I am having a problem filling my Workhorse chassis gas tank. Let me start off saying it always was a little slow to fill, had to find the happy point of correct angle and correct flow speed. This last attempt took me a half hour to put in 15 gallons, kept shutting off every time I pulled the trigger and did back splash twice on me. It was a level location at Sam's Club and never had this happpen this bad. I had a mobile mechanic come to my home and pull the entire gas fill tube, 9 feet, and vent tube off, ran air and a rubber hose through the lines and was determined there was no obstruction. He also visually checked inside the tank and saw nothing that would cause the back up. He did feel that there was possibly not enough of an angle to allow the gas to flow freely into the tank, which I agree that the angle is slight. He took the last portion of the fill assembly( 1 foot piece where nozzle is inserted) and is going to try to find one with a shorter angle that would provide more of a down hill slope. It seems to make sense but just curious if anyone else has or had this problem and have you found a solution. I might add that I first suspected a faulty nozzle on the pump but I returned with my truck and used it and it worked fine. I know one way would help and that would be to raise back end with my jacks but that wold be a last resort. Any comments or suggestions would be appreciated. I have owned this MH for about 8 years and this has just developed. I might add that the tank is not full, should have been able to add a total of about 50 gallons. Thank you, Don.

I had the same problem. One of the ties broke and the vent tube slipped below the level of the fill tube. The tank won't fill if it can't exhaust the air. I moved the vent line to the upper side of the fill tube and retied it.Problem solved.Jon92 Ultrastar 339TB5.9 Cummins, MC16-FD Oshkosh

Friend who had a similar problem a while back got to poking around in the filler neck with a piece of clothes hanger wire and found that somebody had stuffed a rubber glove in there on top of the anti-theft spring, which blocked the filler neck enough to cause the problem. When he pulled the rubber glove out, the problem was solved.

With the price of fuel these days, It just wants you to think that you're gettin more for your money. ;-)

We had this type of problem on the last motorhome we had. I discovered, finally, that there was a dip in the vent line. Took the dip out of the line and problem was solved.Ed

Hi,I am surprised that this happened after you had the mobile mechanic look at it. The same thing happened to my buddy's 1987 motorhome too. I drove 1500 miles back to Kentucky, and got so frustrated - I knew it should be taking more to fill the tank, he knew it too, said if the front passengerside was not downhill, it would not fill. In Kentucky, I had tools and took apart the vent line. IT actually wrapped around the fill line, so it always would fill with a tiny amount of gas, then no air can get out. Straightened it, shortened it, and now it slopes correctly to the filler tube. On the way home, one stop we where below E and able to add 36 gallons! Before the max we where able to add was something like 24 - 26 gallons @ 8 MPG that was very frequent stops for fuel. I also installed a 16 gallon front tank, now he can run the rear one dry and switch to the forward tank and get a total of 39 gallons in the back one.Check out the vent line again, and shorten it if required to get it flowing uphill, so any gas will drop into the tank, any air up to the nozzle end. With my 75 F-350, I bought another filler tube from Transferflow.com and installed it. Then I was able to modify the vent line to get it to vent properly into the filler tube before installing it on my truck. I was able to fill it quickly after that time. Before if the pump put out more than about 5 gallons per minute, it would stop all the time while filling the rear 20 gallon tank, and it had been replaced with a 40 gallon tank. Once modified, I could get in all 40 gallons no problem. (it also had a front tank, so I could run either dry (but never both))Fred.

