Fuel cock leaking

[SausageNips]

I'm having an issue with the right angled piece that comes off of the lower part of the fuel cock being loose and leaking.  I took it off and examined it (please see attached photo).  There is a groove on the part that goes into the fuel cock assembly - is there an o-ring that belongs there to keep it in place?  Does anyone know what size it is?

Thank you!

[Pat Conlon]

No O ring, it's just a press fit. A bad design. If it falls out while you are riding, you're in deep doo doo.
That's why we tell folks to safety wire this elbow to the petcock body.
See my signature line.

You can use a sealant but be sure you get the angle correct on the elbow.

Cheers

[SausageNips]

Thank you so much!

[balky1]

Did anyone ever try to weld it (is it aluminum?) or solder it?

[Pat Conlon]

Not that I'm aware.

[FJ_Hooligan]

I tried using threadlocker once but it didn't work.

[Pat Conlon]

...You can use a sealant but be sure you get the angle correct on the elbow.

Just to be clear: You can add a dab of sealant, but it is NO SUBSTITUTION for safety wiring the elbow.

[racerrad8]

I have not tried to solder, but I did try and TIG weld. The fitting is a "pot metal" that will not weld.

There have been a couple of people who have used some form of epoxy to reinstall the elbow. The problem with that is, if the epoxy fails, you could end up with a bike that gets burned to the ground.

Twist Tie Those Petcocks Folks!

Or

Re: '84 to '87 Petcocks: Safety wire your petcock. Do it now or asap!

Here are links for both versions of the new petcocks.

84-85 Yamaha Fuel Tank Petcock
86-88 Yamaha Fuel Tank Petcock

Remember the petcocks, if original, on your FJ are thirty plus years old. You buy a new one and you can possibly get another 30 years of service from it. It is like an insurance policy to cover you from a fire.

Randy - RPM

[SausageNips]

I bought a new aftermarket petcock with a shim plate and it installed very nicely (exact fit).  It no longer contains a diaphragm, so the small air hose has no where to connect to.  Can i just leave that or do I need to cap it off?

[big r]

Needs to be capped off. It is a vacuum line will suck air if not blocked. Big R

[FJmonkey]

Capping off the vacuum line to the petcock will stop the fuel flow on 84 to 87 FJs. I am not saying don't do it. But if you want fuel to flow to the carbs then fix the petcock or find an alternate solution.

[racerrad8]

Monkey if he got the pingle from us with the adapter there is no vacuum port to the petcock. I believe he is talking about capping the intake manifold side. Which must be done when running the pingle or else you will have a vacuum leak where the oem petcock vacuum line goes into the manifold.

Robert - RPM

[FJmonkey]

Yes, capping off the petcock vs. capping off the vacuum port on the intake boot. If the petcock is no longer with a vacuum port then cap off the port at the intake boot.

Thanks for the clarification Robert.