Starter trouble

I'm having a hard time starting my truck immediately after shutting off the engine when its hot (after a aprox. 20 min drive). It cranks over like the battery is dead. If I wait and let it cool for 15 minutes or more, it cranks ok and starts right up.

The battery and starter have both recently been replaced. The battery is charged and the alternator works. I'm curious if a hot starter is at all weaker? Has anyone had this trouble before? I've cleaned the contacts, should I be chasing a ground problem instead? Its just that when the engine is cold or only somewhat warm, it cranks over perfect.

Thanks

I've had similar problmes on past Fords. Once it was the starter solenoid and the other time it was the rebuilt starter which when swapped for a different one solved the problem.

What year is your ford? Do you have a distributor mounted TFI unit? Those are notorious for going bad. High heat causes them to malfunction and they are located next to manifold so that may be the cause. Especially if it starts after it has had a chance to cool. It's pretty easy to have checked. Take it to local napa/schucks. If it reads good and they hand it to you hot, ask them to recheck it while it's hot if they didn't already. Best of luck.

Thanks for the suggestions. It's an 86 with TFI on the Distributor. I've already had the TFI checked out two separate times and it tests ok hot. The only way I see the TFI screwing it up is if a hot (and faulty) TFI could inadvertently advance the timing forcing the plugs to fire against the starter. That's really how it seems to turn over... it feels like a dead battery, yet cranks over perfect if I wait long enough for it to cool. The rebuilt starter should still under warranty, so I might end up checking that out.

yo, My attention span is zilch today so bear w/me please...Since it is running ok UNTIL it is shut down and it is restarted hot; I GUESS that the alt is ok and the starter may be ok since it is A Ok when cold so let's try your guess on the ground(s); "Engine cranks slowly and the battery and starter both test okay. Check the battery ground cable attachment at the engine (most cases the cable goes to the frame rail, and a second cable runs to the block.) The ground cable apperently was made too short causing it to rip out of the attachment eyelet as the engine rolls during acceleration. If you find this problem, replace the cable with a longer one.

NOTE: If a wiper motor problem or failure should occur around the same time this problem came up, it is advisable to check the wiper motor ground wire because this circuit will act as a backup for the damaged battery cable. It could likely be burnt and also need replaced."
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more:
http://www.genco1.com/newsletter_details.cfm?id=78
Problems with the negative battery cable is a major cause of starting problems in Ford, Lincoln, and Mercury vehicles. Bad battery cables can cause slow cranking or a grinding noise when trying to start an engine. On some late model vehicles dating back to 1994, the wire connection inside the battery terminal connector corrodes easily. This will cause a voltage drop in the cable and result in low voltage being supplied to the starter.
You can check for voltage drop in the cable using a digital voltmeter. Connect the negative probe of the voltmeter to the negative battery post (not the battery terminal connector). Then connect the positive probe to the starter case and crank the engine. The voltage reading should be less than .5 volts. A higher reading means there is resistance in the cable or the battery terminal connector. Clean the cable end and the battery terminal connector and test again. If the voltage reading is still higher than .5 volts, replace the cable and the battery terminal connector."
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Problem solved! The negative battery cable was at fault. A visual inspection of both ends of the cable look okay. However, about a foot from where the cable bolts to the block, the same cable also grabs the frame. The insulation surrounding the frame connector was cracked. Pulling it back reveals an inch of green corroded cable rotting to bits. I installed a brand new cables all around and everything is perfect!!!

you're welcome