Filling up gas tank problems | Good Sam Community

Fifty4F100
Explorer
Jun 05, 2014
I have this same problem on and off. A few times our Holiday Rambler will fill up with no problems. Most of the time it starts acting full and when we take off, its showing 3/4's full. The last time I was able to slowly fill it to the top pumping very slowly at a Wallyworld in Mountain View, AR. I took mine all the way off (had to replace the radiator hose I used as a stopgap last year) and cleaned out the vent. There is a slight dip in the metal tube vent before the rubber line. We'll see at the next fill up.
don_b1
Explorer
Jun 03, 2014
i do not have two fill location, only one at rear of MH as illustrated in a previous post. The picture post was an excellent illustration of the gas fill mounting tube. Mine was mounted flush to MH body and I can enter the fill pipe without any problems. I do have a short fill tube and vent tube on the passenger side of the tank but they are plugged, assuming this is a universal tank and has fill tubes on both sides for another brand MH. I am thinking if the upcoming repair does not work, that I might unplug the spare 3 inch long vent tube and run an auxilary hose to the fill tube at rear of MH and install a Y and use both hoses to vent. Thanks again for all the replies.
I_rv
Explorer
Jun 03, 2014
you did not mention if you have 2 fillers,my tradewinds would not fill until i discovered i had to loosen fuel cap on oppsite side from where i'm filling and problem is gone. hope you can solve this simple.
GREGORYJ
Explorer
Jun 03, 2014
I also had this problem on my 05 Dolphin. I also found it difficult to property insert the gas station fuel nozzle because the angle of the filler pipe and the body of the RV. I found the RV's filler pipe wasn't installed correctly from the factory. The rubber hose length below the filler pipe had to be cut back as well as the vent hose. The vent hose needs to be straight, no dips, and above the main filler hose.
don_b1
Explorer
Jun 02, 2014
Thanks to everyone for their helpful replies. It seems that most of the cures resulted in an alteration or repositioning to the vent line. Since the entire fill tube and vent line was removed for trouble shooting I can not positively determine if the vent tube is the entire problem, although it seems it might be. I am going to give the mechanic time to locate another fill tube, which hopefully will give more of a flow angle. We will reassemble everything, with the positioning of the vent tube in mind, and than hope it works again. Thanks again, Don. I will give the final results as soon as I find out from my test run, might be a week or two.
Bumpyroad
Explorer
Jun 01, 2014
my vent line was hooked to a metal J trap molded into the gas fill fitting. another thing they tried was to saw out the J which could clog with gas and hook the vent hose directly onto it. that didn't help much.
and some of the units were vented with a hose within a hose?
bumpy
dkreuzen
Explorer
Jun 01, 2014
Had a similar issue with my boat. I added a second vent line and never had a problem again. Like others have said, it's most likely the vent line.
Bumpyroad
Explorer
Jun 01, 2014
my winnebago on a 1999 ford chassis had the same problem. dealer raised the fill spout about 3/4 inch, didn't help much. Ford fought with winnie about this. after a couple of years they split cost of replacing gas tank. had some kind of sock for protection in case of roll over. could lower jacks on one side which helped a little.
bumpy
Turbo_Diesel_Du
Explorer
Jun 01, 2014
Sounds like my boat on the right tank. Takes forever for 22 gallons Left side is OK. Just had tanks pumped and cleaned due to 30 years of crud accumulation. Runs likes champ now even with a 1987 140 horse. Really nasty stuff came out. Lost about 35 gallons of gas.
Golden_HVAC
Explorer
Jun 01, 2014
Hi,

I am surprised that this happened after you had the mobile mechanic look at it.

The same thing happened to my buddy's 1987 motorhome too. I drove 1500 miles back to Kentucky, and got so frustrated - I knew it should be taking more to fill the tank, he knew it too, said if the front passengerside was not downhill, it would not fill. In Kentucky, I had tools and took apart the vent line. IT actually wrapped around the fill line, so it always would fill with a tiny amount of gas, then no air can get out. Straightened it, shortened it, and now it slopes correctly to the filler tube.

On the way home, one stop we where below E and able to add 36 gallons! Before the max we where able to add was something like 24 - 26 gallons @ 8 MPG that was very frequent stops for fuel. I also installed a 16 gallon front tank, now he can run the rear one dry and switch to the forward tank and get a total of 39 gallons in the back one.

Check out the vent line again, and shorten it if required to get it flowing uphill, so any gas will drop into the tank, any air up to the nozzle end.

With my 75 F-350, I bought another filler tube from Transferflow.com and installed it. Then I was able to modify the vent line to get it to vent properly into the filler tube before installing it on my truck. I was able to fill it quickly after that time. Before if the pump put out more than about 5 gallons per minute, it would stop all the time while filling the rear 20 gallon tank, and it had been replaced with a 40 gallon tank. Once modified, I could get in all 40 gallons no problem. (it also had a front tank, so I could run either dry (but never both))

Fred.