I've had my hands on only afew GS's so maybe its experience. My understanding has been the Reserve outlet is typically longer. Thats how my main GS is as well.

This one has the Reserve outlet as the shorter nipple.

I think its a relevant thing to clear up as some people tell useres struggling with problems that the longer nipple on the tank petcock goes to reserve.. and if they had this petcock that would be incorrect.

Thanks for any insight.

This is from a 91 GS I had been putting back together and am about wrapped up with.

That's an odd duck alright.   A couple questions:

• Have you tested it, and confirmed that the shorter outlet drains longer than the other one?  (That's what I would expect, if it is an OEM GS500 petcock ... which has the same part number for all model years.)
• Are the 2 outlets labeled with a stamped letter? ('R' or 'O')

I've never tried it, but I wonder if it's possible to remove and switch the outlets.  Perhaps an overzealous mechanic got confused by the parts fiche diagram and tried to "fix" the petcock? 

Quote from: Kerry on July 20, 2013, 06:19:07 AM
That's an odd duck alright.   A couple questions:

• Have you tested it, and confirmed that the shorter outlet drains longer than the other one?  (That's what I would expect, if it is an OEM GS500 petcock ... which has the same part number for all model years.)
• Are the 2 outlets labeled with a stamped letter? ('R' or 'O')

I've never tried it, but I wonder if it's possible to remove and switch the outlets.  Perhaps an overzealous mechanic got confused by the parts fiche diagram and tried to "fix" the petcock? 

Yeah thats what I am worried about.. I get a drop (ever so slight) from this petcock after its installed. I have just bought new screws and a new tank to petcock gasket. I am also attempting to replace the gaseket inside the petcock itself as the old one was dried out..

If I get all those orings done and it still drips (untested yet) then I will begin to wonder if someone had pulled and swapped the nipples.. although with inspection it does not to appear to have been done..

I assumed the flow was correct but I will check before reinstall and get some more pictures. This will be Sunday (tomorrow) when I post those additional pictures.

I was starting to think maybe it was due to me not having enough hands on with GS's and maybe I missed a year it was switched.. but depending on what we find out the safe saying of the "longer nipple is reserve" may not be able to be said.

Quote from: Kerry on July 20, 2013, 06:19:07 AM

I've never tried it, but I wonder if it's possible to remove and switch the outlets.

Yes it is possible. I have done this.

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Look at the filter screen. The tubes are in there.
You can see which one is longer. That's the MAIN or ON one.
The short one is reserve.
I do not believe the screen can be installed backwards. However the brass tubes can get pulled out and then put back in wrong.

It would be a good idea to remove the metal clip and the valve assembly and replace the o-ring with a fresh one (if you haven't done that already). Bad o-ring will cause fuel drips.

Quote from: adidasguy on July 20, 2013, 11:48:31 AM
Look at the filter screen. The tubes are in there.
You can see which one is longer. That's the MAIN or ON one.
The short one is reserve.
I do not believe the screen can be installed backwards. However the brass tubes can get pulled out and then put back in wrong.

It would be a good idea to remove the metal clip and the valve assembly and replace the o-ring with a fresh one (if you haven't done that already). Bad o-ring will cause fuel drips.

Quote from: adidasguy on July 20, 2013, 11:48:31 AM
Look at the filter screen. The tubes are in there.
You can see which one is longer. That's the MAIN or ON one.
The short one is reserve.
I do not believe the screen can be installed backwards. However the brass tubes can get pulled out and then put back in wrong.

It would be a good idea to remove the metal clip and the valve assembly and replace the o-ring with a fresh one (if you haven't done that already). Bad o-ring will cause fuel drips.

Believe it or not its been difficult finding that oring locally. Its not on the parts fiche either.

Ok update.

The long tube is on the correct side.

Question the nipple, if its pulled, is it hooked to the tube or is it just a nipple?

Here are some pictures


Replaced the oring as well.