fuel leak from overflow tubes

[indyblue]

On my FJ it would piss out gas after I parked. Turned out to be gas leaking around the o-ringsof the plastic holders that hold the screens for gas input to carbs. Float height and cut off valve were good but those o-rings were drier than a popcorn fart. $22 kit from R.P.M fixed me right up.

This is what's happening to me, after I park it leaks.
My petcock has 3 positions, Off, Prime, and On.  (You can just barely see the "F" of OFF on top)

I do not believe you have a three position petcock. If you look closely the letters you are referring at the top are "EL" the last two letters of "FUEL". The FJ1100 petcock is two positions as already mentioned; PRI (prime) and ON. The PRI (prime) function is too fill the carb bowls if you work on them or run out of gas.

The "ON" is the normal operating function. The fuel flow is control by the vacuum diaphragm & o-ring inside of the petcock. That is what the petcock rebuild kit you bought from me is designed to replace.

If you look very closely at the edge of the lever you can see an arrow. That arrow in that position is pointed straight down indicating the petcock is in the "ON" position.

You can see the arrow very clearly on the new petcock here just under the "FUEL" lettering cast into the lever.

So which O-rings do I need?  I believe the needles/floats are holding and it is leaking in the Off position.  If it were the o-rings to the carb input, why would it leak if my petcock if OFF ( I could understand a few drips after shutting off as the bowl level goes down)?

You have a couple of options for carb o-rings; A complete carb o-ring and S/S allen head screw kit, a full carb o-ring kit or just the needle seat o-ring kit. You can see them by clicking the links below.

FJ11-12/XJ12/XJR13 S/S Screw & O-Ring Carburetor Kit
FJ11-12/XJ12/XJR13 O-Ring Carburetor Kit
Needle Seat O-Ring Set

BTW, the parts finder on my local dealers website shows a petcock available, it has a superceeded part # on it:
   https://www.partshark.com/oemparts/p/yamaha/36y-24500-01-00/fuel-cock-assembly-1

Get thee a new petcock, and be safe and change your oil. Even a teaspoon of fuel will breakdown the oil.
If you buy from RPM the petcock will already be safety wired. Randy does not fuck around with this issue.
http://rpmracingca.com/proddetail.asp?prod=M%2FC%3A36Y-24500-01

Cheers. Pat

As Pat already mentioned above as well, the new Yamaha petcock is available from RPM. By comparing the link to your local dealer website, you will save a few bucks buying it from RPM. Plus you will get the benefit of the petcock elbow being safety wired when you buy on from me. Plus, it is in stock and can be shipped to you in just a couple of days time. No waiting a week or more from the dealer.

Here is again is the link to the 85/85 FJ1100 Petcock:

84-85 Yamaha Fuel Tank Petcock


If, by chance, your petcock does say "OFF" on the top of the petcock, I would like to see that so I can make some inquiries on what petcock that might be.

Randy - RPM

What is the large o-ring that comes with the diaphragm kit for?  My factory service manual nor the Yamaha microfiche does not break down the petcock assembly.  I already have a new petcock to tank oval gasket o-ring.