I think it’s the Ballast resistor?

[commando1]

After cooling off for about 5-10 minutes it started and ran for a while

You need to concentrate on this clue.

 

[HWYCRZR]

Never use emery cloth on any electric contacts, only use a clean file on points.
Only use flint paper on armatures or alternator slip rings.

What is the theory behind this? Right or wrong I grew up using emory cloth (extra fine). I don’t think I ever saw a points file until I was in college. Is it the particles it leaves behind or something else?
Thanks.

 

[HWYCRZR]

You need to concentrate on this clue.

I had a motorcycle once that the points were adjusted too close. When it got warm the gap would close and start missing. Adjusted the points and went on my way. Coil is checking out per spec when cooled off. I want to get it warm again and check.
My ignition wire had a hardened wire by the ballast resistor connector from day’s gone by, so clipped it back and put a new connector on to take it out of the equation.

 

[68PK21 440.6bbl]

The abrasive in emery cloth is non-conductive and always leaves small microscopic molecules, particles (what'eva) embedded in the contact surface which will cause arcing and will lead to burning of the contact surface and shortness of it's longevity.
Flint paper abrasive is conductive.
Files do not leave anything in the surface.
This is all from what I learned back in the 60's.

But then one of the first shops I worked in as a mechanic the old'Rum'e mechanic educated me to emery paper every new set of point's that I put in to take off "the protective coating" that the factory installed..... Ummmmm yea it's called Tungsten, it's put there to make the points last longer. In later years I did get him to admit that he did that to make sure it came back within a year for another tune up.

.

 

[rapidtrans]

You need to concentrate on this clue.

I agree.
Like maybe a bad coil?
The first sign is that cutting-out or bog he described after heating-up. Car cools down and it starts up fine until engine warms up again.

FWIW. I’ve never had a ballast resister go bad on my cars or any of Dad’s company cars going back to his first in ‘62. Granted he got new cars every year and mine were kept three years at the longest. I do recall however sometime in the 60s Dad carying a spare resister in the glove box if the car doesn’t start. Apparently a certain model (I’m thinking A bodies) was susceptible to ballast resister failure due to the placement on the firewall allowing rainwater damage. He showed us kids how to just plug in the replacement bypassing the old one in case we got stranded with Mom somewhere.

 

[polara71]

I agree.
Like maybe a bad coil?
The first sign is that cutting-out or bog he described after heating-up. Car cools down and it starts up fine until engine warms up again.

FWIW. I’ve never had a ballast resister go bad on my cars or any of Dad’s company cars going back to his first in ‘62. Granted he got new cars every year and mine were kept three years at the longest. I do recall however sometime in the 60s Dad carying a spare resister in the glove box if the car doesn’t start. Apparently a certain model (I’m thinking A bodies) was susceptible to ballast resister failure due to the placement on the firewall allowing rainwater damage. He showed us kids how to just plug in the replacement bypassing the old one in case we got stranded with Mom somewhere.

I agree with the coil but I would have been throwing a dart to hit that answer which is why I didn't say anything.
I too never had a ballast resistor go bad until a few years ago. The Walgreens alarm story was part of a series of events. Eventually leading to the car not running unless I held the key on. Thank God for FURYGT claiming B R or I would have changed out the ignition switch on the Carlisle show field.

 

[68PK21 440.6bbl]

I had a motorcycle once that the points were adjusted too close. When it got warm the gap would close and start missing.

The old early Honda 4 cyl motorcycles had the points running right off the crankshaft end.
So if you wound the engine tight all the time like 10/12k rpm the points rubbing block would wear down right quick. Then you would lose the redline, kind of a early rev-limiter built in I guess.
I remember when I use to want to take my Honda 750 with a 836 kit in it out for a Sunday blast. I'd look at it and think should I adjust the points or swap out the slipping clutch, easy, points are easier and guaranteed top rev's. Clutch only slips off the line.

Rode my girlfriends Honda 400 4 cyl once, couldn't get it to 10.5k redline, we gotta do sum'tin 'bout this, adjusted the points... Bingo. Then she comes back from visiting her mother and says she got a speeding ticket for 80 mph. I looked at her and said "And how is that my fault?"

