Home › Forums › Bass Cat Boats › Fuel tank pressure too high?
The driver side fuel tank in my new Lynx is swelling out of shape. Even after I relieve the pressure when I open the filler cap it holds this bloated looking form. It is bulging on the top and sides. The top is about 3/4 of an inch higher than the outside corners. The passenger side only has minor bulging, less than 1/4 inch. I don’t recall my Caracal having this happen. Thoughts??


The caps are designed to release at 1 pound roughly. The fuel caps could be popped and left slightly loose and relieve the pressure though we are not sure at this time what else to suggest. These are Moeller tanks with Attwood fill caps. The entire system depends on EPA approved parts and these are e same parts as your Caracal.
doing some investigation.
Reach out to matt Hayes on FB. He found a solution to this.
Something tells me 1lb of pressure is not enough to stretch out a fuel tank like this. Something must be wrong and it concerns me something could fail. Opening the cap while on the lake is not a realistic solution. Please help resolve this BCB!!
The compression on the release will expand the tanks with one pound. Two pounds makes them a balloon. We will discuss this further with Service.
One pound in that much volume/plastic can balloon that tank.
The float bags on our aircraft expand from a 3000 psi nitrogen bottle. Blows them tight to a total of 3lbs. One more pound and they blow apart.
Still seems like the relief valve on your tank may be keeping a bit more pressure than it should. Keep in mind it would only take a 1/2 pound of pressure more than it should to make that tank ugly. Hopefully BCB can pinpoint the issue
Don
Im having a similar problem on my 2020 puma. Both tanks are difficult to fill and swell just like your Lynx. I can hear them slowly letting off pressure around the fill caps. Open them up and there is a large gush of fumes as the tanks decompress. Did you ever find a fix?
We REALLY appreciate you doing a search here and finding a similar inquiry. The situation is one that the newer EPA tanks hold up to 1 pound of pressure. Mr Hayes likely can assist you also.
Cumberlandcat
I see you have two posts related to this so I’ll respond here since I started the thread. I admit I am a little puzzled by the varying responses BCB offered between the two threads. The one in the other thread commenting on legality tells the story while in this thread they acknowledge Mr Hayes can assist. My experience as well as others I have come in contact with is that there seems to be an inconsistency with how the fuel systems are handling the EPA required pressure/venting. As I said, my Caracal did not have the same rather extreme tank bloating in my Lynx tanks. Even one of my Lynx tanks is visibly more affected than the other.
So I can only offer my opinion that in my experience and communication with others inconsistencies exist.
Bottom line is neither BCB nor any other manufacturer, including Moeller (tanks) or Attwood (venting/gas caps) will offer a workaround at the peril of violating EPA regs. It is frustrating to have to basically be told it is all “normal”. Without proper testing the system it cannot be proven it is malfunctioning. As long as it holds back the required minimum pressure any excess is apparently OK. The crazy thing is when you open the gas cap it blows off into the atmosphere anyway.
The workaround inferred above by the reference to “Mr Hayes” involves the gas cap and it does work. The question I suppose for BCB is, as they understand what is being done here, is there any risk other than EPA regs? I do not know what risk owners face legally but I have never had a or heard of bass boats being testing in the field by state or federal agencies like cars. Maybe CA does this? It is a personal decision in the absence of true product testing but would be nice to understand the risks.
No Comment… We can’t
Did you find a fix for your tank? Someone had commented to reach out to me on face book ( Matt Hayes). I spoke with someone the other day about the issue not sure if it was the OP or not. Pm me on here and I can walk you though a pretty simple partial fix.
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