won't start when engine is hot

66 econoline with a 240 and manual transmission. Replaced the starter, solenoid, battery, both cables from the battery to the solenoid and to the block. Replaced positive cable from solenoid to starter and the ground from where the starter bolts up to the dog house. When engine is cold cranks great and fires right up, when engine is hot barely cranks and won't start. Anyone have any ideas cause I'm pretty much lost at this point.

I wouldsay check your timing. sounds like it might be too far advanced

Adjusted the timing still no change. When I turn the key the starter engages like it should but will not even turn the engine over a full revolution.

Jay, Our trucks are famous for this problem. you need to find a way to remove the heat from the doghouse after shutdown. I installed a fan from a ford Taurus in my 289 powered pick up. I hooked up the low speed side to a fan controller and set it to run for ten mins after shutdown,never had a problem after that you will need to upgrade the charging system too. lots of Taurus conversion, and 3 g alt upgrades online. mick

I would pull the coil wire off and see if the engine cranks normally to eliminate any type of spark advance problems when you have a hot start problem,,,,,,,,,,,and hook a jumper battery on the truck battery to see if that helps,,,,,,put a voltmeter on the battery,,,,,,see if the voltage drops below 10 volts when cranking, cold and hot,,,,,go get us some clues to see what you got,,,,,,

Thanks I'll try that when I get home. I did try to start it this morning and same thing, I did pull all the plugs and it cranked like it should.

My was doing that and the mechanic said it was vapor locking. . The engine capartment get to hot and turns the gas in gas line into vapors . It won't start until the gas lines cool down . This may sound crazy but I did it and it help . Put wooden close pins on the fuel line . Some how it draws the heat from the lines and keeps it from vapor locking. I later insulated my fuel lines and put a fan on radiator . Haven't had no more problems .

I appreciate all the info, over the years I've owned 8 early vans and this is the first time I've run into this problem.

ill ask =?? is the problem only when Hot & wont Crank?? or=slow to Crank? or?=  wont fire & start? --- also = Brand NEW Battery?or used one? Brand New Starter?or =?Rebuilt?

You just want to disable the spark by removing the coil wire or one of the primary wires on the coil,,,,this eliminates the distributor as the problem,,,,,,but it could just be a bad starter,,,,,

Starter is a remanufactured from advanced auto, everything thing else is brand new. I'll pull the coil wire and see what happens when I get home.

Twinpilot001 wrote:ill ask =?? is the problem only when Hot & wont Crank?? or=slow to Crank? or?=  wont fire & start? --- also = Brand NEW Battery?or used one?  Brand New Starter?or =?Rebuilt?

I bought a van that has been sitting for 11 yrs. Last year I pulled the tank cleaned it replaced fuel line and got it running. Haven't tried to start the van until this past Sunday and when I tried it wouldn't crank. When I turned the key the starter would engage but wouldn't even turn the engine over a full revolution. I put in a new battery, cables,solenoid, & a remanufactured starter. Once I did all of that the van fired up I drove it a few miles brought it home and shut it off. About 10 minutes later I went to start it to pull in my garage and it did the same thing it did before I replaced everything. This morning before I went to work I tried again and same thing.

,,,,if now it won't crank when cold, check to see if the coolant level in the radiator has gone down meaning that the head gasket is blown and there is coolant in the cylinders now,,,,,

I will and I'll let you know what happens when I get home tonight, thanks.

donivan65 wrote:You just want to disable the spark by removing the coil wire or one of the primary wires on the coil,,,,this eliminates the distributor as the problem,,,,,,but it could just be a bad starter,,,,,

Came home from work got in the van and it fired right up. Backedn it out of the garage let it come up to operating temp idling for about 15 minutes. Pulled it back in the garage shut it off and now it won't crank over, pulled the coil wire like you suggested and still the same.

Im going back to either starter or battery!! Yet -ill ask --is this a new engine??

No its not new and unsure of the mileage.

Is the charging system working,,,,,,whats the voltage at the battery when its running and also when it wont crank,,,try another battery or jump it and see if that makes it crank,,,,,

likely =Battery

Well this morning before I went to work jumped in and it fired right up. Hoping its just a defective starter

Finally figured out why it wouldn't start when hot. Found out that fly wheel is 2piece and when the engine got hotter starter would spin the ring with the teeth on it but not the pressure plate.