fuel valve leaking

I have been noticeing a trail running down the engine of my bike here lately. I originally thought it was my carb shaft oring but now am suspecting my fuel valve. Everytime I get on it in the mornings now, I notice a gas oodor. I have read many a post out here of rebuilding the fuel valve with no success or an unwanted result. I would like to keep it as original as possible so I don't want to change to an aftermarket mod. Any ideas?

 

You sure it isn't a fuel piping o-ring that let loose? That looks a little further inboard to be the fuel petcock.

 

Those carb fuel rail o-rings are hard to get at, it means you have to remove the carbs and break the rack apart. For ease of diagnosis, I'd check the rubber fuel line first, make sure there's no splits or loose clamps, etc.

When people talk about a petcock "leaking", they're usually talking about an internal leak, so that it leaks fuel into the carbs (which also means the float needles are bad, btw). The petcock could be externally leaking where it mounts to the gas tank, there is an o-ring up there that can go bad. But also make sure that the petcock is cinched tightly to the bottom of the tank via the two screws, sometimes they back out a bit. Also, there are two hard fiber washers under those petcock-to-tank mounting screws that serve as "gaskets" and they could be toast.

FInally, 700N carbs have fuel bowl overflow drain hoses on them, and one of those hoses could be "draining" fuel onto your engine.....again, it would point to a leaky float needle. Try repositioning the placement of the overflow tubes and see if the location of the leak moves, also.

I have all of the products you'll need to fix your leak, whatever the cause, in my parts-for-sale ad.....up to and including new replacement petcocks and fuel valves, or the rebuild parts for an original petcock (or I'll even rebuild your petcock properly, if you wish).

 

I am pretty sure it is coming from the bottom of the petcock valve. I have recently replaced the fuel line installing a new filter. The only other thing I can assume is it might be my vacuum port on the petcock or like Chacal said, the mount. If you notice the discoloration on the bottom of the petcock, This is where it starts that I can tell. You can see the trail it leaves. The bike is always on the kickstand.

 

There's an o-ring around the cock lever. From the looks of your picture, I'd say it's leaking.

 

That doesn't look like a fresh, overnight leak to me. If it is; you're leaking petcock is the least of your worries.

That leaking fuel's got more rust in it than gas.

That bike runs like that???

 

Sorry, that leak has been about 3-4 weeks since I have cleaned it. I wash the bike about once a month.I will clean it after work and post when it shows again. Tank is clean. think I have something rubber disintagrating or it is just road grime. daily driven rain or shine about 35 mile a day. This IS NOT an over night thing, has been getting worse over about the last 3 months.