Community Forums

slate · 05-28-2023, 09:32 AM

We own a 2021 Fleetwood Discovery 44H with the Freightliner chassis. It has a fuel filler on both sides, as i believe most Class A pushers do. After i fill fuel, the filler caps leak out just enough diesel to make a hell of a mess down each side. Right hand side was really bad, likely because of the "crown" of the road, so i replaced the factory vented cap with a none vented one. The driver side one still makes a mess, and i believe, from what I read, you have to leave at least one vented. Even the none vented cap seeps a bit. I noticed the filler neck on both sides angles up, so when full, a little fuel i think stays out against the cap. I've tried not filling all the way, but i think every time i turn, left or right, fuel sloshes up into the filler necks. Both my Freightliner dealer and the Fleetwood dealer say no one else has complained about this. (Not sure I believe the Fleetwood dealer) I'm in Canada and there are not many of these models around, so maybe they haven't? The mess is bad enough, but there is also a constant smell of diesel fuel. Has anyone else experienced this? Is it fixable? Thanks in advance.

Fiesta48 · 05-28-2023, 09:39 AM

Just place a rag below the filler until you find a permanent solution. My 15 Discovery does not leak.

alank · 05-28-2023, 12:25 PM

I've got a long story about my fuel caps, won't go into it here, but going through it is how I learned to run my fuel caps and solved my problem.

On your 21 I think the filler tubes are much more horizontal than on my 2019 because of the redesign of the slide drive mechanism, which ,I'm sure is partially responsible for your problem.

The other thing is, on mine, that the filler caps have a mechanical vent built into the caps. If you leave it open, then leakage is easy, so always keep it closed while traveling.

If you have noticed when operating the cap, the top will turn nearly a full turn with no resistance. When putting the cap on, turning it clockwise, closes the vent, turning the top counter clockwise that free turn opens the vent. Then you hit a stop where the cap starts to come unscrewed. If you take the cap off, look at the very center while you rotate the top that free turn, you can see the valve open and close.

slate · 05-29-2023, 03:51 PM

[QUOTE=alank;6512180]I've got a long story about my fuel caps, won't go into it here, but going through it is how I learned to run my fuel caps and solved my problem.

On your 21 I think the filler tubes are much more horizontal than on my 2019 because of the redesign of the slide drive mechanism, which ,I'm sure is partially responsible for your problem.

The other thing is, on mine, that the filler caps have a mechanical vent built into the caps. If you leave it open, then leakage is easy, so always keep it closed while traveling.

If you have noticed when operating the cap, the top will turn nearly a full turn with no resistance. When putting the cap on, turning it clockwise, closes the vent, turning the top counter clockwise that free turn opens the vent. Then you hit a stop where the cap starts to come unscrewed. If you take the cap off, look at the very center while you rotate the top that free turn, you can see the valve open and close.[/QUOTE
Yes. Thank you. I’ve read about the vents. Even the new non vented cap seeps. On the original vented cap I know how to close the vent. But if you can manually close it, what’s the point in having a vented cap in the first place? I’m at a loss as to how Fleetwood, or Freightliner, can sell these things, apparently with no remedy, leaking fuel as you drive. I’ve read on here since I posted that this has been a common problem.

chuckftboy · 05-29-2023, 04:44 PM

I have had that same problem when I have been in a hurry and not put the filler cap on square to the neck. Because the threads are large it is easy to put the cap on at a slight angle. The cap will click and appear to be on properly and tight but will slosh out diesel as the coach makes turns

DuaneMiller · 05-30-2023, 07:11 AM

^^^ What Chuck said...

After I purchased our coach, I was experiencing the exact same issue with fuel sloshing out of the filler neck... This was especially prevalent whenever I turned sharp out of my driveway and onto the road in front of our house. If I turned to the left, then the fuel would slosh out of the right side filler neck. Or, if I filled the tank and parked even on the slightest decline toward the front, I could see fuel dripping out.

Like Chuck mentioned, the threads on the caps are very course and its really easy to cross thread without even knowing it... Since the caps click pretty easily, you think the cap is fully seated flush with the filler neck flange. Also, if you are wearing any sort of gloves to keep fuel off your hands, it makes it hard to "feel" if the cap is fully seated. Also add to the fact that the filler pipe is just about horizontal to the tank, it really doesn't make it easy.

When you screw the cap on, just make sure it is "square" to the filler flange. Ever since I have did this, I have never experienced the fuel issue again...

alank · 05-30-2023, 07:51 AM

On my 2017 Freightliner chassis coach, the filler cap came of just as you would expect it to. On my current 2019 Freightliner chassis, the filler cap was (still is) extremely difficult to get off. What I determined is that the slight suction that is placed on the fuel tank to prevent venting of fuel vapors doesn't get released when the engine is shut off. That suction held the cap on tight, and in one occasion the cap came apart while trying to remove it. Part of the cap was still in the filler neck, part on the ground and the top in my hand. The whole thing just snaps together. Went to Freightliner and they didn't understand it, just got me a new cap and it worked just like the one that came apart. I ended up switching caps side to side and they worked just the same. I finally took both into the work bench and took one apart to see the internal workings. That's when I found the internal valve and how it operates.
Now, when I fuel, I first rotate the filler cap counter clockwise that one full turn to open the valve and release the suction on the tank while I get the pump ready to pump fuel. By the time I have the fuel nozzle ready to insert, the suction is released, and the cap will come off normally. I suspect there may be a defective vent valve in the top of the tank that is shown in the tank drawings, but I haven't been able to find it.

As for those that don't put the caps on straight, there's only one solution for that.

campcarlton1 · 05-30-2023, 09:21 PM

I’ve had a 2011 Fleetwood Discovery 40g which we traded on a 2022 44B. Both would like fuel when filling them up. The 44B had a filler neck that was nearly horizontal, so much so the nozzle would barely stay on the neck. I sold the 44B due to quality issues and bought 2022 Allegro Bus 45 OPP and have never had an issue. The filler neck is much higher than the FW but overall a much better design as it’s never coughed up a drop of fuel when filling.