Plastic Fuel Tank Coating

[LBC Tenni]

My 2014 Norge is about to get its 3rd tank, prior 2 presumably deformed by reaction with ethanol. Caswell claims their coating will adhere to plastic. Anyone have experience or a better idea?
Thanks
Don

[Triple Jim]

I know that Caswell's Phenol Novolac epoxy liner sticks to the polyester resin in the fiberglass of tanks a friend of mine manufactures.  You might talk to a technical support guy at Caswell, give him the specifics, and see if he has any recommendations.  Do you know what plastic the tank is made of?

[lucian]

It works well to protect plastic tanks from ethanol if you prep them properly. If the tank has seen gas it will need to be aired out for a long period
 in a warm dry place. My dealership does Ducati and Aprilia tanks for customers during  the winter storage period. They drain and flush the tanks and leave them on top of a hot air duct for the heating system for at least a couple months.
You would think the tank manufactures would have addressed this problem by now. Especially considering how many second and third tanks they have had to dish out under warranties.

[Chuck in Indiana]

I fixed an "unfixable" Quota tank with Caswells epoxy, and a Rosso Corsa..
http://wildguzzi.com/forum/index.php?topic=62087.10;wap2

Edit: I see this is in the archives, now, so no pictures. Sorry..

[lucian]

Just found this on the lemans site




http://www.v11lemans.com/forums/index.php?showtopic=16928

[Triple Jim]

Just found this on the lemans site

That's the very reason I suggested talking to a tech support guy at Caswell, and asked if the material the tank is made of is known.  I wouldn't try putting epoxy on an unknown material.  Nylon was mentioned the Lemans thread, and I doubt if epoxy will stick to Nylon no matter what you do to it.  Same with polyethylene.

[LBC Tenni]

I think I read somewhere that the Norge tank is nylon? Not sure.

[averb]

The Norge, Breva, Sport tanks are Nylon 6

[Triple Jim]

The Norge, Breva, Sport tanks are Nylon 6

Excellent,  now there's enough information to be able to talk to the Caswell guy, as well as do some independent research.

Edit: Like this, for example:  http://archive.plasticsdecorating.com/ENEWS/ENews.asp?item=101812qa-sabreen

[Buckturgidson]

My Ducati tank was replaced under warranty 5 years ago. I put Caswell in the new tank, no problems.

[leolad]

My Ducati tank was replaced under warranty 5 years ago. I put Caswell in the new tank, no problems.

Same for me. There is a guy on the Ducati.ms site that has a service to coat tanks. They use a rotisserie and deck screws to score the tank, then they cost with Caswell.

[britman]

I spent most yesterday replacing fuel lines on my chainsaw and weed eater.  I do like alcohol but from now on I am avoiding it in all of my small engines and old bikes.  There is a corn free pump a few miles further away with a higher price, but it is on the menu from now on...........

[LBC Tenni]

It's now impossible to get corn free gas in CA for less than $10 per gallon. Corn crooks have screwed us completely. I'll check that service on the Duc forum. Thanks.

[Rusnak_322]

My Ducati Monster had a new replacement tank coated with Caswell at a dealership before any gas was put in.
A few years later it peeled off in chunks. Zero damage to the tank that could of / would of led to the failure.







My third tank is now expanded to the point that I cannot latch it anymore. Other than boat docks, there isn't any alcohol free gas around me.

[Rusnak_322]

BTW: a couple of years ago, when working at a company that produced fiberglass fans and air pollution control equipment for use in corrosive environments, I had the head of a major resin manufacture's R&D lab in to help us solve some issues we were having. At the time I was making a fiberglass seat for my café racer and wanted to make a custom tank as well. I asked him about what resins or types of coatings I could use and he said that there was nothing that could withstand the alcohol in the gas short of a bladder type liner.   

[EldoMike]

I've heard vinyl-ester tanks withstand the effects of corn fuel...anybody have experience with it?

[averb]

From http://archive.plasticsdecorating.com/ENEWS/ENews.asp?item=101812qa-sabreen listed above

"Further, nylons are hygroscopic and will absorb moisture in excess of three percent of its mass of water from the atmosphere. Moisture, in and of itself, creates adhesion problems. The rate of moisture absorption is dependent upon time, relative humidity and temperature. Therefore, it is important to perform bonding processes as soon as possible following molding operations or package the parts tightly in non-poly bags with a desiccant"

The reason the Nylon tanks bulge is because they absorb moisture. The reason the moisture is there is because the alcohol attracts the water molecules, which normally isn't a problem but when it is left sitting the moisture separates out and is available for the Nylon to absorb. Theoretically, if you use your bike constantly and/or don't leave it sitting with a full fuel tank you shouldn't suffer from this problem. I say theoretically because I haven't had the problem in either of my plastic tank Guzzis but I don't know if it is because of the way they are used or maintained.

Also if you tank does suffer from bulging you can reverse it by drying it out as described above. This may be impractical but if for example you have a non-riding season you could always take the opportunity give a try.

Steve 

[LBC Tenni]

Thanks all. Lots of good info.