Fuel TAnk leak

[Tom Utesch]

I've got a 1982 in very nice shape... except for the fuel tank leak. Seems to be leaking along the bottom seam near the petcock. A bit of rust is showing through the paint at the seam as well. I checked with my local honda dealer and although they still show a new tank, none are apparently available. So... solutions gentlemen? I expect it is too far gone to use any of the tank sealers.



Thanks for your help.

[Carl]

Ebay.com of course...

[RIPPER]

www.por-15.com

[Blaine McKibbin]

Same thing happened to a CB550 I was resuscitating several years ago. Tiny pin hole leak on the petcock side of the tank. The leak came through on the side panel of the tank where side panel meets the bottom panel. There is a convenient groove in there, where the panels meet, for the moisture (gas tank terrorists) to accumulate and plan its's attack on the metal of your tank. The leak appeared the first time I filled the tank after repainting it so I was not hesitant about trying to repair it. I repaired it with JB Weld (or some other similar epoxy glue). I first used progressively larger drill bits to drill out the hole until I was satisfied that there was enough metal around the perimeter of the hole to be sturdy and allow the epoxy adequate purchase. The hole ended up being about 2mm high and 3mm long. I used some sort of long sharp rod to scrape and clean the rust from the groove on the inside of the tank. When I was satisfied that the removable rust had been removed I applied the epoxy through the hole from the outside and let it run on the inside of the tank around the perimeter of the hole. The epoxy is quite runny at this stage, so until it "kicks off" and hardens you should put a piece of masking tape over the outside of the hole to prevent the epoxy from running out and gluing your tank to the table or floor. Tip the tank partly onto its side so that the hole is on the bottom and the epoxy in the tank is able to form a little puddle around the hole on the inside of the tank. Wait 24 hrs for the epoxy to cure. This method worked for me. It has been 3 years and the patch is still holding. I touched up the outside of the tank and repair is noticable only because I left a tiny bit of extra epoxy on the lower edge of the hole on the outside of the tank. I have never used a tank repair kit, but I understand that it is just epoxy resin that lines the entire inside of the tank. If you plan to do the repair and consider the bike a "keeper", I suggest you use the kit also. Good luck and have fun.



Blaine

[Dave Ditner]

One of the things that I do to prevent this problem is when going into cold storage for Michigan winters is to put a can of drygas in the tank, then fill it to the brim. Shut off the fuel and run the carbs bone dry, including the accelerator pumps. Leave it until spring. The drygas will absorb any moisture that should occur during the winter. Springtime gets a bottle of fuel injector cleaner as soon as there's room for it in the tank

For hot storage, like leaving my bike in a shed in Florida during the summer, everything gets drained, tank and carbs, then I pull the tank, put a little oil in it roll it around to thoroughly coat the interior, then reinstall it, hook up the fuel line and it's ready for fall.

The reason for the two different schemes is that fuel volatility varys greatly from summer to winter. It is measured by a property called the Reed Vapor Pressure. More light ends are in winter fuel than summer fuel to allow for easy starting in cold weather. Fewer light ends are in summer fuel to try to prevent vapor lock. A higher vapor pressure means that th fuel will evaporate easier. So it's fairly easy to see why summer fuel will winter with no problem, but winter fuel will evaporate easily in the summer leaving much to be desired in the tank and carbs