OK, well I had'ta figger it out fer muh'self....
I want to set my sled up with an aux gas tank like I have been running for the last 25 yrs. It's more work and investment up front, but a lot more better when it's time to ride.
I figger on making an alum tank that will set just behind and a bit above the OEM tank, and then I plumb them right into the vent line on the main tank, and let it suck it dry.
The very nice points of this are that you can fill it clear up if you want for a big ride, or even an overnight ride. (planned or not eh?) If you don't want any, don't put gas in it. I think my old tank on my ZX weighs 12# @ 10 gallon capacity. But the aux tank empty's first as it continuously refills the main tank as you ride, where that five'r on the back is still there....
Of course the part about not having to try to pour gas in the weather, or possibly getting snow in your tank, or ....
I just find it so much better to toss 3-4 gal in the back and suck it dry right away, and not frett over gas - even on the [planned] short rides.
Years ago me and my chum sucked down 20 gallons breaking trail (and subsequently camped out overnight) on our old 600 / 136's. (1990's) I will say tho that I don't think that we have ever used more than 15 gallons since we got out 800/151's or longer. But I have hopes of some big rides in the future yet, so ....
EH _ KNEE _ HOW .....
So I pulled the plastic back and found the vent line. Just setting in the garage - the tank was still under pressure when I took the cap loose. (good grief...)
So here you can see where the fitting fit into the tank neck, just below the cap:
You jist need to back out the T15 screw (that you can't git to) and the fitting pulls out. It has an O-ring seal on the outside:
Inside you find just a piece of rubber that is acting as a check valve. I'm sure that if you wanted to "fix the problem" all you'd haf'ta doo is grab ahold of it with a needle nose or whatnot and pull on it to break it, and then put the fitting back on. I'm not sure if I'll just "fix" this fitting, or make a new one for my porpoise?
I have heard of a cpl of tanks imploding before as well, and I would venture to guess that the other end of the vent line - which comes out above the left shock got iced up / plugged, and the fuel pump had more suck than the plastic tank had structural integrity. Traditionally these vent lines use'ta go down to one foot well, double back up over the top and back down and vent out above the other foot well. It may not be 100% drip proof, but by going all that way - I don't know that I've ever seen one drain out - no matter how long a sled was upside down, so ....
I would not recommend just clipping the rubber seal / check valve and letting the vent line go strait out to the ski recess in the pan like OEM. I am sure that you would end up with a lot of drainage, so if you go this route, I would highly recommend that you go with the old skewl looped vent line like I just mentioned above. It worked fine for decades prior...
FWIW - mine is an '18.
Also outlined a bit in post 50 above.
Most I see have it. Gets worse and worse over time. Are they designed like that with the curve at the end or doo you think it's a defect?
www.snowest.com
BTW - The vent fitting takes 1/4" ID line in case anyone wants to make the change.
I'd be willin' to bet that the porpoise that they went with this design is for EPA mandates regarding gas tank evap.
Same as that "Service Engine Soon" light that comes on if you don't git'cher gas cap on your truck tight enough.
Sure glad someone is lookin' out for my well being!
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