81 gs 650L leaking gas

[Anonymous]

I've been reading these forums for a while now. Just have hopefully a simple question.

Gas has been dripping out of carb # 2. Through the breather tube.
I've rebuilt the petcock, and It seemed to be a bit better for a week or so. I thought it was the spring in the petcock.

Now for my question. Could it be the petcock if it's dripping while the bike is running? The more I thought about it, It just doesn't make sense. If the petcock is in the on position. It's allowing gas to flow. It's not doing anything but allowing it to flow. So if it's leaking, while running it couldn't be the petcock.


any thoughts would be appreciated.

[Anonymous]

It could be a bad vacuum diaphragm in the petcock, as that's what's hooked up to #2. But another possibility is a stuck float. Rap on the bowl of #2 with a screwdriver to see if it unsticks.

[whodatpat]

Leaks only while it is running? Then the problem is likely the nedle valves in the carbs. I had same problem. Off the petcock would stop the flow of gas to the cards so they were ok, no leak. When I ran the bike, petcock on or in your case vaccume opened, and especially at idle, the bowls would overflow, and #2 is the first one to leak because that is the first one in line from the gas tank.
The good news is that the carb cleanup section on this site has all the answres. And a novice do it ourselfer can handle it. The bad news is you will have to take the carbs off for a few days.
Patirick
80 GS850 G

[Anonymous]

It is only leaking while running

Thanks for the replies. I really want to hit it with a hammer!

[whodatpat]

That might work too. It could shake the dirt loose in the carb and cause the nedle valve to close. From the looks of my carbs, someone "fixed" them that way often.
Patrick