Small Engine Question

[Racinfan83]

Try to make this as short as possible.. I have an old Craftsman 3-20 snow blower that someone put out for the trash a few years ago. I picked it up, took it home, cleaned and fixed a few things, and got it going. Works like a champ. BUT - it has always leaked gas from the carb somewhere. Rebuilt the carb, all new o-rings and gaskets, new throttle shaft, new fuel line, etc. If I don't run it clear out of gas every time it will leak everything out til the tank is empty. Getting tired of cleaning 2 stroke gas off my garage floor. I'm out of ideas. Probably something stupid I have completely missed? Ideas?

[John Boothby]

I don't know much about those small engines, but is there a float assembly? If so, maybe the float is stuck or for some reason not seating properly?

[Franke]

Is the fuel tank located above the carb with a fuel line to the carb? Check for hairline fracture in tank , line or carb. Use a dye in fuel to identify the leaking area after good cleaning. Possibly if you have a fuel line from tank to carb, you can insert a small fuel line valve to shutoff fuel at the tank.

[Racinfan83]

Fuel tank is actually level across from the carb. Brand new fuel line. Seems like it "siphons" all the gas out of the tank. Should it be vented or not vented to prevent this? (Not much of an expert on siphoning) Thought of the shut off valve idea and may have to do that - but I would have to cut a hole in the housing in order to be able to operate it...

This is it:
http://i72.photobucket.com/albums/i178/Racinfan83/Erics%20Other%20Stuff/DSCN0151.jpg

[Dynomite]

I don't know much about those small engines, but is there a float assembly? If so, maybe the float is stuck or for some reason not seating properly?

I would go with float........but I assume a carburetor kit would solve that with a new float valve and seat.
And if it does not idle or otherwise run smoothly........clean out the idle jets with a small needle as they are the first to get clogged up when the gas evaporates out of the carburetor bowl.

Would also go with high floatation tires or wider tires so it is easier to push ;)

Amazing what some throw away.......one man's trash is another man's treasure :D

[Racinfan83]

Yeah I changed the float, and needle/seat when I rebuilt it. Jets are clean and it runs good. Don't think that's it... And it beats the heck out of shoveling... Just wish I could leave gas in it without a mess...

[John Boothby]

Did you adjust the float properly? Just asking.

[Racinfan83]

Not sure how I would adjust it? The float is round, and a pin goes thru 2 tabs on the back of it. The needle has a tiny bent wire on it that goes over a tab on the bottom of the float where it attaches. I guess u could bend that but I wouldn't know which way or how much?

[scottfab]

I'd approach it differently. I went for isolating the issue.
I did this on my generator. Same issue. Fuel disappearing.

Get some dry wall compound. The dry stuff. (or use flour).
Take some compressed air and with the powder in your hand blow
it all over the carb area. I did this outside then brought it in and
let it sit. This should crate a nice film of white all over it.
It took three days but I finally nailed it.
There was a small drain screw at the bottom of the carb float bowl on mine.
It had a VERY slow leak such that nothing dripped. It just evaporated
as it came out!
GOOD LUCK !~:cheers:

[Racinfan83]

This one is the opposite of yours. Mine "disappears" all over the place :p

I read some stuff online (manuals and such) yesterday - gonna try to set the float level properly when I get a chance and then pick up a shut off valve....

[Dynomite]

Did you adjust the float properly? Just asking.
Concur ........

Not sure how I would adjust it? The float is round, and a pin goes thru 2 tabs on the back of it. The needle has a tiny bent wire on it that goes over a tab on the bottom of the float where it attaches. I guess u could bend that but I wouldn't know which way or how much?
Usually you just bend a tab such that the float can close the fuel valve when the fuel gets to a level just below the overflow or vent. It is kind of trial and error (but on most carb kits you get a gauge to use for float setting). But if there is no gas coming out the vent then the float level should be OK. If the fuel is overflowing the vent you can see it drip out the vent tube which may be a plastic tube connected to the bottom of the carburetor bowel of any length (find the end of that vent hose).

On my Yamaha Raptor 660 Carb Float in the left photo there is a silver tab you bend such that the floats allow the fuel level to approach the top of the Vent.

The Vent is the long tube in the second photo that is vented to air out the bottom of the carburetor bowel. This by the way is what allows the fuel to evaporate and the carb bowel to go dry if left sitting for a few months. If the fuel bowel goes dry too many times the bowel becomes coated with a coating that does clog up the idler jet.

The Yamaha Raptor 660 has dual carbs unlike my Raptor 700 which is fuel injected and no issues with the Raptor 700 sitting for several months except I DO DISCONNECT the battery on both the Raptor 660 and Raptor 700. Both the Raptor 660 and Raptor 700 are modified considerably :p

http://i287.photobucket.com/albums/ll142/dynomite007/Dynomite4/c394b471-d295-45a6-90cf-9baf8c1cebf1.jpghttp://i287.photobucket.com/albums/ll142/dynomite007/Dynomite4/f8bfde1b-9bcf-4b17-9a70-b369d75c510c.jpg
http://i287.photobucket.com/albums/ll142/dynomite007/Raptor%20700/1b6b3202-722a-4d46-94f2-5ca75d7f5591.jpg
http://i287.photobucket.com/albums/ll142/dynomite007/A%20Raptor/86dc1b01-7ddc-4a7e-9140-facad131252b.jpg
http://i287.photobucket.com/albums/ll142/dynomite007/Ridgecrest0719.jpg

[Racinfan83]

Yeah that's a definite possibility. I read in a service manual I found online that you lay an 11/64 drill bit across the Carb flange and bend the tab til the float just touches it. I know that sounds a little "kludgeish" but that was straight outta the Tecumseh service manual. I did not know about a vent - but there is a tube on there I didn't know what it was for. So that's probably it. Will check/adjust this this weekend and see what happens.. Thanks!

And BTW - those Raptors are baaad! I rode one a few years ago and couldn't believe how much faster it was then my old modified Warrior (it WAS fast til my son blew it up)...