Lorenzo, Pat, or any of you guys with the new NF plastic tanks. Have you been having any trouble with the foam gaskit on the tank filler cap leaking air? Just wondering. It takes forever to get fuel into the carb on my bike, and I can blow into the suction line on the pipe and air leaks out around the filler cap. I also think it's responsible for the erratic running I've had the last few times out. Cheap crap. Guess I'll have to get something to make a rubber gaskit out of.

Originally Posted by mollycbr123

Lorenzo, Pat, or any of you guys with the new NF plastic tanks. Have you been having any trouble with the foam gaskit on the tank filler cap leaking air? Just wondering. It takes forever to get fuel into the carb on my bike, and I can blow into the suction line on the pipe and air leaks out around the filler cap. I also think it's responsible for the erratic running I've had the last few times out. Cheap crap. Guess I'll have to get something to make a rubber gaskit out of.

Hey Steve,

Wish I could help you out ... but I guess I must have picked up the NF just as the plastic was coming in ... I got lucky and received the aluminium tank with mine.

Pat

The best way to get fuel into the carb is to pinch the over-flow
fuel line and then blow directly into the exhaust pipe, while pinching
the tube. The fuel will flow really fast right into the carb so watch
it. Your just blowing on the wrong end...

Lorenzo

That's what I've ended up doing, Lorenzo. I've also just blown into the pressure line itself, while holding pressure down on the tank filler cap to keep it sealed. But it sure is hard to tell when you've got enough fuel into the carb either way.

The first few times I ran the bike and primed the carb, you could just watch the fuel go right up the line into the carb with just a few spins on the engine. Nice. Now it won't do it. I guess I'm really more concerned about how the leak will affect fuel delivery when the bike is running. It seems to keep quite a bit of air in the fuel line now, and cuts out more frequently. I've checked all the lines, and no leaks that I can see. Just wondering if anyone else seemed to be having any trouble with the new "upgraded" NF tank?

STeve B in NC

Well, I was having problems with the fuel tubing leaking, which is
connected directly to the center of the tank. I pulled the tank off
which took just a minute and installed a fresh fuel line and the
problem went away.

If you are still having problem, maybe you should just replace all
the fuel lines and I'll bet this will fix the problem. The seal on
gas tank doesn't need to be super tight so you are probably
sucking air from some other location. It's really pretty simple
to replace the lines so I would do that first and then try again?

Lorenzo

Well it's got to be one way or the other. If the tank was sealed fine, the air and fuel in the tank and fuel in the tube to carb would always be under pressure. Some guys have had problems with too much pressure, causing air from the pipe to be forced into the fuel, causing aeration. I've heard of 2 guys who have restricted the pressure pipe to stop this.
On the other hand, if the tank is not sealing at all, the tank will not get pressurised and the carb will cause negative pressure in the fuel line to suck fuel in. (this will also put the mixture out) So, as Lorenzo says, if the fuel line has a tiny split, anywhere, air can get sucked in. It's a good idea to replace the silicone tubes before looking anywhere else. And that tank has to have a good seal to have reliable running.

John