leaky fuel line/tube

Discussion in 'General Questions' started by ty151, Jul 12, 2009.

  1. ty151

    ty151 Member

    Just finished up my RAW 80cc build a few days ago and noticed that my fuel line is leaky at all the connections. I have an inline fuel filter and with that connected, it leaks a little bit at all 4 connections. It drips all over the ground when i stop riding and put the kickstand out. I have tried using zip-ties to tighten up the line but it hasnt worked, so does anyone have any ideas? Thanks

  2. Mountainman

    Mountainman Active Member

    strange -- kind of ??
    most of these fuel lines just slip over and seem to hold with no clamps
    sounds like you could use
    some very small hose clamps sold at the local auto parts store
    probably the smallest size in their clamp display rack
  3. ty151

    ty151 Member

    Yea I will have to give those hose clamps a shot.

    And sometimes it seems like when i turn the gas off, it doesnt ever really turn off. Anyone w\know whats going on there?
  4. lordoflightaz

    lordoflightaz Member


    Try taking the fuel line off with the petcock closed. More than likely you will see fuel slowly drip out. Move the lever so that it totally stops, Use a "Sharpie" or scribe a line into the valve body to mark the place that is the real "off" position. Now when you shut off the supply line the lever up with the mark. This should help a bunch,

    It still may leak out between the connection between the tank and the petcock valve which you will have to seal.

    Around here we have been trying to leave a loop in the fuel line so that when the fuel is "off" it has to go up before it can run through the filter and carb to the ground. This seems to be working. When the petcock is open, pressure and gravity get the fuel around the loop without any issues.
  5. ty151

    ty151 Member

    Yea i have figured out where my "real off" position is but i just cant figure out how to keep it from leaking at the connections. It leaks the most at the carb. inlet so I used a hose-clamp and we will see if that works or not.
  6. HoughMade

    HoughMade Guest

    Zip ties? Hose clamps are called that for a reason. There are even spring clamps down at the hardware if you don't want worm drive clamps.

    Take a gander under the hood of a car or on a motorcycle some time. How many fuel lines are held on by hope or zip ties there? If holding your gasoline in less important? Doing this right is worth the extra $2.95 for a few hose clamps.

    Zip ties on fuel hose is a pet peeve of mine...I can't decide if it bothers me more than JB Weld on...anything....nope- nothing annoys me more than JB Weld.

    You will not regret taking the time and spending a few shekels to do a quality job.
  7. ty151

    ty151 Member

    I already have hose-clamps on there and it doesnt seem to be working, its almost like its worse than it was before
  8. HoughMade

    HoughMade Guest

    Then you have the wrong size fuel line. What I mean is, the line that came with the kit may not be the best. Try some automotive grade fuel line. I spent around 3 bucks for 2 feet- plenty left over.
  9. ty151

    ty151 Member

    Yea thats what Im going to try now. Any particular size i need.
  10. just buy a few diffrent sizes and try each one until you find a very tight fitting one.
  11. Mountainman

    Mountainman Active Member

    take a MB ride over to the Auto Parts Store

    take your MB over to the Auto Parts Store
    these guys are more than happy to come outside and take a look

    they will hook you up -- if you let them....

    makes it best when riding that MB THING
  12. icyuod2

    icyuod2 Member

    i hit my local auto store for hose clamps. they wanted $12 for a pack of 10 and i only need 2.

    so i used a peice of copper wire and twisted it around the hose.

    hasn't leaked a drop since.
    there ya have it, real cheap hose clamps and ya probably won't have to leave the house to get. :)
  13. Pablo

    Pablo Motored Bikes Sponsor

    Make sure you get fuel resistant hose.

    1/4" for tank to filter

    3/16" (or 5/32" -7/32" or whatever next smaller size they carry) for filter to carb

    Actually with proper fitting fuel lines, good zip ties are perfectly acceptable and hold more round than small hose clamps - and they won't tear the hose up. I fail to see why they should be compared to something so cheezy as JB Weld....the zip ties (or wire) shouldn't be depended on for leak stopping, just added mechanical pressure.

    Lastly you should also get a good fuel valve. The supplied one will break eventually.
  14. Porkchop

    Porkchop Member

    Now the copper wire will end up cutting it's self into your fuel lines. And sometimes clamps actually cause rubber hoses to kink up and leak. But if you have the correct size line on your bike and get the propper sized clamps it should solve the problem.
  15. HoughMade

    HoughMade Guest

    You and I agree- JB Weld is far cheesier.

    For me...and maybe it's just me, I'm not saying zip ties won't work. Obviously they do. It's just that there is inexpensive hardware made specifically for the purpose. What works for you, works for you and given the advances you have made for MBers, I do not want to imply a lack of quality on your part. Clearly you know what you are doing. I just like using the hardware made for the purpose for that purpose.

    One slight advantage is that I can take off the hoses and replace them while reusing the hardware...but I suppose that's not a huge advantage. Zip ties are great. I use them, but not on my hoses. Others do. Perhaps I was too harsh, but as a lawyer, I suffer from the terminal belief that I have never, and will never be wrong about anything. ;)

    One last thing. You are right about the hose sizes. However now I just use 1/4" and I heat up the ends with a heat gun on low to get them over the larger barbs. they shrink back when they cool and can be taken on and off while fiting well thereafter....but be careful with that heat gun around gas.
    Last edited by a moderator: Jul 14, 2009
  16. Pablo

    Pablo Motored Bikes Sponsor

    No issues.

    One thing, IMHO, 1/4" is way too huge for the HT carbs I've messed with. There is no kind of clamp that would work properly with 1/4" hose on that small (non-tapered) single barb inlet. That's why I said to use a smaller hose after the fuel filter (which is 1/4") and does require heat/manuevering to get it on.
  17. HoughMade

    HoughMade Guest

    Whoops- I meant I only use 3/16ths- no need to heat the 1/4, obviously.

    There you go- my first and only mistake of the day.

    Attached Files:

  18. icyuod2

    icyuod2 Member

    unless your pulling on the fuel line all the time(and i do mean pulling for all your worth), or the fuel line is so old its falling apart, a simple copper twist tie won't cut into the line.
    just use a heavy guage.
  19. HoughMade

    HoughMade Guest

    This is my last post on this subject (famous last words). Go to a decent hardware store. Not Lowes, not Home Depot, not Menards- I shop these places, but not for the hardware bits and pieces. Try Ace, HWI, Service Star, True Value- even better, any hole in the wall that has every little thing you never knew they made. How do you know you have found the place? It smells like moth balls and it stocks Mason jars.

    For under $3, you can get 4 of any one of the first three pictured below. Sized right, all work well. I have used all 3. The clamps in the 4th picture are a bit harder to find and might cost $5-$6 for 4, but are the best. Not necessary, but very nice.

    BTW- we all need at least 4 right? 'Cause we are all running a decent fuel filter (screen filters only mean that your carb will get blocked by smaller stuff).

    Attached Files:

    Last edited by a moderator: Jul 14, 2009
  20. icyuod2

    icyuod2 Member

    i went to my fav. auto stores up here in canada and the only ones i found in the correct size was a pack of 10.

    i have better things to spend $12 on.
    even if the copper where to cut through the hose after a year, i could fix and replace my fuel line 24 times for $12 (fuel line-$1 a foot)