Hi,

I have a 1979 Supercab that has only 86,000 miles on it. When it has been sitting overnight or all day , she starts fine. but if i run it for about 15 minutes and shut it down for 10 minutes or so, she will not turn over.it acts as if the battery is low even though it has a full charge. if i jump it , she fires right up.

I have been told that it is caused by vapor lock. but if that were the case, she would not start if jumped. At least that is my experience with vapor lock. i have also been told, the starter itself would be the problem.

I will be pulling the starter off tomorrow, but if someone has another idea I would appreciate hearing from you.

Thanks for your help.

supercabbie

 

Agree with your feeling about vapor lock, this is an electrical issue. Clean the battery cables, not on the exposed outside but remove them and scrape the inside of the terminals and the contact area of the posts. When this is done, test alternator output with voltmeter, 13.8-14.2 volts, and finally test battery. Sounds goofy but resistance is increased with temperature and thus both voltage and amperage requirements are higher with a warm engine versus a cold one.

 

I will give it a try.

thanks for the input

supercabbie

 

my 78 ranger does this also, but a couple off people told me that my choke could be sticking. i just havent had the time to do any work to my truck, so yeah any help would be awesome, it will sometimes blow out smoke out the tailpipes also, does your truck do this ?

 

Hi,

Once in a while it will belch out some white smoke on startup. Maybe once or twice a month. I want to work on it today if i can stand the heat. Close to 100 today.

supercabbie

 

i think its electrical, as stated. i had some problems similar, i replaced the Battery, Posi and Ground terminals/wires and rebuilt the alternator. Now it runs like a champ.

 

where in florida are you, im in zephyrhills