have 1967 bsa spitfire mk3 just did total restoration better then new having trouble with leaking fiberglass tank looking for imformation is anybody reproduceing the yet or does anybody have a good used one
jhny: This gets discussed quite a bit because many of them leak now. One place I've seen new ones is on the Burton's Bike Bits website. I think a guy in Australia has built some, and another guy in Michigan has talked about it. If tank is already leaking, some would recommend Caswell epoxy sealer. It might depend on what has already been applied in the tank in the past.
I've also read diccussions of cutting the tank apart to repair from inside, but I haven't gone this far. I have just given up on a 66 tank which was disintegrating inside.
These tanks are often on eBay, kind of a crapshoot, but I just got a good one. British Only has them used on their site, very expensive.
There are many other sealers: Kreem is kind of in disrepute, but there are Hirsch, POR15 and others, and some in the aviation field. Don't know how well these could work in a tank already leaking.
#10127 - 04/16/067:57 pmRe: 1967 bsa fiberglass fuel tank
Is the tank leaking at the seam where the bottom is bonded to the main tank? Or is it leaking through the walls of the tank?
There is a lot of controversy on fiberglass for fuel tanks. The vintage BSA tanks probably have suspect epoxy holding the bottom/tank together. The epoxies used then are suspect with today's gas. If it is leaking through the walls of the tank, it has either been repaired or was not properly made originally. Fiberglass fuel tanks rely on a coating of resin to keep the fuel away from the glass fiber. Once the fuel gets in the fiber, the fiber swells, breaking the surrounding resin...good bye fuel tank.
Making a new tank is possible. It requires a knowledge of resins, laying glass cloth, etc. The critical part of making fuel tanks is the proper layering of resins to make the tank seal and prevent fuel soaking of the glass mat.
And no, I don't make tanks. But work closely with a fiberglass supplier at work who does as a sideline (for stationary engine restoration). I have already asked if he would be interested in making new BSA tanks. To date..the answer is no. Cost of new molds and volume will make them too expensive to be viable.
Life is too short to drink cheap, bad beer.
#10131 - 04/21/063:13 amRe: 1967 bsa fiberglass fuel tank
Joined: Jan 2006 Posts: 3,317Gary E
BritBike Forum member
Try using aviation tank sloshing compound sealer. There are a number of them available.
I built a Lancair which is a high performance all composite experimental aircraft and used fiberglass and epoxies for over 10 years during the building process. This aircraft, since it is all composite has composite wings, thus composite fuel tanks. These tanks get tank sealer put in them. I have never had a leak. (the disclaimer is avgas doesn't have the crap additives like auto fuel has)
When sloshing your tank, if you know where the leak (or leaks) are, put a vacum cleaner hose to the spot on the outside so it creates a suction for the sloshing compund to be drawn in to the leak area. Really clean the inside first with a thinner. Do a test on something first to see what the thinner does. Some thinners will really soften polyester or vinylester resins (boat glass) but will dry and harden.
I run avgas in my Firebird Scrambler and Hornet (glass tanks). No leaks yet. Plus that 10.5 to 1 compression likes it.
1967 BSA Wasp 1967 BSA Hornet (West Coast Model) 1967 BSA Hornet (East Coast Model) 1968 BSA Firebird Scrambler 1968 BSA Spitfire Mark IV