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removing fuel tank

Discussion in 'Bling and Appearance' at netrider.net.au started by geeth, May 6, 2009.

  1. I am thinking of taking off my fuel tank to check out the lines etc.
    The issue that I have is that my petcock doesn't have an off. It's On, Pri, Res.

    From what I have read up I should have the petcock set to 'on' and there should be a vaccuum seal to stop it pissing out fuel.

    Can anyone confirm this or give advice.

  2. Yes.
    Unless the automatic shutoff is f***ed, in which case be prepared to catch
    the fuel in a bucket.
  3. After a while they never seal properly anyway. so be prapared for a few drops.

    don't do it with the tank full and store the tank on a bit of an angle.
  4. I take it by on an angle you mean front down.

    I am expecting to tank to be pretty much empty by sat, if not well looks like I will have to empty it. :LOL:
  5. No. Get the tap high, without getting the filler low.

    If your tap is good, you won't have to worry. Just saying, be prepared.
  6. So I got the tank removed and one of the fuel lines had a small split in it.
    As the hose was very small and tight I am thinking of getting a replacement but having the length about an inch longer. Will this cause issues?

    I noticed that the fuel lid doesn't completely seal (put tank on an angle) and that the pet cock does dribble a tiny amount.
    I don't know if these would be issues or just as it's meant to be.
    Any ideas?

    Also just as a rough estimate, what do you think the cost of a 20 cm fuel line be?

    Also the clamps that held the broken line on where the tiny little thin metle things - i think it's called a scissor clamp - would it be best to replace with this type?


    At least gave be a better angle to clean a tricky spot that as been annoying me.


    This is the type of clip - sorta - that the bike had on it to start, expect crappier

  7. Cap? pretty normal. They have to have a small vent for the vapours.
    fuel tap / petc0ck = not ideal but it may just have a bit of grit in it.
    A tiny seepage is normal, but not dripping.


    Yes I always use screw-type clamps where possible,
    else heavy-duty spring clamps (like this) if I just can't fit a proper
    screw-type clamp in.

    The cheap wire clamps are almost worthless, they
    barely do the job on a new bike and are supposed to be replaced every
    time because they lose "springiness"/tension.
  8. Thanks for that. I didn't think that the cap was an issue, but figure while I have a reason to ask why not.

    I didnt like the spring clamps, I think went I have time I might give the bike a look over and replace.

    Good to know the fuel lines don't cost much, didn't think they would.

    What about a slight increase in length of the fuel line (it's the reserve one) I think that with another inch it will just make it easier to work with.
  9. Just don't make it too long that it kinks.
  10. So you want to add an inch to the length and you have a leaky cock? Have you had your Doctor check your prostate?

    Are you making sure you use your cock enough to stop it seizing?
  11. I don't know about other bikes, but on mine underneath the tank where the fuel line connects there is a flathead screw you turn 180 degrees to turn the fuel off.
  12. Well, got the tank off and on right.
    The new screw tight clamps where a little fiddley but got them on and lost skin but meh.

    Unfortuantly where the hoses connect under the tank I unable to tighten the clamps so I will be getting a few squeezy ones.
  13. There's no reserve fuel line. Normally there's just one fuel line (the bigger one of the two). It carries all the fuel whether you are on ON, RES or PRI.

    Inside the tank the fuel tap has two openings (usually short vertical tubes to save picking up the dregs from the bottom of the tank). The ON pick up tube protrudes further into the tank and therefore stops picking up fuel when the fuel level is still quite high. The reserve tube is shorter so can drain fuel from a lower level. All you're doing when you switch from ON to RES is selecting which pick-up the fuel is allowed to drain through.

    The PRI position allows fuel to drain through the tap by gravity, bypassing the vacuum tap altogether.

    The second, smaller tube on the fuel tap is the vacuum line and doesn't carry fuel. It attaches to the carb and when the engine is running the suction from the engine through the carbie is enough to lift the rubber diaphragm in the fuel tap by sucking on this line. This allows fuel to flow. When the engine is off a small spring inside the tap closes the diaphragm and stops fuel flowing. A leak in the vacuum line stops fuel flowing as there's not enough suction to lift the diaphragm. So good that you changed it. Extra length won't hurt as long as you don't kink the tube. It has to have a tight seal to work. Similarly anything that stops the spring sealing the diaphragm (i.e. dirt) will cause fuel to keep flowing. The tap usually has a fine mesh filter over the pick ups inside the tank and it needs cleaning every now and then. It's part of the fuel tap assembly so you have to unbolt the tap to get to it.
  14. Thanks for that.