TOPIC: Tank Funk

The fuel tank in my Formula 223 SS had about an inch of "fuel funk" in the bottom. It's caused me to be stranded twice due to plugging up the canister fuel filter. A new one was $968.00. A poly tank that was smaller but would do the job was $650. Removing the tank which is embedded with foam would have been a major job. The tank is made of 1/8" aluminum so I decided to perform major surgery.

We drained the tank then filled it to the top with water. Then I marked-out and cut three 12"x12" squares between the baffles. After that, we drained the tank and scooped out all the funk with a 3" putty knife. We filled a quart container with it. The tank was then cleaned with purple power and wiped-out with acetone.

I covered the cut-outs with 14"x14"x1/8" aluminum plates held down with #8 sheetmetal screws placed every inch and Permatex silicon to seal them. We lake-tested the boat today. Ran great, zero leaks.

Looks like you found a way to save a thousand dollars!

Just FYI, Permatex Silicone is NOT fuel resistant. Per their FAQ section on their website:


Can I use the Permatex® Ultra Blue® RTV to seal a gas gauge-sending unit to a gas tank?
-
No, Ultra Blue® is a silicone-based product, that will offer a good seal, and has good resistance to oil and coolant, however, silicones are not recommended for use in a gasoline environment. The gasoline will attack the product. Permatex® offers the solvent based Form-A-Gasket® products or MotoSeal® #29132 [hyperlink to 29132 product page] that are designed for applications in a gasoline environment.


Where would you use the Aviation Form-A-Gasket® No.3 Sealant?
-
The Aviation Form-A-Gasket is a slow drying, non-hardening, sealant, resists gasoline, oil and grease. It is used for close-fitting machined surfaces, sealing hoses and solid gaskets.


I'd hate to hear about you and your family blowing up, because you used the wrong stuff.

I didn't use the wrong stuff. I used the wrong word. Permatex Form-a-gasket is what we used, not silicon. We had just used silicon to install a new vent fitting so I guess I had silicon on the brain. Sorry for sounding like an idiot.

Excellent, thanks saved a few bucks!

Bob

Good info. Should work on old steel tanks also.

Nautilus wrote:

I didn't use the wrong stuff. I used the wrong word. Permatex Form-a-gasket is what we used, not silicon. We had just used silicon to install a new vent fitting so I guess I had silicon on the brain. Sorry for sounding like an idiot.

No worries, just wanted to make sure you and the family are safe and have fun.

FYI, SEAFOAM, is an excellent gas tank cleaner. For a Large tank such as described above, adding a $9.00 bottle of it and 5 gallons of gas to the tank and then taking a ride with the boat hooked to the trailer for some agitation a couple of times over a period of a week or so and then pump it out. You'll be amazed how it will melt away the gunk in tanks.