Fuel under air filter and intake.

I have fuel pooling under the air filter on top of the engine. My guess is it’s the injection pump. If there is another reason that fuel could be there please let me know. The truck runs fine and starts fine. If it is the IP who has experience with a good shop they recommend getting it rebuilt at? Thanks ahead of time!!

I'd replace the rubber hose from the filter before I had the IP rebuilt on a good running truck.

After the hose mentioned above is replaced. The next most likely leak is the o-rings on the throttle shaft. They probably won’t leak with the engine off or cold. Shining a light on either side of the IP with the engine warmed up and running might show you the leak. That is how 3 of mine have behaved at least.

If all of the above is dry. Put a light on the injector lines with the engine running. It could just be a simple loose fitting.

Barrman said:

After the hose mentioned above is replaced. The next most likely leak is the o-rings on the throttle shaft. They probably won’t leak with the engine off or cold. Shining a light on either side of the IP with the engine warmed up and running might show you the leak. That is how 3 of mine have behaved at least.

If all of the above is dry. Put a light on the injector lines with the engine running. It could just be a simple loose fitting.

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Agreed. Could be a tiny leak. You just don't notice it until it has made a mess, kind of like how my water heater flooded my house one drip at a time. If necessary, you could put florescent dye in your fuel filter to help you find it. When the IP goes, the truck will start and die immediately. Run a little and die at random. Leave you stranded. I doubt it needs to be rebuilt to remedy this issue.

CARC686 said:

I'd replace the rubber hose from the filter before I had the IP rebuilt on a good running truck.

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Do you happen to know what size fuel line I will need for that? I completely forgot about that line under there coming off the filter. I saw fuel under the truck looked at the top of then engine while it was running and got pissed lol I was not thinking clearly. Thanks for the advice.

I replaced mine last year. I want to say 5/16", but that's my best guess and I don't stand by it. If you lay on top of the engine, you can reach under the intake and yank it out from the firewall side without having to remove the intake. Then, you'll have a hose to take to the parts house.

1/4” ID is the hose size from the filter to the IP.

I like putting a lawn chair pad over the radiator and front of the engine to lay on.

So I got some time today to look at the truck again. I cant get it to leak now. Ive dried out the area under the intake and it’s no longer leaking. I see no fuel on the hose coming from the filter or the steel lines, they are all dry.
It runs fine but Im perplexed as to where the fuel was coming from. It looks like the moister originated from the mounting point of the IP.

It was very cold here in Texas when it was leaking.
Could the cold weather have caused something to shrink and allow a leak to form and not its warm its expanded again? Any advice would be great Im all ears.
My son has one as well, he said "yea sometimes they just fix themselves." I dont know if my need to fix and repair leaks can handle that line of thought.

check around the lift pump