Carby Gas keeps leaking from the Bike, can't figure the fix..

Discussion in '2-Stroke Engines' started by Zalaki, Jun 28, 2011.

  1. Zalaki

    Zalaki New Member

    Well gas is leaking from the bike and dripping down onto the floor, like a good amount already. I have changed the fuel lines from the old ones to 1/4inch hoses and then went to 3/16 or something. I couldn't find clamps for the 3/16 so re-installed the 1/4 but the clamps don't fit the hose I have.

    I also was reading that it could be the shut off valve to the gas tank, while searching the forums but im not sure how I would be able to inspect that or find out if thats what is the cause. This is the only reason keeping me from riding my decked out bike around and it's eating me away inside not being able to fix it.. :(

  2. Stan4d

    Stan4d New Member

    Last edited: Jun 28, 2011
  3. Zalaki

    Zalaki New Member

    Thanks. Had no clue what to search for... tho im new to this I hope at least one of those threads is newbie freindly :/
  4. Big Red

    Big Red Active Member

    Gas leak.

    Hey Zalaki, Welcome.
    Again, As always, so far, (just kidding Stan) Stan4d is most likely right. The top tabs on the float mechinism tend to hit the top of the carb. Not letting the needle seal the gas inlet. a slight bend will do the trick.
    Big Red.
  5. Stan4d

    Stan4d New Member

    Making me laugh V.
  6. motorpsycho

    motorpsycho Active Member

    to check the shutoff valve for leaks, simply remove the fuel line and leave the shut off in the off position.
    let it sit for awhile and then check to see if there's a puddle under the bike.
    Maybe put a papertowel on the floor for the gas to drip onto so you can see if the shut off is actually leaking.
    A lot of times the shut off valve will still allow gas to slowly come out even when it's turned off, and if the float level is not set right, gas will overflow out of the carb vent tube.
  7. Big Red

    Big Red Active Member

    Gas Leak.

    Hey motorpsycho,
    You're right about checking the petcock, but if the float valve is set up right you don't REALLY need to turn it off. If I had to remember to turn off my valve everytime I rolled in at 3 in the morning, well, I'd just lose a lot of gas.
    Ajusted properly the needle and seat work quite well. If I don't plan on riding for a few day's I'll check to make sure it's off, but otherwise I close it when I remember to, sometimes, once in a while, maybe, well, you get the picture.
    Big Red.
  8. HeadSmess

    HeadSmess Well-Known Member

    hows about the tank bolts themselves?

    mine had each and every one slowly develop cracks, hence leaks :)

    cure so far has been to hit em with, in this order, a bit of hydrochloric acid applied from a zinc rod (flux!), a big 200watt soldering iron (she gloooooows!), and some solder :)

    when i get a new tank the first fix is too solder some washers on with the torch before i fill it with petrol :)

    ive never really had a leak anywhere carby leak that flooded me crank and thats it...
  9. wbuttry

    wbuttry Member

    also it will seep from around the threads on the petcock screws into the tank bottom i put a piece of black tape on my hose nipple where it screws down in the tank and i got mine to quit leaking
  10. Big Red

    Big Red Active Member

    Petcock Threads

    Ya use teflon (pipe thread) tape for that. also, elec. tape WILL MELT in gas.
    Big Red.
    Last edited: Jun 30, 2011
  11. Big Red

    Big Red Active Member

    Tank Bolts.

    Yeah Bro, I've got 3 or 4 tanks standing in line to be fixed.
  12. wbuttry

    wbuttry Member

    hasnt yet and that was in december
  13. V 35

    V 35 Member

    My Skyhawk had a gas leak too, what freaked me were the black chips in the fuel filter,
    came to realize, they are paint chips, the tank seams are bad ! I drained the tank, and scuff sanded the seam, than applied a thin coat of JB weld to the seams, Should cure it !

    The stock petcock never worked right, Pirate Cycle has a nice replacement.
  14. motorpsycho

    motorpsycho Active Member

    oh man, more j,b, weld!
    j.b. weld is an EPOXY that will deteriorate when it comes into contact with gasoline over time.
    the only correct way to fix a leaking gas tank is either brazing it, or silver soldering it.
    I really hate j.b. weld, and how a lot of people think that it's a "fix-all" cure for everything that is broken or leaking.
  15. Big Red

    Big Red Active Member

    Paint chips

    Thanks Motorpsycho, Yer right again.
    The paint chips are a problem but all ya gotta do is scrape or sand it off. If you're talking about a 2 cycle then ya got oil in yer gas, right? Then ya never have to worry about it rusting couse the little gas that splashes on it will keep it in good condition.
    Big Red.
    P.S. I don't even own a tube of J.B. failed.
  16. HeadSmess

    HeadSmess Well-Known Member

    and regular soldering works just as well with a big enough iron to get the heat. and zinc chloride flux... no flames needed.

    i just got a new tig welder...aluminum capable :) such a long list of bits to make but fuel tanks up there at number one or two!
  17. joeltrain

    joeltrain New Member

    I store my bike inside my house and the sucker was stinkin' me out. I couldn't figure it out. Until one day I happened to be looking at the carb and noticed a drip from the drain screw. The red washer supplied with my kit was the culprit. 13 cents later my problem was solved. I thought I had the problem solved whn i found the washer for the drain on the tank. I had installed it with teflon tape, and it didn't work. For some reason the tank drain doesn't leak even tho the washer's made of the same material as the carb drain.

    My 1st install had a stuck float that seems to be a very common problem with the Speed carbs. The CNS has a much better float design but unf those things are :poop:I never was able to get it to run right with that, so i put my speed from my 1st motor on. Just a note, if the drain on the tank is leaking your fuel line will be wet with gas. If the line is dry you're prob is either the float or the bowl drain. Good luck and don't smoke!