1979 GS1000SN replacement petcock. where?

[Guest]

Where can i get a good, but not original(to expensive) petcock for my 79GS1000SN? Z-1 i suppose, but they don't list it for this bike, any other suggestions? it's the vacuum style.Thanks!

[Suzuki_Don]

Ring Z1 and talk to them. Thery have a lot more parts available than what they list on their website. When ordering a petcock the main dimension is the distance between the holes centres. these vary on the GS models. I bought one from them for around $40 I think it was.

[chuck hahn]

The face that you see looking at the bike is the same as many others..such as the 77 and 78 750s. The nipples are in different angles though. If the hole spacing is good and the nipples arent touching anything it will work also.

[fishnetter]

Ok folks;

Can someone give me a quick answer here. On the petcock rebuild kit I purchased, the diaphragm has 2 rubber gaskets(square, 1 with the small hole). are these supposed to come apart, and one goes on each side of the spacer? because mine are together, and I can't seem to separate them at the metal center piece. if they come apart, do I have to pry them apart. Ai don't want to damage them, but I think that's why I have a leak. The spacer is right up against the back plate of the petcock, and that's where it's leaking. I'm working on this now, and want to get it done before it gets to hot here. Thanks!

[sedelen]

Ok folks;

Can someone give me a quick answer here. On the petcock rebuild kit I purchased, the diaphragm has 2 rubber gaskets(square, 1 with the small hole). are these supposed to come apart, and one goes on each side of the spacer? because mine are together, and I can't seem to separate them at the metal center piece. if they come apart, do I have to pry them apart. Ai don't want to damage them, but I think that's why I have a leak. The spacer is right up against the back plate of the petcock, and that's where it's leaking. I'm working on this now, and want to get it done before it gets to hot here. Thanks!

They are not supposed to come apart, but you work one side very carefully through the spacer hole, make sure the recessed area around the hole in the spacer block faces to the outside. The diaphram half with the little O ring goes to the inside. Line all the spacer block little hole with the inner diaphram little hole, to the little hole (which should be unclogged, very small) that leads to the outside of the petcock (close to
the upper right backplate screw as you look at the petcock from the front. Use lots of lubricant (WD-40) tighten those backplate screws very carefully allowing the diaphram assembly to find it's own center without any pressure.

[fishnetter]

Thanks. before your response, the lite bulb in my head turned on, and I figured that out finally! the only problem is when I put the back plate on, lining up all the small holes, the vacuum nipple & the fuel line nipple, cross right in frond of each other, so I can't hook both hoses up, because they're to close to each other. so I turned the back plate 90 degrees, where the nipple for the vacuum, is now at the bottom. I now have NO fuel leak. The issue now is when this bike came apart 15 years ago, I had the carbs rebuilt, and now that the bike is running, it acts like it's starving for fuel, but, the carbs need to be balanced, and a general tune-up check. It has new plugs, but it is defiantly not running right. I don't know about the issue with the petcock nipples in front of each other when the small hole are all lined up. I don't remember it being that way all the years I've had it before the teardown to replace the stator, regulator/rectifier! Now I need to find someone in the central valley of California near the Modesto/Stockton area that is good, and will work on this bike and get it straightened out. then it goes up for sale. hate to let her go after 32 years of ownership. I bought it new 4th of July weekend in 1979. so this weekend it will be 32 years ago I bought it new. Wow! anyone out there around my area know a mechanic that will work on her? Thanks!

[sedelen]

Thanks. before your response, the lite bulb in my head turned on, and I figured that out finally! the only problem is when I put the back plate on, lining up all the small holes, the vacuum nipple & the fuel line nipple, cross right in frond of each other, so I can't hook both hoses up, because they're to close to each other. so I turned the back plate 90 degrees, where the nipple for the vacuum, is now at the bottom. I now have NO fuel leak. The issue now is when this bike came apart 15 years ago, I had the carbs rebuilt, and now that the bike is running, it acts like it's starving for fuel, but, the carbs need to be balanced, and a general tune-up check. It has new plugs, but it is defiantly not running right. I don't know about the issue with the petcock nipples in front of each other when the small hole are all lined up. I don't remember it being that way all the years I've had it before the teardown to replace the stator, regulator/rectifier! Now I need to find someone in the central valley of California near the Modesto/Stockton area that is good, and will work on this bike and get it straightened out. then it goes up for sale. hate to let her go after 32 years of ownership. I bought it new 4th of July weekend in 1979. so this weekend it will be 32 years ago I bought it new. Wow! anyone out there around my area know a mechanic that will work on her? Thanks!

