Fuel Leak….

[AussieHard]

Came home late last night, and haven't been out today...Walked past the garage and could smell petrol. First thought was damn forgot to turn the petcocks off...

Nope both off but there is a puddle of fuel under the bike. Can't see where is is coming from.

I have no centre stand so the bike is always on the side stand. Due to gravity the puddle is obviously on the same side as the stand.


First question, how much fuel sits in the carbs, is it enough to create a puddle. Could it have come from there.

If the petcocks are working, and shutting off where else can it come from?

Is the most likely cause faulty petcock seals?

It is a 74 so had early type petcocks not the later gravity ones.

Hoping to get some direction so I can take a proper look in the moring with some day light.

Cheers.

 

[DogBunny]

You probably have both a leaking petcock and a leaking float bowl needle valve.

 

[AussieHard]

Was doing a bit of reading seems to be a common problem.

 

[AussieHard]

Is Mikes the only place to get petcock refirb kits?

 

[pumps]

I think if you look around there are lots of places, heck even ebay. Have you tried a local parts place or Yamaha dealer? I'll bet one of your mates here that rides an XS knows someplace closer than mikes..

 

[AussieHard]

Local Yam dealer just got bought out by the Harley dealer. No they don't have any parts for the XS, I tried many times.

If any of the Aussies know.

 

[Phyberoptic]

Local Yam dealer just got bought out by the Harley dealer. No they don't have any parts for the XS, I tried many times.

If any of the Aussies know.

Just take the petcock in.... many of them are the same internals and gaskets..... have the parts guy pull a couple out and see if it fits.

-=PO

 

[XSLeo]

Pull the fuel lines of the petcocks, put on a long line, so it reaches into a jar with a scrw on lid. Punch a hole just big enough for the fuel line. With the lid on, line in jar, The hline in a snug fitting hole in the lid stops the fuel from evaporating.
Let it set over night, any fuel in the jar means the petcocks.
As dogbunny said probaly both the petcocks and float valves.
You can try taking the cotton off a q-tip and wrapping it with 4 0 steel wool to clean and polish the float valve seats. closly inspect the float vlave needles. Even a very small groove around the tip will leak.
Replace whats bad.
Leo

 

[AussieHard]

Thanks Guys I am thinking it may be both. There seems to be damp residue around the back of the petcock, and today when I kick started the bike the carby seemed to dump fuel.

Will have to place an order with mikes & wait a few weeks for it to get over here.

If the other gaskets/seals are in the same condition at the gas cap was.

 

[pumps]

Looks familiar. I had ordered a new cap seal and when it came I took the old one apart. I thought there was a piece missing in my kit until I realized the old one was in such bad shape that it was just in two pieces instead of one. Looks like the same in your second left picture.

 

[xjwmx]

That's all pretty messed up, but for just a leaking petcock you could install lawn mower inline valves.