Snowmobile Leaking Gas

[Fisherman 1]

The needle is in backwards.at least most engines the needle pointgoes up in the carb.

Good eye, that's what I would say too, the rubber tip end should be the other way around in the hex head cover. 

[eriksat1]

Good eye, that's what I would say too, the rubber tip end should be the other way around in the hex head cover.

Yup the needle is in upside down in that picture the tapered tip of the needle sits down inside the seat not up on the float.

[jethro]

Do you guys use 3/16 or 1/4 for fuel lines?

Check the ID of the carb inlet and do not go smaller. Get Tygon lines.

[Huntindave]

So I took the leaking carb off. in the pictures below you'll see me pointing to an overflow fuel line that has a cap on the end. I noticed that cap was very lose and actually dripping gas.

Anyways thanks for your help everyone! really hoping it's as easy as just fixing that leaking cap at the bottom of the carb bowl.

The overflow tube and cap is fine, nothing to fix, it is working as intended. Yes the carb is over flowing because the needle is not shutting off the fuel flow when it is supposed to.

Where does the excess fuel go?  It goes out the overflow tube as it is supposed to.  Why does it leak past the "cap" on the end of the overflow tube? Because it is supposed to.  The "cap" is designed to pass fuel but stop debris and contaminants from entering the carb.

[Kevin23]

Sure does look like that needle is upside down

[smokey66]

Needle upside down and possibly missing a spring retainer. You might want to take the other carb off to compare. Then you'll know how it's supposed to look.

[JonPerry]

If you've lost the small wire clip that attaches to the needle, you may as well pick up a couple carb kits, rebuild them & begone with it. The clip holds the needle to the assembly that moves with the floats.

[DR.SPECKLER]

Right the needle jet will fall right out with no retaining clip.

[bassin212]

I have another Cat, and I don't believe that one has a needle retaining clip either. a lot of videos I've seen have them for dirtbikes and motorcycles, but not for older snowmobiles.

[eriksat1]

The little clip is what opens (lifts up) the needle when the gas in the float bowl is low, then when the float bowl is full the metal tab on the float pushes the needle closed down in the seat.. It is called a needle and seat not a needle jet. There is a high speed jet but that is not your problem..

[bassin212]

I stopped by a snowmobile parts store. Turns out there is one close to where I work. He said the needle is definitely upside down because the float is sitting way too high, causing the gas to leak through. I'm just going to flip it around and if that doesn't work, I went ahead and bought some fuel line and a cute off switch. He said not all snowmobiles have the Clip or seat on the needle.

[DR.SPECKLER]

The floats are sitting too far down with needle in backwards.letting fuel flow and not shut off.if the floats were too high fuel wouldnt flow because the needle would be in the carb seat sealing fuel off.fwiw i work on carbs daily.anyways you will be up and running in no time.

[eriksat1]

When holding the carb upside down compared to normal running position the float should be pushing the needle closed and the float should be almost perfectly level not tilted up or tilted down. perfectly level. Your whole problem might just be someone put the needle in backwards. If the float is not level you bend the little tab that pushes on the needle up or down a little until the float is sitting level when fully closed.

[DR.SPECKLER]

There are float level specs but i think its just the needle got installed upside down too.make sure the needle tip isnt damaged.if the needle is mucked up it wont stop gas flow from not being seated fully also.

[eriksat1]

Don't plug off the vent tube if it still leaks. Take the carb to someone who knows what they are doing. Needle and seats do get worn out and leak. That is why they come in a rebuild kit. If you need to just order a new needle and seat try Dennis Kirk.com

[DR.SPECKLER]

Yup.plugging off that overflow will make all that gas thats going out the hose  fill the engines crankcase up full of gas if plugged.

[bassin212]

everything looked really clean, and the person I bought it from did clean the carbs. So i'm thinking they just but it in upside down. Thanks for the replies everyone. i'll let you know how I make out!

[Kevin23]

everything looked really clean, and the person I bought it from did clean the carbs. So i'm thinking they just but it in upside down. Thanks for the replies everyone. i'll let you know how I make out!

That's what I was going to say, they probably cleaned the carbs right before they listed it for sale and just put it in upside down.

[bassin212]

looks like the flip did the trick. thanks everyone