Mechanics

TRUCK WONT HOT START

Ford F-150

1987 F-150 XLT Lariat 4x4
if I turn my truck off after driving it any distance I wont be able to start it back up for up to an hour. It starts up fine after the wait. I just changed the spark plugs, timing belt, air filter, thermostat, and just bought a fuel filter. Can anyone tell me why my truck is doing this?
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Hobbsw
May 26, 2006.




Please provide the engine and mileage.
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Tiny
Losone
May 26, 2006.
The truck has the 5.0L 302 V8 and it has 280,000. It runs great and drives amazing, the only problem is the starting. I have a feeling its something electrical, but I dont know what to check.

Tiny
Hobbsw
May 28, 2006.
I don't think it is electrical. I think you have a tired engine with weak compression rings. When the engine gets hot you loose compression to the point it won't fire. (Around 75-80 lbs)

Remove all the plugs on a cold engine. Do a dry compression test and record the reading. Do a wet compression test (a tablespoon of oil in each cyl.)

The difference on a good engine should be no more than 15-20 pounds onn each cyl.

I expect your will read about 105-110 dry and about 150-160 wet. That is proof it needs rings. Good luck

Tiny
Losone
May 28, 2006.

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