Hello. I currently have a fuel leak on my 1992 Ford F-250 7.3 idi. The fuel seems to be running from or down the starter. All fuel lines seem to be try. Where could it be coming from?

 

fuel leaks into the valley pan drain out the back of the block.

 

Check the return line the goes between the back two injectors (7&8), it dips down out of sight and it’s usually dark and dirty back there. It’s 5/16 hose if it needs replacing. There’s a lot of places for these engines to leak fuel from lol

 

Starter is on Passenger side RARE to see fuel to leak on the starter... more often it is coolant or oil

 

OP I think I’m wrong, it would be 1/4 inch hose back there. Going down from the brass T to your hard line back to the tank is 5/16.

lonewolf I’ve had fuel leak onto my starter, and also fuel pour onto the exhaust pipe crossover when that short piece of 5/16 hose cracked. I was just pulling out of the yard thankfully. The original hose lasted pretty good.

 

I just did all my fuel return hoses and injector caps yesterday. If you find fuel is leaking from one of those, be advised that there are two different sizes depending on the year. Make sure you get the correct parts kit. Split was around '89. This article proved to be very helpful 6.9L & 7.3L IDI Diesel Fuel Injector Replacement Procedures (dieselhub.com)

The fuel heater can also leak and I could see that maybe blowing back onto the starter if it's leaking heavily enough. It's on the passenger side on top of your fuel filter.

 

There does not seem to be fuel on the valley pan.

 

It is definitely diesel

 

yes. That seems to be the same problem I am having. It drips down the starter then there is a pretty steady drip down onto the crossover pipe. But I checked that hose and could not see any problems with the line. I will do a closer inspection on it.

 

That hose goes to a t back there. Some of them had an olive in there and would just loosen up..

 

I know this is an older thread, but I figured I’d give it a try. Currently having the same issue on a 94 7.3 NA. Replaced all the return lines including the crossover that dips into the valley pan. Doesn’t seem to have fixed it. Also installed an electronic fuel pump and blocked off mechanical pump with a plate. Fuel only drips when the engine is running, not when the fuel pump only is on. Not noticing any fuel in the valley pan.

On a side note, I replaced the fuel tanks and fuel selector valve, and also some sections of line that looked pretty rough. I can’t keep the fuel bowl primed. Obviously getting air somewhere, but no fuel leaks other than the one mentioned above. Truck runs fine when drawing fuel from a Jerry can on the ground. The leak above existed before any of the fuel tank/lines were done.

Any ideas offered are appreciated!

 

The IP itself may be leaking. I have a similar situation but I do notice wetness in the valley pan.
As to your side note I am not sure what you mean by keeping the fuel bowl primed. Do you mean fuel filter? AFAIK there isn't a fuel bowl on the IDI.

 

Yes, fuel bowl = fuel filter in my poor vocabulary. Apologies for the confusion. IP is new, and I cleaned and inspected everything on install. I don’t see anything indicating that as the source. I hooked the Jerry can back up yesterday and everything ran fine, fuel leak aside. I’m wondering if it’s possible that it’s leaking from the injector itself? Can it leak somewhere that it would run down the passenger side of the back of the motor but not be visible from the top?

 

Injectors can leak. Either from the returns, or between the injector and injector line. Did you replace the injectors when you put on a new injection pump?

 

Ultimately if there is fuel dripping down then there has to be visible moisture somewhere on top of the engine. Maybe put a paper towel under the IP while the engine is running, or stuff paper towels around the injectors?