What? Going to let her go! The GS1000SN, that is the Wes Cooley model isn't it? If it is you shouldn't have any problem selling it. Now about that petcock, answered your other thread thinking I was telling you how to repair a GS1000E or C. Then I saw this thread and saw the GS1000SN, was hoping it had the same petcock and I didn't give you some lousy advice.
You can remove the backplate, and rotate it separately from the diaphram/spacer block assembly so that the vacuum nipple is at say 10 o'clock as you look at the front of the petcock. Remember all those little holes need to line up to each other and to the hole opposite the petcock backplate on the upper right of the petcock as you face the front.

There's some real GS1000 superstars in California, no doubt you'll probably be hearing from them.

[fishnetter]

Yeap, it's a Wes Cooley. now, has i stated, if i line all the little holes up on the inside of the petcock, to the diaphram, and then the spacer, and then the back plate, the vacuum nipple will cross directly in front of the fuel nipple, and i can't get the hoses on without rubbing on each other. so i turned the back plate 90 degrees, and the vacuum nipple is now on the bottom, but the back plate hole is not lined up now with the rest of the little holes on the other items. i took it for a short ride up & down my street, and it acts like its starving for fuel. the carbs were rebuilt, so they need to be balanced first. then the timing has to be set, and the rest of everything else checked for accuracy. then we'll see how it runs after all that. if it still acts like it's not getting enough fuel, then i'll look back into the alignment of the holes on the petcock.
When i put the petcock in the "pri" position, it seems to run a bit better for a few moments,then not, so i switched over to the "on" position, add seems to run a bit better for a short time, then it acts like it's needing more fuel again. i just need someone to balance the carbs, check out the timing,and all other tune-up things, and then see how it runs. but i can tell you, it isn't easy finding someone out here that can work on this bike, and has a carb balancing tool. i used to, not any more. i hope someone chimes in here with a name soon. 15 years down, and i got it running again today.now it just needs to get straightened out the rest of the way. should be easy stuff though! Thanks for any help anyone can give!!

[sedelen]

The hole I'm talking about is not on the back plate, on my petcocks it's on the front plate if you will, on the gas nipple side, it's on the main part of the petcock. I have 3 petcocks and they all have it. Is that the hole your talking about? You should be able to keep that and the diaphram/spacer holes lined up and just rotate the back plate. I believe that is the way it's suppose to be and needs to be to get that vacuum nipple opposite the fuel line nipple.

If your bike seems like its starving for fuel, there's a vent hole in the gas tank filler neck, on the right side, make sure it isn't clogged.
Also, your gas cap, it's vented, it could be clogged, it's vented through the bottom of the cap and goes to this little cylinder inside the black piece with the parts that lock. It has holes with ball bearings inside that provide a gravity seal, from there it feeds between the top stainless steel cover and the bottom part of the cover and vents where it's crimped and up underneath that black seal. Does the bike run better with the gas cap off?

[fishnetter]

Haven't tried it yet with the cap off. the carbs really need to get balanced first, and the timing checked also, then I can go from there. I'll try running it with the cap off later tonite after it cools down. don't like riding it with the cap off, but there's only about a gallon and a half in the tank now.

[sedelen]

Haven't tried it yet with the cap off. the carbs really need to get balanced first, and the timing checked also, then I can go from there. I'll try running it with the cap off later tonite after it cools down. don't like riding it with the cap off, but there's only about a gallon and a half in the tank now.

Riding it with the cap off? Maybe you can just loosen it a little. If you run it in Prime, that's gravity free flow, bypasses the vacuum petcock opening, just make sure you turn it back to on when you park it, otherwise you may have gas overflowing your carbs when it's not running.

[chuck hahn]

Dibs Please if you sell it......And of course PM me as many pics as you can. Thanks for the consideration..

[fishnetter]

Well, I got it running! the lite bulb finally went on in my head on how to get the petcock together properly, buy, the bike acts like it's starving for fuel. when I took it apart 15 years ago, I took the carbs off, and had them rebuilt. so I know they need to be balanced and tuned, before anything else happens. so I found a gent that will work on it, so I'm taking it to him next week.
I think it will be an easy fix, at least I'm hoping so! it has to be between the carbs & petcock, or both.don't think theres an electrical issue. it just doesn't want to throttle up when you get on it. time will tell. I'll post the outcome when it gets figured out. Thanks for all your help. it really helped me get it back together. 15 years apart! Man, I'm thrilled!!