Topic: Trouble filling Gas tank

Keymaster

This is going to get a lot of eyes, so we are going to be extremely in depth in our explanation. This is a part of the comedy joke some will have seen about how the government screwed up a gas can. Some is about how the government is messing with our environment.

The short note is to try moving the nozzle around to get a better angle, usually the handle pointing to the center of the deck is best. Further explained long down into this writing.

We never had this problem on this original design in 1988. Much of this has to do with several factors people simply don’t realize today. The fuel line itself is a straight shot down from the cap to the fuel tank we started using in 1988 model year. It would seem nothing is better than a straight shot to the tank, and that’s true. That same fuel tank design one could simply pull the trigger and fill the tank without burping on a 1988 Pantera II or Sabre.

Over years several things changed which made filling any tank a challenge. The first factor is the type of fuel additives. Even those 1988 model fuel tanks one could pull the trigger and walk away from no longer fill like they did in 1988. While that was 31 years ago, some more mature Bass Cat Owners here today will remember this wonderful experience as they read this. It truly was (1988 design) a breath of fresh air thing for those fueling our boats over others, that were always a problem before. Thus the fuel and pump sensing are the only two items that changed to effect a 1988 model.

Probably the most impactful of today’s problems and what makes all go reaching for solutions is the change in fuel additives. It’s a typical example of causing a problem while trying to improve another. Another example of one engineer not realizing they might have created more VOC’s escaping, or a larger carbon footprint, while reducing the one they were targeting. Think gas can here as mentioned above. They tried to reduce emissions, though most make a huge mess trying to use these environmentally friendly gas cans. Thus emissions most likely were increased in an effort to reduce them. Bureaucracy at work?

There are two things on a newer boat after about 2012 to look at, one is angle of the fill nozzle, and the other is a restriction possible inside the tank from the interior lining. These are our controllable factors.

In recent years there is a requirement for a non permeable lining, this prevents vapors from leaking through the plastic tank walls. That lining has in some isolated cases had an interior lip that restricts the fuel from entering the tank on extremely few fuel tanks. We are talking single digit incidents where those are not caught at BCB. Look directly down into the fuel cap with an LED light and see if you notice a red nozzle and a clean path through that red insert to the fuel tank. You will have to hold open the Perko flapper valve insert that prevents fuel escaping and it is spring loaded. This makes this a two handed process with some form of a longer probe to open the flapper. The red insert will be forced closed or not have a clean path if the tank liner is restricting it. These should be caught easily at BCB as we install the reed insert outside the boat, thus very few have escaped. It is a problem at the tank manufacturer which escaped their detection, then we make that same error. In those cases newer staff usually just doesn’t understand it critical to have the neck totally open.

The other is the right angle on filling as with your vehicle the pump nozzles are design curved purposely, as you almost always are forcing fuel down on a path into a bend. In the case of your boat it is going into a straight path. This requires a contortion of the fill nozzle to get the pressures right on their equipment sensors. It also needs that fuel path to create a similar path regarding the way the fuel is designed to flow in their equipment and thus ours. Which leads to why some angles fill easier. Your truck fill is a continuance of the curve created by the hose and handle to nozzle configuration.

*Tractor Supply has a neat little part (hose) in its home and garden section that allows you to extend the fuel nozzle for different operations, where one can reach a tank. While it’s highly against EPA regulations to use this to avoid the government shut switches, and sensitivity that fuel pumps have, what do you think it’s really for?

Today’s fuel tanks on Bass Cat have pressurized sealed systems of up to 1 pound, which can extend pressure to almost 2 Pounds in some valves we have seen. Those vents are located inside the cap itself.

The 2012 and later tanks have fuel demand valves and FLVV systems to keep a percentage of tank space as an air level inside the tank. The limit is around 4% opacity in air. Most valves (FLVV) today are set at 7% as a safety gap by the equipment engineers. They have modeling software which selects the particular parts and levels. It’s not simple venting anymore. Hoses must not have any kinks in them as the air will trap inside those and the system will absolutely fail. They also have a limit as to how much sag any hose can have as the system being under pressure will not allow the fuel to move inside its own vessel. Thus is a hose is trapping air, that sump traps fuel in the hose and prevents air from flowing through the internal tank system.

The Perko insert inside the hose is a moving part, or flapper like on a vehicle, that is spring loaded. While extremely rare, we could have place that valve in backwards. Doubtful this is the case on a used or older boat, as someone should have caught it before now as those tanks will absolutely not fill.

One more note to make extends back to about 2002, when Bass Cat began using an anti siphon valve. While this is not required for a boat with situations where the engine aspiration (carbs or injectors) is higher than the tank, it is required today in some areas for storage inside you home. This relates to NFPA codes for fire protection. Yep, another government opinion on preventing fuel from siphoning out on your garage floor. Simply trying to be redundant on protection as there are those that had this issue in their inboard designs. The tanks would siphon in through the carbs and flow out when not in use.

We aren’t getting into the carbon canister systems, though we do use that system on Yar-Craft because they have multiple engines for trolling. Other bass boat companies began with canister systems and had atrocious problems with them in a compact bass boat. Many of those have many switched to the pressure systems we have now.

That’s the short, and the long on today’s fuel systems. We sure enjoyed the way a 1988 Pantera II filled.