JB Weld or?

[saltshaker]

Ok so not a boat question but thought I might get some insight here. The fill next for the fuel tank on one of my snowmobiles is cracked at the base. Any thoughts as to what I can use to fix it until I get a chance
To replace the tank? Changing the tank is a big PITA and the sleds are about 4 hours from home. Hoping to be able to fix it with something like JB Weld. The crack is at the base of the fill neck. I have about 3/8 space from the base to the bottom of the cap.

 

[SEVEN]

Not sure I would use JB Weld because it drys hard. With the vibration a snow mobile gets I would use a flexible caulking that has a fuel resistants. I used one on a heat exchanger that was resistant to coolant. It was orange in color. Not paintable but it worked. Go to any auto parts store and look at all of their heat and fuel resistant caulking. You're sure to find one that will work. Good hunting. T

 

[krush]

rescue tape...the self sticking silcon stuff or something similar

 

[rwappleton]

Jack, If the neck is plastic JB weld wont work. If it is metal clean it good and rock on! Russ

 

[BOATER BOB]

They make a radiator repair kit for cars and it just fiberglass cloth and epoxy try that for your tank.
Bob

 

[Boatsb]

Bubble gum.

It's cold. It won't soften if it sticks.

 

[dottieshusband]

Aircraft Spruce sells several kits that would work. I used some black polysulfide to fix an aircraft tank leak. 15 years later, I'm still trying to get it off my hands!

 

[saltshaker]

Thanks all it is plastic not metal and yes vibration is a concern. If I can get through the next weekend I'll be fine as I can replace the tank after that. Paul what was the tank material you repaired?

 

[MikeP]

I have personally seen JB Weld do some amazing stuff. One repair on a transmission over 20 years ago as a "temporary fix" is still the ONLY fix. OTOH, I have to admit that I don't know about its longevity with plastic though I have used it on plastic parts that are still solid after 2-3 years.

JB Weld is, IMO, in the "required item" toolbox along with WD40 and Duck Tape!

 

[jim rosenthal]

Jack, Pettit used to make a stuff called Flexpoxy which is a two-part resin that cures to be flexible. It will stick to plastic if it is dry and sanded and doesn't have silicone residue on it. Try that. I think they still make it.

 

[Outfitter]

Get some fast cure 4200 3M caulk. I wish I would of bought stock in the 4200 & 5200. I've glued shit on my 4 wheeler, truck, boats, ect. I usually use the blk 5200 which is pretty permanent stuff. But it holds up pretty good around fuel &dirty environments.

Zak K.
53C Black Hat Affair

 

[bobk]

Thanks all it is plastic not metal and yes vibration is a concern. If I can get through the next weekend I'll be fine as I can replace the tank after that. Paul what was the tank material you repaired?

Plastic fuel tanks are usually made from a polyolefin; think about the jerry fuel cans. Not much will stick to a polyolefin without an ionizing pretreatment. If this is a potential hazard, I'd fix it properly and not risk a fire in a remote area.

Good luck,
Bobk

 

[saltshaker]

Plastic fuel tanks are usually made from a polyolefin; think about the jerry fuel cans. Not much will stick to a polyolefin without an ionizing pretreatment. If this is a potential hazard, I'd fix it properly and not risk a fire in a remote area.

Good luck,
Bobk

Thanks Bob. It's only an issue when the tank is 7/8 full or higher as the crack is in the fill neck. The tank itself does not leak other than at the fill. Even then it only leaks a small amount. I'm planning on replacing the tank but as I mentioned earlier, I can't get to it right away.

 

[madhatter1]

Motocross bikes are my second hobby and the kids kill me with things they break. So I have become a JB weld artist. I have fabricated lever ends as well as fixed busted engine cases. Very strong stuff but the engine case repairs while holding up great leak enough oil that I can see dirt accumulation from it. So you may leak a tiny bit of fuel depending on location of repair. On a sled, like our bikes, probably OK. Going to seal a small crack in a case where a bolt backed out of the crank later this week. A little Frankenstein but dang those case halves are expensive.

Don't get me started on whet we fixed with duct tape! And that worked too.

 

[MikeP]

I have seen JB Weld seal holes/cracks in transmissions and to hold bearings in place where the outer race had spun in the carrier...that are still holding after 20 years so I'm a fan. In fact, several of the particular instancesI'm thinking about were done to hold temporarily until the parts were replaced...but they never were!

 

[spartonboat1]

If you do have plastic substrate to repair, there is a true industrial grade plastic adhesive called 3M DP8005, that is a serious glue. It may not be sold as DP8010, but here is a link.

You buy a double sided tube, an applicator gun and a package of applicator tips. It requires a new tip for each application. If you can't find it locally (usually industrial adhesive houses will have it), I think Amazon has it.

http://multimedia.3m.com/mws/media/209848O/cj766-uk-dp8005-brochure.PDF

3M 5200 is also very serious, but requires 24+ hours to setup. Then it will never come apart. Stronger than 4200 variants.

 

[bobk]

If you do have plastic substrate to repair, there is a true industrial grade plastic adhesive called 3M DP8005, that is a serious glue. It may not be sold as DP8010, but here is a link.

You buy a double sided tube, an applicator gun and a package of applicator tips. It requires a new tip for each application. If you can't find it locally (usually industrial adhesive houses will have it), I think Amazon has it.

http://multimedia.3m.com/mws/media/209848O/cj766-uk-dp8005-brochure.PDF

3M 5200 is also very serious, but requires 24+ hours to setup. Then it will never come apart. Stronger than 4200 variants.

Thanks for this. Impressive stuff, but look at the effect on petrol and toluene. They markedly reduce cohesive failure. Might still make a patch though.

Bobk

 

[MikeP]

Re solvents...

FWIW JB Weld is commonly used to permanently seal the casting plugs on old Quadrajet carbs. Doing this is a "must do" on an original QJ for performance work because they pretty much ALL leaked internally, which screwed up the mixture, and also eventually leaked externally. Anyway, that is another repair example I have seen that in many cases were done decades ago with JBW and still working fine in a "submerged in gasoline" environment.

 

[saltshaker]

I used JB Weld and it seems to have bonded well. This is a fairly common problem and others have cut a piece of PVC and sleeved the fill neck. I'm thinking a piece of fuel hose fit snug in the neck may be enough to add strength and get me through the season. If I can wait til spring to tear down the seat and replace the tank with a new one, that would be ideal. Season is short and we want to get as much ride time in as possible. We rarely use the car when up there. More fun to run to the store or out to dinner on a sled. Been a great season so far as we've had good snow every weekend since the trails opened on 12/10.

 

[saltshaker]

Thought I'd post an update on this. JB Weld held up great so far. We were out Sat, Sun and Monday and no more leak. Didn't realize how bad the leak was before. I think I lost at least 1-1.5gls when the tank was near full. Track got stuck so I had to turn the sled on its side to free up the track. Not a drop of fuel leaked out.