F134 runs for 5 minutes then cuts off

I just picked up a 1963 Cj5. It has a dead battery, but will start with a jump box or cables to a good battery. It then runs pretty smooth for about 5 minutes then cuts out. It will restart after a few minutes of sitting, but then dies again after a few minutes. (jumper cables disconnected after starting)

I think it is the elecrtrical system (generator looks really old, volt regulator is newer) Is it possible that when it gets warm the generator stops producing a spark? ot is the points, rotor, or coil the problem?

I have not put a meter on anything, I was just hoping that someone else has had this problem and could point me in a direction to go.

The jeep looks like it was driven pretty regular until this year, as it is not beat, and the tires and brakes are real good and fresh. Any help would be great!
I am thinking of swapping the gen for an alt, new battery, and possibly a new HEI dist...help please.:?

 

Is the coil hot after it shuts down?
If it is hot to the touch the coil has leaked the oil out and is overheating.

 

Thanks, I will check and be back in a couple hours to let you know. (still at work, but not working) hehe!

 

The coil does not get hot at all, anything else?

 

Ballest may be bad.
I'd still swap the coil out if it looks old.

 

Hot wire the coil and eliminate part of the electrical system. From the battery "+" run a wire to the coil "+". If problem persists (and it's electrical) it's coil or distributer. If the issue goes away your ignition is grounding out somewhere.

 

When it died, I checked for a spark by removing the coil lead from the cap, touching it to ground and the spark will reach about only about 3/4" long, any further from the ground point, it will be nonexistant, I plugged it back into the cap, started it, and the engine cut out after 1 minute or less.

 

is there a NAPA part # for the coil?

 

dealt with exactly this issue a few years back with my Harley - I am almost certian, it is a voltage regulator or the generator is not charging. With a generator, after removing a battery, or draining it completly, you have to "polarize it" - usually using a jumper wire from the bat to the terminals after it starts, ort it oculd be a bad generator.

What your symptoms are telling me, are the jumper cables from the jumping vehical are charging the battery enough to run the jeep it till it drains the batt.

Look closely at the charging - my money is it is not charging

 

My 55 has been converted to 12 volt by PO, the NAPA part # is IC14 but that is for use without a ballast resistor.

 

This darn near drove me insane on more than one occasion, on differant vehicals, the engine will run on just the battery when it has enough jucie, for about 5 min tells me the batery isnt fully charged when you are starting it. had a dodge dart that also did this once upon a time, there was a ceramic balist resistor in there that kept the system from charging - my pop had come to my rescue, from work - we jumped it, I thanked him and drove away - made it 5 blocks, he came back and we bought a battery, 2 days later we discovered the problem. The harley, on a full battery can run for about 3 hrs on the highway (ask me how I know and I'll post a link to a 15 page thread that lead to the motor company replacing the bike).

System is not charging IMO it may show 12 volts, your looking for amps.


Charge the battery till full, overnight. bet it runs longer than 5 min, but it won't be fixed till you find whether it is the voltage reg., generator, or if there is a bad balist resistor in the system

Get a case a beer and keep us posted, good luck

 

My money is on the coil or the ballast resistor. They're both cheap and if you walk into your local napa they should be off the shelf parts, at least they were when I replaced them on my '71.

 

Thanks for all the Tips, I will try to resolve this week and let you all know how it goes. The case a beer tip is probably the best one, although the job may be a little funny looking after the suds kick in!

I am gonna try a battery, coil, and regulator top start, afterall nothing lasts forever!