2 Ohms would be realistic. Hooking up to the battery could be a disaster (hundreds of amps ), if the distributor does not limit the current. It would be nice to know the distributor part #, to check the specs on it.

 

[xLURKxDOGx]

I had this same problem 2 weeks ago, would run for a minute then stop, turns out it was the coil.


Jake