Trouble starting when hot

I,ve got a 1989 f-150 5.8L that runs fine but does not start well when the engine is hot. When the engine is cold it cranks right over, when it;s hot the starter binds, sometimes cranking over, sometimes it just grinds till the battery drains. If I wait awhile untill the engine cools down and try it again it usually starts right up. The battery is good, the timing is on, and the starter is brand new. I also cleaned all the electrical connections I could find. Can anyone tell me where to look next?

Correction - it's an f-250!

[Phil]

Wow....I would think that you would have to make a heat shield somehow.....does the exhaust run close to the starter? That's what it sounds like to me....make a shield for the starter or wrap the pipes in that area....I've heard of this happening before.....

I have a 83 f-250 with a 460 that does the same thing. How I solved my problem was to try not to turn the key as far as you normally would. More than likley your problem is in your ignition, than your starter. you probaly have a spot worn into your ignition and when it gets hot you notice it more than when its cold

[Phillip Guidry]

When it comes to a Ford starter, you need more CCA's(cold crank amps)in your battery.Plus,the physical size makes a difference also.If you most run a Group 24,get at least a 72 month or more battery,that'll get you about 650 CCA's. In a Group 65,you can get by with a 60 month because of it's increased capacity due to larger plates & more acid.Now, none of this helps if your existing battery has a slight defect in it! Have it load tested several times at once to verify the voltage doesn't drop off after a couple of loadings.And last,if you have those emergency repair term's on your cables,replace them,don't just clean them.And change any 6 gauge cables to at least 4 ga.
Phillip