Fuel leak

Topic: Fuel leak (Read 1984 times) previous topic - next topic

Fuel leak

January 22, 2019, 09:54:42 am

Pulled into the Pilot in Quartzite to refuel yesterday, and while refueling noticed a slow drip, - drip, - drip under the engine. After refueling and taking on 90+ gallons we had a wet spot under the coach the size of a small paper plate. Realizing that there are thousands of coaches are at the Q and probably all repair shops are busy I decided to make the 3 hour trek to my sister's and monitor the problem. Upon arriving at my sister's a few hours later was still seeing the drip, drip drip while the engine was running. Shut the engine down after we set-up and opened the engine compartment door and saw moisture on the right side of the engine and smelled diesel. No drip, drip, drip when the engine is not running.

Will contact Northern Arizona truck repair to see if they can get us in. Guessing have a small leak either going to the engine or returning to the tank.

Re: Fuel leak

Reply #1 – January 22, 2019, 10:04:57 am

Did you have filters changed recently?May be something you can tighten?

Re: Fuel leak

Reply #2 – January 22, 2019, 10:06:45 am

You have a fuel filter, the fuel line from the primary filter to the secondary filter and the line from the engine to the fuel cooler in that area.

Re: Fuel leak

Reply #3 – January 22, 2019, 10:10:39 am

Scott,

I know you have a different Cummins engine, but I suspect the fuel line plumbing follows a similar path. I recently had a fuel leak with the exact same symptoms. Thread below might give you (or mechanic) a clue to one possible source of leakage:

SAFETY ALERT: C8.3 Fuel Leak

Re: Fuel leak

Reply #4 – January 22, 2019, 10:35:30 am

Scott we will be back in camp Verde next week if you want to wait we can come over and take a look at it. There is a guy in cottonwood that might be able to look at it. Just a thought.

Re: Fuel leak

Reply #5 – January 22, 2019, 10:40:52 am

Thanks for your prompt responses.

Yes the filters were recently replaced in Houston, but the leak appears to be higher and looks like it is near a metal elbow below the valve cover.

Andy - would like to take advantage of your offer. Lets connect after you get settled in the Verde Valley.

Re: Fuel leak

Reply #6 – January 22, 2019, 10:41:53 am

Scott,

Can you post a picture of the leak source?

Re: Fuel leak

Reply #7 – January 22, 2019, 10:54:48 am

Hey Brett - Will try, but hard to get an eyeball on it - hoses and stuff.

Awfully cold outside this AM - 30F. Will try to get a better look-see later today when it gets warmer from the top-side.

Re: Fuel leak

Reply #8 – January 23, 2019, 01:57:31 am

I recently replaced three metal fuel lines in the area described. They can be seen from the top if you can access the engine compartment from under your bed. Hopefully the fittings can be tightened. This link should show the lines I'm referring to: https://quickserve.cummins.com/qs3/portal/parts/option_detail.html?path=/qs3/parts/99/ii/06.03/ft22072-06
Cummins Quick Serve is a great resource. You would need to register your engine # in order to find the correct parts.

Good luck

Re: Fuel leak

Reply #9 – January 23, 2019, 02:19:28 am

Here is an amateur video from a mechanic that shows the fuel lines to the fuel pump, ECM then into the engine where it will deliver fuel to the injector pump. These are the lines I replaced and is much better than the photos I took. It is looking down on the engine from the top starboard side of the engine (back half if you are kneeling and bending over the pedestal. The useful part starts at about 4:30 on the video. https://www.youtube.com/watch?v=_8E9ddfKGrE

Re: Fuel leak

Reply #10 – January 23, 2019, 08:14:50 am

Scott,

I had a couple of fuel leaks that I tracked down. With the leak that you have, you should be able to clean the engine and then start it and watch for the leak. It takes a lot of twisting and turning with a good light.

One was on top of the engine where the metal fuel lines to each cylinder attach to the top of the engine and the other was at the other end of the same lines. I also found that the spacer blocks (blue plastic on my engine) that keep the metal fuel lines from rubbing were missing in a couple of places. I caught this just before the metal lines wore through. They are very tangled as they go to the engine from the fuel pump. Inspect them closely. They should not be touching each other. They are very stiff and won't move much but you can look for places where they could be touching/rubbing.

Hope this helps,

Rich

Re: Fuel leak

Reply #11 – January 23, 2019, 09:23:28 am

If the leak is coming from the connection at the ends of the metal fuel injector line do not just tighten the connector. Usually it will not stop the leak if you just tighten it. If you loosen the connector first, then tighten it you will have better results.

Re: Fuel leak

Reply #12 – January 23, 2019, 09:48:22 am

Thanks guys -

Supposed to get up to 54F today. Will take a look this afternoon.

Re: Fuel leak

Reply #13 – January 25, 2019, 03:16:40 pm

Pic attached.

Is that the fuel feed to the engine or return?

I torqued the fitting a bit and the leak partially moved from the engine fitting out through the flange fitting. Can't see where the metal tube goes.

Re: Fuel leak

Reply #14 – January 25, 2019, 03:52:03 pm

Split line

Re: Fuel leak

Reply #15 – January 25, 2019, 04:02:25 pm

Scott, looking at mine it looks like from above it would be an easy change out. Like you it is hard to see from the rear, but is a short metal line.

Re: Fuel leak

Reply #16 – January 25, 2019, 04:13:08 pm

Sven just did that line plus the others, maybe he'll chime in with which line that is.

Re: Fuel leak

Reply #17 – January 25, 2019, 04:47:45 pm

It looks like a short piece of tubing and is probably the fuel feed line. Can see where it's attached. Would guess it's connected to the fuel pump.

The other line - guessing it's the fuel return, looks extremely corroded too.

Re: Fuel leak

Reply #18 – January 25, 2019, 05:03:30 pm

Fuel line to injector from the ecm cooling plate. Now to find the part number and locate the part.

Re: Fuel leak

Reply #19 – January 25, 2019, 06:03:32 pm

After talking with Cummins the Part # is: 3161618.

Available from: 3161618 | Cummins Fuel Supply Tube | Diesel Parts Direct

Re: Fuel leak

Reply #20 – January 25, 2019, 09:04:14 pm

Ordered part from Cummins. 2 day delivery. Will be installing Wed/Thurs next week.

$45+/-.

Re: Fuel leak

Reply #21 – January 25, 2019, 09:20:27 pm

My advice on any nut and or bolt use anti-seize,can get at Auto-Zone.

Re: Fuel leak

Reply #22 – January 25, 2019, 11:48:44 pm

Any other thoughts or suggestions?

Re: Fuel leak

Reply #23 – January 26, 2019, 12:09:45 am

Waiting on parts sucks, especially hoses that may be sourced locally. Learn to identify fittings, they may be AN fittings which may be sourced at local hot rod shop, along with cut to fit hose. Ask about Earl's or aeroquip. Or a local hydraulic hose shop, lay it on the counter, tell them what fluid it carrying, walk out the door 20 minutes later with a replacement. Maybe cheaper.

Re: Fuel leak

Reply #24 – January 26, 2019, 12:40:31 am

Thanks for the suggestion Phred. Thought of trying to source local but decided to get the part from Cummins. It has 3 or 4 - 90 deg. bends so I thought I would play it safe. I also have never replaced a fuel line before. Looks like I should be able to make the exchange. I also have a plan B if I get cold feet- Local RV service company is a Cummins Preferred provider - what ever that means.

We are parked in my sister's driveway for another week.

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