Powder coating a new fuel tank

[wwheeler]

I seem to recall reading a recent post (can't find it now) indicating that the fuel tanks have a plastic flower pot. If this is this case, you can't powder coat them. The flower pot pictures in the tech manual look as though it is metal. Possibly the new MB replacements are plastic?

Does anybody know if it is possible to powder coat a new fuel tank?

[DavidBrough]

I've had mine powder coated but that was before I read the post about plastic flower pots. I haven't got round to refitting it yet as I've only just repatriated the bodyshell from the repairers. I've had a good look inside the tank as far as I can and it does look OK but won't really be able to tell untill it's in and working, or not.

[mdsalemi]

Having a lot of experience with my local powder coater (Exotic Coatings; those who attended PUB found their brochure on their front seat  I can suggest that powder coating OUR fuel tank would be dicey business.

Anything that holds fluid or pressure and gets PC must obviously come out of the process still able to hold its contents.  The long baking process can "open up" all kinds of issues, and if that happens, now you have a part that needs repair and refinishing.  That makes a very expensive part--our fuel tank--even more costly.

I believe that the flower pot is plastic; in the tech manual the plastic would be discolored.  You'd be discolored too, sitting in petrol all your life.  Even if earlier ones might be metal, if they are zinc they might not survive the baking.

My suggestion is to leave the powder coating for passive parts.  The fuel tank is active.  It might cost $200 or more to coat it anyway, and that's a big investment in an already expensive part.  A good, solid paint job will last a very long time and give you no potential issues.

[wwheeler]

Good observations! I am also a little worried about the fuel lines coming out of the tank. How are they sealed to the tank? Probably best to go the paint route and not risk messing up a very expensive part.

[mdsalemi]

Because the tank is steel, lines coming out, or more properly, fittings for lines, they are probably brazed or welded in.  Brazing and welding can generally survive powder coating; soldering generally can not.

In a previous post I related my experience with the coolant overflow tank.  When others here told me that they had theirs powder coated successfully, I began the process.  After stripping and a pre-bake, solder flowed out of all the joints, compromising the tank.  Perforations showed up in places you would not have expected.  The powder coater rejected the tank for further work.  I then had to have it repaired and tested ($80) prior to conventional repainting.  An expensive and time consuming lesson.