Not sure what this part is but its behind and below the fuel filter. I can't tell exactly where its leaking from it right now. Its either on the bottom of it or on the block side where I can't see it.

Its only leaking when the truck is running but at a pretty good pace of about a drop a second. I got to work this morning and smelled it, invesitgated and the whole underbody of the truck was dripping diesel fuel. I can't afford to be loosing fuel and I'm scared to drive the truck right now.

Anyone know what this is and why it might be leaking? Thanks.

 

I hope this doesn't sound too stupid but you didn't say anything about it so I have to ask, Did you check your water drain valve it might not be closed all the way.

 

x2 good place to check first

 

Nope doesn't sound stupid at all, this sounds stupid-I didn't know I had that and still don't know where it is. Thanks for the reply.

 

If it's behind and below the fuel filter canister, it's either the Lift pump: or if your LP has been re-located into the fuel tank by the dealer, it's the block the dealer installed for the original hoses can splice together.

 

Fuel leaks can be a pain to find out where they come from sometimes. First things first I would spray some brake clean all over the area where it looks like it is leaking from. This will help locate where the leak is originating from.

 

And don't be too afraid. It's just diesel. It doesn't ignite like gasoline. Besides there is nothing hot that could cause a fire on that side of the block. With that being said, I'd still repair the leak ASAP.

 

Thanks guys. I crawled in and under this truck a handfull of times and while I can see it dripping I can't tell exactly where its coming from. I can't get it looked at until monday and I don't plan on driving it more than once until then. I use a local diesel shop btw.

 

Get some rags, towels, etc. and wipe off the fuel on the filter canister, and the lift pump.

Now, start and idle the engine. Since you have wiped off the fuel, use your hand and feel both the lift pump and fuel filter canister, and feel which one gets wet first.

Do you still have the drain hose connected to the fuel filter canister?


Here are some pictures to help you.

This first one is the lift pump and the fuel line that connects it to the filter. The filter canister was removed for this shot. The lift pump is the cylindrical object just behind and to the right of my catch bottle.


Also check the filter housing. The fuel drain has been known not to seal well sometimes. Also, sometimes fuel leaks out of the electrical connections. Fuel leaks from the housing often end up misting fuel all over due to the close proximity of the radiator fan.

 

Some good tips here.

I had a washer split under one of the banjo bolts and caused a slight leak that was hard to chase down.

Dave

 

Have seen some leak at the water drain. It is kinda hard to tell where it is coming from. Changed my 98.5 to the newer model cannister and it started leaking within about 1.000 miles. The kit cost $8 at Cummins. Think they cost about 6 times this at the dealer.

 

I'm not sure if I did the pics right or not. One pic shows the valve up close, the other pic shows where it is located on the filter housing (right below the close/open arrow.) From what I've heard some valves are yellow, mine is black. I will try and get my scanner up and running so I can pm (or if you want to pm me your e-mail) I can send the whole page to you. Take care!! I pray it's just the valve!!

 

Thanks so much for the pics, thats really what I needed....and maybe a lift pump?

I dried everything off and had the truck started while I was underneath it. It started dripping instantly from the bottom of the lift pump, off of the rubber/electrical fitting. Still really can't tell where its coming from though. Guesses?

 

I think you nailed it. The lift pump. Either a loose banjo bolt (fuel line fittings) or the electrical connection itself sprung a leak. If the fittings are loose, its an easy fix. If it's the electrical plug leaking, your best bet would be to replace the lift pump.

 

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