Home › Forums › Bass Cat Boats › Trouble Filling Gas Tank
I have a 2016 Puma FTD. Since day 1, the port side tank filled normally, but the starboard tank has taken about a half hour to fill. I absolutely dreaded filling it and have avoided it as much as possible. So, I constantly fill the port side tank and only fill the starboard tank on those very rare occasions when I know we need both tanks during a trip.
I want to solve this problem. I’ve read the “Trouble Filling Gas Tank” post in the FAQ Archive and, as suggested, used an LED light to look down both the port and starboard fills. It was immediately apparent that the starboard side flapper was not in the right position (instead of sitting on top of the white piece, it is below the white piece, laying loose, on top of and blocking the red tube). Here is a picture of it:

I used a pronged parts grabber and was able to pull the flapper out.
Do you think this will solve the fueling issue?
Have I created a safety hazard by doing so?
Is repair a fairly simple process or should I take it to my dealer (or the factory)?
The flapper valve has been pressed down into the neck area from this image. (Nice pic) If you are the original owner, then get with your dealership and we will work through it with them. We don’t understand how the flapper got pressed down inside the tank neck? It is the diameter of the inside of the fuel line itself, and the fill neck is appx. 1/2” smaller.
We are curious is the flapper is working if you stick a solid wire probe in the neck and try to activate it?
The flapper valve does not work. The flapper itself was not attached to anything. I retrieved it using a pronged parts grabber. It is nothing more than a flat piece of plastic. Here is a picture of it.

The white plastic piece is about 5/8″ farther down in the starboard (failing) side versus the port side. I’ve attached a couple of additional pictures that may help with perspective. Here is the port side:

Here is the starboard (failing) side with the flapper removed:

I am the original owner, so I will contact my dealer.
Thanks for you help.
what was the conclusion of this problem. Mine does the same thing. 2020 Caracal.
A 2020 Caracal is a different tank liner as they are now clear. We would have your dealer check the opening and see if you have an obstruction. Also try turning the nozzle handle forwards as that works on some rigs.
Thanx
My 2019 classic has this issue frequently but I figured out what as happening… If I fill my tank until the pump kicks off, it apparently overfills it so a little bit of gas gets into the vent line through the valve on the top of the tank. Next fill up, it won’t take gas until i pull the vent hose off the top of the tank and drain the half oz or so of gas out of it, then it works perfectly fine again. Not sure if this is a possibility of your issue or not being I don’t know how those models gas tank vents are, but maybe something to look at.
MY 2019 CLASSIC YOU NEVER KNOW IF THE TANK IS FULL. GAUGE SHOW A HALF TANK AND TAKE 8 TO 10 GALLONS AND SHUT OFF,THEN RUNNING DOWN THE LAKE SHOWING FULL AND THE NEXT TIME YOU LOOK ITS ON A QUARTER TANK AND FUEL UP AND TAKE 16 GALLONS AT HALF TANK.
I’m wondering if I have a similar problem to rfhbrando with the 2015 Puma I just bought. Port tank had some discoloration on the top (see pic) when I got it. Last week I filled that tank until the pump kicked off. I went to the lake for a few hours but never drew gas from the port tank. When I got home I noticed a small amount of gas (wetness) on the top of the tank. So maybe there was a little gas in the vent hose? But since there is no evidence of this ever happening on the starboard tank, I wonder if the vent valve or the hose itself is leaking. Is there something I can check before I take it to a repair shop for diagnosis?

mark thompson:
MY 2019 CLASSIC YOU NEVER KNOW IF THE TANK IS FULL. GAUGE SHOW A HALF TANK AND TAKE 8 TO 10 GALLONS AND SHUT OFF,THEN RUNNING DOWN THE LAKE SHOWING FULL AND THE NEXT TIME YOU LOOK ITS ON A QUARTER TANK AND FUEL UP AND TAKE 16 GALLONS AT HALF TANK.
Unrelated to the filling issue… my fuel sender was bad from day one on my classic. It would read ok from 60% to 100% but once it dropped to half tankish it would go to zero and not read. I replaced it a couple months ago and manually ran the float up and down to watch the gauge react, and seems good now. Haven’t had it out much to run the fuel down. Might be something to pull out and check how the gauge reacts if you have time.
BillBo,
The factory has a kit to fix that staining issue.
BCB
My 2016 Caracal had the flapper broken off and laying down in the hole too. I removed it the same way as listed above, extended tool grabber. I notice there is fuel in the vent at the top of the cap area where you fill the tank. That looks like it should be just air for ventilation. My question is where is the vent tube for me to remove to remove this pressure and get back to fueling? BTW, I bet these flappers break when we try to fuel but the pump keeps kicking off, thus we move the stupid nozzle around trying to make it go faster, then boom… it must snap that off.
@Basscat – There is no dealer close to me in Waterloo, Iowa. Can I buy this part (gas cap part) and replace it with new? Thanks
They have the new flapper with the cross hairs at BCB. The cross hairs protect the flapper, though they also can aerate the fuel and nozzle angle is critical.
The system has been similar and direct fill since 1988 on Dual tanks. The newer fuels and EPA systems do cause more blow back and filling problems. Anyone remembering a 1992 Pantera II can a validate that the system works without the fancy system back then. Today we have to angle the handles for just the right flow line.
I have had the same issue with my 2021 pantera classic since day one. I found that inverting the handle in the filler neck and then starting to fuel slowly allows me to keep a steady stream of gas pumping. The key is to not go over about 1/3 on the pump handle. It takes a bit longer to fill, but no blow-back issues.
© 2026 Bass Cat Boats

