Still working on gas tank leak

[Matt Hayes]

Theres an o ring on the attwood fuel demand valve then another below it for the siphon tube. I would also ensure that the brass fitting going into the valve on top of the tank did not crack it from over tightening. I will send you a pm if we have not already talked about a possible fuel tank swelling remedy- Matt

[BillBo]

Thanks, Matt. I am aware of the fix(es) for the swelling. I assume that BCB experts have not responded yet as they are busy supporting their MLF pros up in Wisconsin. I am not the greatest with mechanical stuff, but given instructions I can usually make a repair without causing harm to the components.

First I am trying to understand if the looseness is reason to suspect an issue with the valve assembly. What would cause that assembly to be loose?  How does one tighten it? The forked retaining clip doesn’t seem to do anything as far as I can tell.  It would be helpful to see a diagram of the assembly above and below the tank top and how that assembly fits into the tank. Yes, the leak may be around the o-ring, but replacing the o-ring does not seem to be the cure if the assembly is not tight with the tank.  As I said, there is no play at all with the valve on the other tank.

The “repair” kit I received from BCB consists simply of a large washer with a rubber gasket, the large aluminum retaining nut, and a tube of gasoline compatible sealant. The only instructions given were for replacing the existing nut with the washer and nut and using the sealant. That alone would not seem to correct the problem if the leak is around that o-ring and due to the looseness of the assembly.  Perhaps the kit was supplied with the idea that the corrective measure involves removing that large nut and then somehow tightening the assembly from underneath, then replacing the nut and using the gasketed washer. The present aluminum nut is very tight on the tank so I hesitate to try to crack that loose without understanding what causes the assembly to be loose and how it can be tightened.

Best,

Bill B.

 

[SLumpp]

I went through a similar situation on my Cougar.  I could drive it all day long on the drivers side tank, however the boat would not come up on plane, nor run at all sometimes on the passenger side tank.  I finally figured it out that mine was a problem with the valve assembly, as it was leaking through the top that was broken.  The only way that I figured that out was to flip the switch to that tank, and then squeeze the bulb.  On mine the bulb was mushy, would not stay hard, and then showed me the leak out the top.  I took mine off via the fork that holds it in place, unscrewed the brass fitting, wrapped the threads with the yellow Teflon tape (for gas products and no more than 2 times around),  and sealed it up.  I have had no leaks, no problems since then.  That gas actuator valve will not work properly if there is any kind of air leak.  I would suggest try squeezing the bulb next time you are out there with the switch changed to the proper tank to see if you can visually see where any leak is coming from.  Good luck with this repair.

[BillBo]

SLumpp, Thanks for the suggestion. I hope to get back to the boat later this week.  I will try pressuring that tank with the bulb. However, I think mine is only leaking when the tank is fairly full and gets under pressure. And the boat seems to run fine on that tank so far.  But of course having fuel spit out into the bilge is never good.  Another suggestion said to try bending the “E” retaining clip slightly, which evidently is the only thing that keeps the valve assembly/O-ring firmly in place. There seems to be some play up and down around the E clip.

[Bass Cat Boats]

They have a kit to repair these tanks in the Service Department. They just need your serial number to send one out.

[BillBo]

Bass Cat Boats:

They have a kit to repair these tanks in the Service Department. They just need your serial number to send one out.

Thanks, BCB. Per first post, I already received that kit, but as stated I hesitate to go that route as I do not think it will solve the problem. I guess might need to pressure test the tank to determine exact source of leak. But clearly its around the base of that assembly or around the large O-ring above the top of tank.

[Bass Cat Boats]

The kit is the solution with the sealant.

[catdude28]

BCB, is the sealant part of the kit?  I only received the valve only with mine. Nothing else.

[Bass Cat Boats]

The kit has a metal washer and sealant, the valve is not in the kit. If the tank Fuel Demand valve is cracked or broken then that is a different situation.

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