 

[HWYCRZR]

Both my new, (current coil). And my old coil measure the same resistance on the primary circuit. On the secondary circuit my new coil is just a little higher than spec, and my old one is right on.
I ran a little more and when it started cutting out I switched coils. It really didn’t make a difference.
Resistance between the BR and coil is around .2 ohms, so I have a good circuit.
What I did notice when measuring voltage at the coil + while running it was right around 11 V. As soon as it started to miss, my voltage meter would drop down to 10.5 volts with every miss. Current draw is within spec @1.9 amps when idling, so my connections and wires from IGN (dk blue) through the BR to the coil is good. At key on engine stopped it is at 3.4 amps, just a little higher than the spec of 3.0 amps. Thinking...........

 

[413]

Did you try changing the coil wire? Like the spark plug wire?

Also run a jumper wire to the ballast resistor single wire side. This normally has battery voltage there in run position. This will supply known good constant battery voltage and bypass the ignition switch and all the connections through the bulkhead connector.

Notice: The car will not turn off with the key with this jumper wire there.

Do one change at a time.

 

[halifaxhops]

Uhm Define new point and condenser New stuff has a weak spring pressure and half the time the condenser short out or open whn they get hot. Hit it with a hair dryer when it stars then duplicate it with the cap back on. My $.02

 

[3175375]

Did you try changing the coil wire? Like the spark plug wire?

Also run a jumper wire to the ballast resistor single wire side. This normally has battery voltage there in run position. This will supply known good constant battery voltage and bypass the ignition switch and all the connections through the bulkhead connector.

Notice: The car will not turn off with the key with this jumper wire there.

Do one change at a time.

Fuel / carburetion?

 

[HWYCRZR]

Ignition circuit. Power from battery connected to starter relay. Red wire from starter relay to fusible link. (Fusible link is a year old, all other electronics working fine when engine starts missing.). Fusible link to terminal J on firewall. Terminal J inside firewall exits with 12g red wire to ammeter. Goes through ammeter coming out with a black wire. Black wire splits into 4 different circuits. One red going up to ignition switch. When key is on it feeds the ignition circuit with the dk blue ignition wire going to terminal N on bulkhead and splitting at the ignition terminal on voltage regulator and continues to BR. Goes through BR and to + terminal on coil.
I have a question on the next post.

 

[halifaxhops]

 

[HWYCRZR]

Question from above.
Does the the voltage regulator on the ignition side have any control over voltage? My thought is no.
It is only the signal wire to energize the VR. It is the field wire controlling the alternator output, so should not come into play.

 

[HWYCRZR]

Fuel / carburetion?

Seems too intermittent with backfiring to be fuel. And why wait until it is 10 miles down the road? However I did not have this issue with my last tank of gas. The gauge was on full when this started. I am down to about 1/2 now.

 

[HWYCRZR]

Did you try changing the coil wire? Like the spark plug wire?

Also run a jumper wire to the ballast resistor single wire side. This normally has battery voltage there in run position. This will supply known good constant battery voltage and bypass the ignition switch and all the connections through the bulkhead connector.

Notice: The car will not turn off with the key with this jumper wire there.

Do one change at a time.

Ok will try direct battery voltage to ign input to BR when it starts sputtering to take out the key switch.

Coil and SP wires are fairly new. I used my handy dandy champion firing indicator pen and have good spark through the coil wire and to the plugs. You can see the flash going intermittent when it starts missing. Otherwise the coil wire when running properly is almost a steady light.

 

[HWYCRZR]

It has been a while since we had a good troubleshooting thread.

As I am starting to get a lot of help, I am going to plot out my course of action.

Starting easy and non invasive.

1. reinstall coil that I was originally running when this started. (My old original did not fix the problem)
2. Bypass my key switch to see if I can rule the switch out. ( easy step) @413

3. If still an issue, heat cycle my points and condenser. per @halifaxhops

 

[HWYCRZR]

Coil installed, by passed switch.
It is not the switch.
Now it doesn’t wait to get hot. It started doing it almost immediately.

1&2 complete. I can now focus from the coil to the distributor. The coil checks out cold. Didn’t run long enough to get hot.

I have a new set of points and condenser from @halifaxhops. Will throw them in and see what happens.

 

[68PK21 440.6bbl]

Cracked distributor cap...

 

[polara71]