I bought a 1997 MXZ 670 this summer - my first snowmobile; intend to (and have) start it up every week or so to let it run, so I topped off the fuel tank - filled it right to to the top.

It leaked out the bottom so that it is now "full" based on the fuel cap indicator (the float gauge).

It has not dropped below the "full" mark on the gauge (so it is not leaking anymore)

I can't find anything in the manual regarding overflow; previous owner said that it never leaked that he was aware of.

My question is - is this okay? Is the fuel tank designed so that anything above the full mark on the gauge is "overfill" and will drain out? Just seems odd.

Thanks

seville, the reson you had a fuel leak is that the fuel will expand in the warm weather. If you tank was full, the excess fuel would have been forced out the overflow.

Thanks for the reply.

It leaked out as soon as I filled it though and pretty quick, so I don't think that it was because it was of the heat, but I could be wrong.

I didn't see it leaking, so I'm not sure where it was actually coming from on the tank. I had it parked next to the house and could smell the gas through the window. I thought that it was because I had just filled it and had just run the engine for a little bit, but when I moved it the next day, there was a foot diameter burn spot in the grass from where the gas hit, and I saw that the fuel in the tank was down to the full mark (instead of the bottom of the filler next which is where I filled it to).

I just want to make sure that the tank itself is not leaking; that somehow it is just doing what it is designed to do. I could not see in the manual where the overflow would be.

I have the same sled and if I remember the vent is not at the very top of the tank.
It is down a little bit from the filler. On your "handle steering support" as it is called in the parts catalog their is the vent line for the tank near the filler.. It goes out one way down near your foot and back up over to the other foot well. The handle s s is a tube that connects to the tunnel on each side. The front of your gas tank is underneath it and all the plastic is attached. If you loosen the center piece of plastic you should be able to see the vent line, 1/4" clear tubing. To take it off you have to pull the handlbars off. Mine always dropped a little but I never remember seeing a gas puddle. You can see this tube near your starter rope if you pop the hood open. Look for gas in the line and make sure it is connected to the fitting that goes into the tank. That fitting also goes into a rubber bushing that "seals" the tank. Hope this helps and hope you enjoy your 670.

Team Old Iron;

Thanks for the details; I'll have to take a look at the line to see where it's
coming into the tank. I think everything's okay (ie: not really a leak) just because it seems odd that the leak would "stop" right at the "full' mark on the gas tank cap.

Can't wait for the snow to try it out.

you might want to check and see that the vent line is not cracked.if it is the fuel might have been leaking from there.otherwise the vent line heads upwards to the steering hoop and should be higher than your filler cap,or maybe the vent line has pulled off the tank fitting.

Originally posted by swish@Sep 22 2004, 07:42 AM
you might want to check and see that the vent line is not cracked.if it is the fuel might have been leaking from there.otherwise the vent line heads upwards to the steering hoop and should be higher than your filler cap,or maybe the vent line has pulled off the tank fitting.
346906



Thanks...I'll check it out

I've had that happen on my 97 670 when overfilled. It will leak out the overflow somewhere near your left foot...looks like its just pouring out of there

That's right, all over my boot. Just don't overfill.