91 F350 Hard To Start When Hot

[Beast12]

We have a 1991 F-350 with a 5.8L V8 with automatic transmission at work. It will usually start fine when it is cold but after it has been running for a bit and you go to restart it it will crank slowly, almost like a dead battery.

Here is a list of things I have checked:

* Battery is fine. I swapped with another good battery and there was no difference. Also, the voltage drop is only down to about 10 volts when trying to start.

* All cables are fine. Played around with booster cables and it still did it.

* Replaced the starter twice with 2 different ones (from different stores)

* No binding from alternator, smog pump, etc. Unhooked the serpentine belt to see.

* Solenoid is fine. Bypassed it when checking cables.

So, what else do I need to check? Truck runs perfect after it starts. It has about 200,000 MILES on it.

-Matt

[86F150302]

I have the same problem and I was told my starter gets too hot from my headers being right next to it. Do you have long tube headers? Probably need a heat shield or something for your starter.

[northern 7.3]

i had a similar problem, the nose cone of the starter cracked and when it got hot and the aluminum expanded it made the impeller of the starter rub against the side of the nose cone. found a junkyard starter for 10 bucks, problem solved. the crack was pretty easy to see.

[Lazy K]

The next time it happens I would connect a set of jumper cables to it with the pos. connected to the batt. terminal on the fender mounted relay and the neg. connected to a good ground on the engine. See if it improves things. I would also check my ign. timing.

[Beast12]

Some people need to read my post again.

The truck does not have headers. It is a work truck. I have kind of thought about the timing.

-Matt