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Fuel Tap Petcock question...

Discussion in 'Technical and Troubleshooting Torque' at netrider.net.au started by kuro, Apr 30, 2005.

  1. Hiya,
    I serviced my bike for the first time today.
    when took of the fuel tank i turned the fuel tap to the OFF position.
    Disconnected the fuel hose and the vacuum hose.
    When the fuel hose came off, petrol came out.

    - Is that normal even though the fuel tap was in the OFF position?

    Next i put the fuel tank on the ground and opening where the fuel hose connects to was leaking fuel.

    So what i did was i put the fuel tank on the ground upside down, to hopefully stop it leaking fuel everywhere. But as i was watching it, the fuel kept spilling out but only slower - but it was still seeping out.

    - Is that normal?

    Lastly everything bolted back up ready to go, i left the fuel tap in the OFF position, the bike started up fine, i went for two quick rides, turned ignition on and off for a few times the bike still started up fine.

    - Now is that normal?

    Appreciate your help guys. Thanks
    sorry for long post.

  2. er.......
    No I dont think that is normal.

    Even the 1967 model bike I have been restoring has taps that completely shut of the fuel when in the off position.

    You would think a modern bike would be up to that standard.
  3. ok if thats not normal, what do you think is causing it?
    is it something to be concerned about?

  4. A tap that doesn't turn off would probably mean the tap is faulty.

    Try riding your bike with the tap off, the bike should stop once all the petrol in the carbies are emptied, if it doesn't replace your tap.
  5. yeah i went around the block twice, didnt baby it either, it was running all fine with the tap in OFF mode... i guess i will try to ride longer in regards to what vic said...
  6. let me guess... CBR250RR??

    there is a diaframe (Have I spelt that right??) which acts like a fuel pump... if that brakes it will couse petrol to leak but the bike will run and most people will not notice the change in preformance of the bike...
  7. nah spada vt250...
    but anyway with fuel tap in it's condition that it is, should i be concerned about it or not?
  8. Dont bother with a longer ride, sounds like the tap is snafu

    best advice is to get onto ebay and find a new one.

    I just got a new pair for my BSA for half the price I was quoted from a dealer (the BSA dosent have a reserve tap instead it has a tap on each side of the tank and one side of the tank is lower then the other)

    Any way I dont think it is worth trying to fix, and if there is a problem with a seal it might somehow get worse, I say replace the thing.

    Might also be a good idea to rub a little liquid gasket on the thread when you screw the new one in too.
  9. maybe not so wierd..........I took my tank of last week to check the plugs and as this was a first for me, I consulted the owners manual..... and the intructions were " turn fuel tap to the ON position" so I figure that's wierd but I followed the intructions and when I removed the tank and disconnected the house, no fuel ran out..........beats me.....kwaka magic...
  10. Kwakas , well( older ones I know about) don't have an off position they have On, Reserve and Prime, fuel should only come out of the tap if a small amount of vacum is applied to the valve in the tap, except for the prime position, which is what it says used to prime empty carb's and the tap should never be left in the prime position unless your draining the tank on purpose.
  11. so in my case, leaving the tap in the OFF position isnt going to harm the bike at all? so i guess i shouldnt worry about replacing the tap?
  12. ok so this sounds really dumb, but i have no idea about taking fuel tanks off. does the tap and hose come off with the tank? and i'm guessing that it would be better to run with the tap in the ON position kuro, since thats where its supposed to be when your riding. but check the owners manual and possibly get a new tap/hose/whatevers broken so you can actually turn the fuel off. i wouldn't like my fuel tap to be always on...
    Did you state that you disconnected a vacum line from the fuel tap, ans what bike and model are you talking about.

    Some vacum assitted fuel taps in the so called off position is actually a primer function, and fuel will run freely when lines are disconnected.

    Thew only thing that goes wrong with these units is the diaphragm will get a small hole, then you will have no choice but to run it in the off position. BTW kawasaki's aint the only ones to use vacum assited fuel taps.
  14. the bike is a vt250 spada.
    i disconnected the vacuum hose and fuel line as per 'workshop manual' that i have. its actually a scan of the original one - so i dont know how genuine it is...