I've had the Titan fuel tank installed for about a month now and am loving the extra range, although this morning I walked by the truck and got a slight whiff of diesel by the fuel filler door. I pulled out the flashlight to take a look, and noticed a really small, faint trail of diesel fuel running down the driver's side of the tank near the rear strap.

I crawled under the truck to inspect it as best as I could in the driveway, feeling around the sender, filler, and vent tube connections, and didn't notice any obvious puddles of diesel. About the most I got was some dampness around the sender unit seal, but it wasn't much, and could even be residue from the fuel lines dripping during installation of the tank. Based on where the trail down the side of the tank has formed, my best guess is it's going to be a filler or vent tube hose clamp that I didn't get tight enough.

Unfortunately I just filled the tank up last night and am headed out camping for the weekend this morning. I followed all the install instructions exactly, making sure to check the torque on the sender unit seal four times before installing the tank back in the truck because I didn't want to deal with any leaks, so I really hope it's not that seal. I also filled the tank up to the brim right after install and crawled all around it a day or so later and noticed no dampness or leaks. Needless to say, I'm not looking forward to dropping the tank again and then potentially waiting on parts if something is defective. I'm waiting on a call back from Titan to get their advice.

Below are a couple pics of the weepage. Obviously not a huge leak, but something I want to get taken care of ASAP.

 

My concern would be if diesel can get out, water could get in. There isn't much room to see above the tank but I would fill it up to the very top of the fill tube and get a mirror up there to see where it is coming from. The sending unit is recessed on the top, so if it is coming from there it would allow water to get in if you were driving in the rain. If it is leaking from a hose clamp water won't be able to get in based on physics, it would still need fixed, but not as critical.

Just my opinion.

 

take care of it soon! there has been some anecdotal evidence by other members on this site that there can be water entry into your tank and then ingested by the HPFP causing a huge non-warranty repair bill.

 

Your tank installer did not follow Titan's explicit instructions for installing the sending unit assembly.

At least that would be the first thing I looked for.

 

Oops - I missed that you did it yourself - I would still be looking there first.
I'm assuming you did check the fill hose connection?

 

Thanks for the responses so far guys, although they're not helping alleviate my biggest worry about driving the truck; water ingestion into the HPFP.

I crawled back under there with my camera to take another look and was able to get some pictures of the sending unit area and filler and vent tubes. They weren't the best, but I could see more than trying to get my head up in there. The area around the sending unit feels dry and I confirmed the trail I'm seeing down the side of the tank is dripping 100% vertically from the area where the filler tube, vent tube, and what I'm assuming is the rollover valve (brass fitting with a small, capped vacuum line on the end of it) is located.

It looks like there is a cutout molded into the recessed area of the tank where the sending unit is installed that would allow any buildup to drain off to the driver's side of the tank and this area is totally dry. The trail I'm seeing starts higher up and further back on the tank, so I am 95% sure the sending unit seal isn't compromised. The clamps around the filler and vent tubes feel tight and there's no noticeable leakage around them. I did notice a small buildup of diesel smelling dirt where the rollover valve tubing terminates and is capped, which lines up almost perfectly to the drip down the side of the tank. Is it possible the rollover valve is allowing very small amounts of fuel to leak out when the tank is filled to capacity and fuel is sloshing around?

At this point, I think I'm comfortable driving the truck for this weekend's trip because I need to burn some fuel out of it before dropping the tank anyway, and now that I've wiped everything down, I can see if the drip comes back. What do you all think? If I really should park it, I do still have the trusty old 7.3 that I can hook up to the trailer and go.

 

I think if it was me, and no rain forecast, I'd go enjoy my weekend, worry about it later.
And if you have to get fuel during the trip, only half fill it each time.

 

I had the exact same thing happen the First time I filled up my new tank. I though O ****! So, I wiped the tank down, kept checking it daily til the tank got low. No more drip, leak, whatever. So I decided to fill it again and see what happens. Now a year later, and I have never had a drip, leak, or any signs on the tank of a leak.

I think is was just from fuel in the lines when I reattached them to the tank, and it gathered on top of the tank.

I say run it. But keep checking it. If the tank is "wet" again then i would drop it and check all the fittings.

Paul

 

I took a video camera and a light to get as good a view as I could of the top of the tank and nothing looked wet or out of place, so I thoroughly wiped everything down, especially around the sending unit so I can see if any new leaks start. I was relieved that although there was some water I wiped up around the sending unit seal, the towel didn't even have the slightest smell of diesel on it when I was finished. I even drained some fuel from the water separator and nothing but clean looking fuel came out.

I now feel comfortable taking it on my trip this weekend, but I'll be keeping a close eye on everything. The good news is I won't have to fill up this trip thanks to the extra capacity of the Titan tank, so the fuel level will be low enough when I get home that I can safely drop the tank if I need to.

Paul, I sure hope I have as good of luck as you and I don't have to take everything back apart; that would be a huge relief! Thanks again for the input everyone and enjoy your weekend!

 

My tank i installed was doing the same thing every time i filled it up. I contacted titan tanks and talked with James who was very helpful. He had me torque the sending unit bolts to 24 ft lbs from the 20 ft lbs which the directions called for. He assured me everything would be alright and that the studs were designed to hold 40 ft lbs. So i did it and now absolutely no leakage every time i fill it up. Also push down firmly on the two fuel lines to insure they are completely seated. Hope that helps.

 

I have had the Titan tank in my 2015 for over a year and half with no problems. When I had it installed, I re-torqued the sending unit nuts twice. I then pressurized the tank to check for any air leaks that might leak fuel after install.

 

I had some time and a low enough level of fuel in the tank to drop it over the weekend to see if I could figure out where it was leaking from. I found it; it was the 90 degree fitting for the vent tube. The original one was broke off from shipping when I got the tank, so I installed the spare included in the box and probably didn't use enough Teflon tape.

I reinstalled the fitting with much more tape and then used RTV around the seal once it was installed for a little extra insurance. I also made sure the hose clamps for the fill and vent tube were extra tight and rechecked the torque on the sender unit nuts. Fortunately it wasn't leaking from the sender, but I was able to get a couple of the nuts to turn another 1/4 or so before the wrench clicked, so I'm glad I checked them while the tank was out.

I also noticed I could move the nose of the tank around in the front bracket before dropping it, which is likely what I was feeling when it was near full and coming to a stop. To fix that, I installed one of their rubber bushings on the front bracket and now the tank is much more secure and I can't get it to move at all.

All in all I'm happy I went through the effort to drop the tank again. I was really happy the leak wasn't around the sending unit, and I drained some fuel out of the water separator once again and got nothing but clean diesel. One thing I noticed is the gallons used isn't very accurate. The truck showed I had burned 43 gallons, but there was A LOT more than 7 gallons remaining in the tank when I lowered it!

Below is a pic that shows where it was leaking from: