Ford Repair: Starting Problem - 1991, 460 Super Duty Ford Van Gas., battery cables, ford van

Question
I have a Ford Bucket (Aerial Lift) Van and have had a problem with it sometimes starting, sometimes NOT! It will start imediately if I let it sit for a while. after that, if I start it, turn it off and restart it over and over I can do this just fine all day long. But after running it idle in park for 15-20 Min or more the van will not restart. Also, almost always, when I go to start it the starter seems a little slugish at first then kicks in. I have replaced the battery (it needed replacement anyway), the alternator (Rebuilt-OEM), the starter relay (OEM) and the starter itself (Rebuilt-OEM). None of this has fixed the problem. When I turn the ignition durring these non-starting incidents, the starter will sometimes try to engage sluggishly and sometimes just a click like the battery is dead. I have read your responses to other starting issues and wonder if this problem might be an overheating issue, ie. water pump or a heat sensor? Would this cause the starter to act like no juice was getting to it? I know the engine gets super hot after running it for only a short while, especialy now here in Florida... Please Help!

Answer
Mr. Byrne,

have you changed your cables?. i would change the battery cables the cable to the starter and to solinoid. a bad solinoid will cause this also. have somone try to start the truck and then feel the cables mentioned and see if they are warm. if the cables are warm replace them as the resistance in the cable is high.if the cables are ok then you have a fuel problem, more than likely when your enbine gets hot its vapor locking,like the carb trucks used to. i dont know if ford used a heat sensor in this year truck.but if cables are ok its a fuel problem,autozone or advance will scan your truck for free.hope this helps.

ken