Topic: Gas leaking down line. Please advise.

[slkern]

When I turn the petcock to ON, I have gas leaking down from one of the lines where it enters the carburetor. I just replaced the line itself to see whether it was damaged, but there's still a leak. I was wondering if anyone had any ideas or advice on how to move forward? I have a 1972 CB750 K2.

Thanks,
S

[tlbranth]

Where the line hooks on to the carb there's a tee. That tee enters 2 carbs and each entry is sealed with an o-ring. You might have a bad o-ring.

[bryanj]

Actually 2 orings each side so 4 per tee

[Kevin D]

I just replaced the line itself

What kind of line did you use?
My K1 works best with 5.5mm, not 1/4"

[MauiK3]

Yes, the 5.5 mm line is the way to go, other lines don't work well.

[ekpent]

 If the line fits tight it could be one of the brass nipples that comes out of the petcock may not be fully seated. It is not rare to try and pull off a fuel line and also pull that brass nipple out of the petcock with it.If it leaks there gently tap and re-seat the brass nipple back in tight.
  Of course the best thing is to try and find the exact source of the leak first. Taking off the tank and mounting a couple of plugged fuel lines would be easy. If the fuel tee's need new o-ring the leak is coming from between the carb bodies.

[slkern]

I used a 5.5mm line. I'll try replacing those o-rings to see if that does the trick and report back here in time. Thanks!