68 jeepster wont run! need help!

[Jeep Thing]

My 68 Jeepster will start right up and run for about 30-45 seconds then it will cough, sputter and sometimes backfire then quit. It will then refuse to start again for hrs. at which time it start right up and die again.

It has a new timing chain 2000 miles, new distributer, and rebuilt carb less than 1000 miles since the distributer and carb. were done.

I checked for vacume leaks around the hoses and base of carb and found none. Even took the carb back to the rebuilder to have it rechecked. They opened it up and checked it out and everything was OK. It got a new fuel filter when the carb was rebuilt but checked it anyway and it seems good. I am running it with an electric fuel pump.

She was running and was being used as my daily driver when this all started. I had was stopped at a light and when I started through the intersection cough, cough sputter, backfired then died.

So! I don't think the problem is fuel related. I haven't been able to check the timing since I can't get it to run long enough. The distributer is tight and I don't think it has moved since it was installed. I wouldn't think it would start at all if the timing were that bad.

I know the engine is tired and has a weak cylinder. There only 35,000 miles on the odometer with years of records to support it but it has probably has 30years and thousands of hrs. just idling. The original owner use her to tow his sprayer and work around his avocado ranch.

Does anyone have an Idea what else I should check?

What is really confusing me is that it will start right up, run fairly smooth for 30 seconds or so then die.

Thanks in advance for any help.

Probably should have mentioned that it has the 225 oddfire engine.

[mike40]

If you have the older point type ignition ya might try to change the coil , I have had an intermintent short in one before that did the same thing on a small block chevy , good luck. Mike.

[Jeep Thing]

Thanks Mike
I'll give it a try.
Kirby