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Phil_Norwich
HELP!!

Last night at work my manager said is that your bike that stinks. Walked out and I could smell petrol, walked over to the bike and the fuel tap was on. So I turned it off and the smell went away, I couldn't see any petrol on the floor mind.

Today I decided to have a look, turned the tap on went inside, came out and I had a nice little puddle on the floor. It looks like its coming from the carb, I can see this little pipe dripping it, but not sure what it is. I'll get pictures later.

When I brought the bike he said if you leave the tap on you get the smell of petrol but no leak. He was right butt now i'm getting a leak.

It explains why I had to switch to reserve about 15-20km earlier than I normally do.

Any ideas of what it could be and how to sort it?

Thanks Phil.
Billy M
sounds like your needing a new tap
Anth
Could the float be stuck open, so the carb get's flooded and overflows (I don't know if carbs have breather pipes at all- I've never looked for one).

If you can, I'd whip the carb off and clean the insides- othewise it might be worth looking into a new tap as Billy suggests.
Wilf
I had a bike with a dodgy fuel tap and if any grit got in the carbs they'd overflow. I fixed it by buying an inline fuel filter and fitting that. It prevented grit getting into the carbs. You only have to snip the fuel pipe and the filter is just a push fit.
Phil_Norwich
Thanks for the replys guys.

Its leaking from the little nossle that can be seen in the picture.

Me and my mate were looking at it today, we looked in the DR350 (my engine is based on this one) and its leaking from the drain plug. Considering I haven't got a bloody clue what I'm doing we undid the drain screw and drained the carb. Its still doing it, this morning it was a few drops but now its a steady stream of expensive petrol.

Parts are a bastard to find for this bike, would a fuel tap from another bike fit?

Anywho I'm going to get on the phone to my breakdown tomorrow and see if they can get my to a garage. If not i'll be pushing it a mile then phoning them.

I'm not too confident about taking my carb apart, I know its all a learning curve. But the Goose needs a good service anyway including, tappets, rear wheel bearings and a general service. I sold my CBR125 today so I have some money to spend. I'll be getting it serviced this week. I want to get a professional service done then i'll service it myself from here on out.

BikerGran
If the leak from the carb stops when you turn the fuel tap off then
a) surely that shows there's nothing wrong with the fuel tap
and
b) the problem can be solved by turning off the fuel tap when you're not riding it. (that's what it's there for)

The leak won't happen when it's running cos the fuel will be drawn into the engine.
fastfitter
What BG said - always turn your tap to 'Off' (if it's got an Off position) when you stop for more than a couple of minutes.

As you can see in the picture ....

IPB Image

fuel flows into the float bowl from the tap. There's a pointed valve in the bowl so that when it's full the float errr floats on the petrol and pushes the valve shut, closing off the petrol supply.

If you get a speck of muck on the tapered seat of the pointed valve it won't shut properly. If you're lucky the petrol leaks out of the float bowl overflow. If you're unlucky it can leak into the engine. Apart from diluting the oil it can fill the combustion chamber or crankcase and cause a hydraulic lock. This can cause severe damage when you try and start the bike - I have seen pictures of con-rods bent by this.

If you are getting a dribble from the overflow you can sometimes cure it by giving the side of the float bowl a tap with the handle end of a screwdriver - this shakes the float and the needle valve and can dislodge any muck, allowing the valve to close properly.

Of course, the correct fix is to pop the float bowl off and clean it out, making sure the needle valve and it's seat are also clean.
Phil_Norwich
I always try and make sure that the fuel tap is turned off, but sometimes you forget. Got it to a garage today and he said its probably the needle valve. We'll wait and see.

mrteapot
It looks like the needle valve is sticking allowing fuel to overfill the carb bowl and leak out of the overflow vent. (That pipe could be the float chamber drain- also check that the drain screw is tight- pic is not very clear!))
Phil_Norwich
yeah pic is pretty crap.

Well anyway its at the garage and hes sorted it. Just getting it serviced and looking into the compression issue.

He ran a compression test and it came u at about 100 when its supposed to be 160 (don't know exact figures my dad just went too see him).
Billy M
QUOTE(Phil_Norwich @ Apr 30 2008, 04:44 PM) *

He ran a compression test and it came u at about 100 when its supposed to be 160 (don't know exact figures my dad just went too see him).



Oh thats not good mate, 100psi from a bike engine is very low. sounds like there might be an engine rebuild for your bike mate
Phil_Norwich
yeah fun fun fun. He said he'll look into it more tomorrow.

Luckily I just sold my CBR, if not there would have been problems.
newbarker
QUOTE(Billy M @ Apr 30 2008, 04:50 PM) *

Oh thats not good mate, 100psi from a bike engine is very low. sounds like there might be an engine rebuild for your bike mate

Dan would agree that 100PSI is the minimum.
Wilf
That's a very good link Newbarker.
I'll test my compression when it stops raining.
Defiler
*Very* good link. That'll save me a lot of faffing whilst checking the compression on the Duc. I don't expect it to be out-of-whack at all, but it's part of the service. On the other hand, I'd have had a problem with not even considering opening the throttle... blush21.gif
Billy M
QUOTE(newbarker @ Apr 30 2008, 09:47 PM) *

Dan would agree that 100PSI is the minimum.



well am i glad the DAN agree's rolleyes.gif compression testing is a simple job that can pinpoint the start of problems, so its probably one of the best diagnostic( is that the right word?) checks you can do!
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