idi starts dies then long crank.

lraffe1 · December 8, 2011

i have a 7.3 idi in an econo line that will fire then die and then has long crank. when it does fire it starts right up and runs good. it does it after a few hours of shut off. ambient temp also does not affect it, so i do not think it is the glow plug system. i think it has a fuel drain back issue. i put a clear hose in constant return. when it is a crank no start there is no fuel returning though it. i also checked for air blubs at 3000 rpms and there is none after it is running. is there a check valve some where that stops fuel from draining back. this is before my time and probably most people at ford hotline so any help is appreciated.

Keith Browning · December 8, 2011

The fuel injector return collars were a big problem on those engines. The o-rings and the hoses and clamps particularly. Also check the rubber seals in the fuel line going from the fuel filter to the injection pump... additionally check the lift pump and the hoses there.

lraffe1 · December 8, 2011

wouldn't u see a fuel leak?

Bruce Amacker · December 8, 2011

In addition, the lift pump check valves tended to leak causing that problem, but the only way I know to check them is to remove the pump and test them on the bench (by holding your thumb on the outlet, stroking the lever once, and seeing if the inlet hisses). I might try the butcher diag of clamping the rubber hose near the lift pump and see if it fixes your problem.

I'm trying to remember if the E's had that fucking stupid water separator like the F's did- make sure it's been updated- the rubber cork in the bottom would leak fuel and suck air.

I'd also take the return valve out of the top of the injector pump and verify it's working properly (stick a toothpick is something in it and make sure it's springy, and the clear glass ball is clear.)

Why are all of these antiques coming out of the woodwork?

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lraffe1 · December 8, 2011

i came into for at the begining of 6.0s. i actual took the last 7.3 di class in cleveland. i have done my share of 7.3 di. i have manged to pass the idi on to the older techs but now that has ended because the only other diesel tech in shop was a tranny specialist then. this one is are local township water rescue that get used maybe once a year. with that being said many of the injs returns have been replaced along with hoses and some clamps. i do not see any signs of leakage around injs and there is no fuel on floor were it has been siting the last few days. how do tell if the water seperator has been replaced. it looks simialer to f's but donot know for sure if it the same.

i donot know why but i have worked on a lot of old shit lately. i put a warrant 5.8 in a 95 f250. he put a black box in it and after a year it lost compresssion. i found burnt exh vavles and several had recessed. i put in new long block. started it up and found and exhaust leak. new eng had cross over tube ports. this truck had the secoiundary air tubes in the manifold. the best part is we used the part number from his invoice when he ordered the first eng. we doubled checked again afterwards and the were the same.