My for f250 heavy duty will crank but wont start. what cold be the problem?

Check the plug and number of wires going in order.

Hot does make a difference. You say it won't start, but does it crank and not start, or not even crank? If cranks but will not start, any electrical part may fail as it heats, and when you shut it off the engine gets much hotter since coolant is no longer circulating. Thus, a marginal crank or cam sensor, or coil/ignition module may work while cold of while engine is running, but fail when you first turn car off.

Sounds like moisture got to the injection system. Put some good fuel treatment in along with more gas and it should take care of it. Also, check air filter for restrictions. Sometimes rodents build a nest in the filter box.

Sounds like a fan clutch problem or ??
Can you drive it and when it quits cooling check and see if the compressor is still running ?

try adding some fuel additive for cold weather starting

Make sure the battery doesn't have a dead cell or is over two years old first. Then depending on usage I would definately think about getting a new starter. I would suspect your battery first, due to the cold weather corrolation.

Sounds like a faulty crank sensor. Can also be caused by a faulty cam sensor.

Beef up the springs and shocks!

hey Tim, I have a 90 F-250 w/ plow. Did u have overheating issues before, or did u just purchase the truck? As u know u really need a heavy duty cooling system to plow. A truck purchased for plowing should have the 'plow package' option, which includes heavy duty cooling (engine, which is usually a bigger radiator) heavy duty battery and alternator, trans. cooler, heavy duty front end (for extra plow weight). So, my question is, is this a new problem, or not? My truck is set up for the plow, but I still have to watch the temp. gauge. I only have temp issues when driving down the road, plow up, not doing the actual plowing (sounds like your problem too). The plow up position blocks all incoming air to the radiator, so try driving with the plow as low as possible, and angle it all the way to one side, this will let the air flow, and works well w/ my truck. Let me know if this works for u or not. Curt

sounds like a bad injector take it to the dealer ship and have it checked out