Petcock Mismarked????

[gbobst]

Anyway...look at this pic...I have my petcock turned to on, yet it is really off(stop). Does anyone have/know if this is an original petcock on my bike? When I turn it to "stop" in reality it is on...and to reserve it seems as though it is "reserve". Although I have not run the tank out, why I know the "on" position is ....OFF.... is because I ran around a while, and my bike died. Then when I turned the petcock to stop...she fired right back up. Any input would be awesome, if only for me to brainstorm the problem. I just bought this awesome bike and rebuilt the petcocks. Don't think you can mess up there, but maybe I put them back wrong.....

 

[gbobst]

This is a 1972 Yamaha xs 650.......

 

[angus67]

not sure...but i think you have dual petcocks.
if you rebuilt them both together, you may have switched the face plates?

 

[gbobst]

yes...indeed dual, but both labels are the same no matter how you mix and match'em.....

 

[fullercameron]

They look right to me. I also have a 72 and they are both the same and turn opposite directions to turn on. On mine, the short end of the lever points at whatever function is selected. In your pics, yours appear to be open. Like I said when mine are off they face opposite directions. Left side would have the short part pointing forward, right side backward for off position.

 

[fullercameron]

What I just realized is if you rebuilt them, you may have the whizzer valve in turned - I think if you put it in with the closed position in the wrong spot, it will make it so the tags are useless. I believe that there is only one closed hole on the rubber valve and that is the stop position.

 

[gbobst]

Didn't think about that...I took both apart and should have kept one for closer inspection of the re-build....I will check that since it is easy to remove the tank, thanks man....makes sense.

 

[XSLeo]

It could be you are thinking about what part of the handle points toward the words. On my 75 the long arm points to the words. Right over them.My 75 the lever in the position in your first pic is on. If I turn it to the position shown in pic 2 it's off. It won't turn to pic 3. It turns to point up to get reserve.
Straight back is off, turn down to on, or up for reserve.
On yours, I would say pic 1 is off, turn the lever back is reserve, forward is on. As long as you know which is which then I see no problem.
If you have one pointing back and one pointing fortward you may have one put together wrong.
The rubber "whizzer valve has no control over flow, the groove in the flat part of the lever controls flow, the rubber part just seals the petcock.
If you take one apart you will see the body of the petcock has 3 holes. One for on, one for reserve, one to the outlet. The rubber has four holes, the lever has the groove. With the lever in the on position the groove links the on hole to the outlet. In the reserve it lines up the rreserve to the outlet. In off no holes line up.
The rubber parts can be put in in several positions so as it wears you can rotate or flip it so unworn areas can be used.
Leo.

 

[gbobst]

I think Im going to take the tank off and figure this out....will check back...thanks for the input all

 

[fullercameron]

Leo

Your right. Now that I think about it the valve does have 4 holes. I remembered that there was something that only had 3 positions, and it is the metal body of the petcock.

Straight down is on for the 72 petcocks. Not sure why, but I see 3 pics with the lever in the open position in all of them.

 

[XSLeo]

In looking at the pics, the plate behind the lever with the positions marked on it is different than mine. It has a nub sticking down at the top to act as a stop for the lever On mine this nub is toward the rear.
I haven't seen a 72 inperson so I can't be sure if those are stock petcocks or not, but as I said as long as they work and you know the positions, does it really matter.
Leo

 

[gbobst]

Thanks all.....just going to live with it. I now know what is what!

 

[irristeve]

the part that you turn on the valve ie lever is marked left & right have you got these right try swaping them around good luck