Gas continues to flow thru petcock in ON and RESERVE position, even when bike is off

[medicinalmotorcycle]

I just took my petcock apart, cleaned it up, put it back together, but now it is like it is in the prime position no matter what position it is in. Gas keeps on flowing thru the petcock in the ON and RESERVE position even when the bike is off and no vacuum is being created. So now I can't shut the fuel off when the bike is parked, or have gas flow from a vacuum. It didn't do this before I took it apart, so I must have put it back together wrong, or torn a gasket or something but am not sure. Any ideas?

[doctorgonzo]

Either or, not back together right, or bad/torn diaphragm.

[Dogma]

Either or, not back together right, or bad/torn diaphragm.

Shouldn't it shut off, regardless of the diaphragm's condition? In mine, there was a seal on the end of a pin, which was spring-loaded to shut off the fuel. If that seal and spring are there and good, then it shouldn't flow. If the diaphragm is bad, that would make it not flow, or allow fuel into the vacuum side (rich fouled #2 plug) if it is intact enough to open the petcock.

[doctorgonzo]

Shouldn't it shut off, regardless of the diaphragm's condition? In mine, there was a seal on the end of a pin, which was spring-loaded to shut off the fuel. If that seal and spring are there and good, then it shouldn't flow. If the diaphragm is bad, that would make it not flow, or allow fuel into the vacuum side (rich fouled #2 plug) if it is intact enough to open the petcock.

You could be right, when mine went bad, it flowed all the time, but I didn't tear it down, just replaced it. I just rattled off a quick answer. Bottom line, it's buggered in some fashion, make sure it's together right.

[Dogma]

You could be right, when mine went bad, it flowed all the time, but I didn't tear it down, just replaced it. I just rattled off a quick answer. Bottom line, it's buggered in some fashion, make sure it's together right.

Yeah, definitely somethin' wrong.

[Bill Lloyd]

New petcock

Several times I've read in these threads about replacing a petcock with a new one. I've seen posts with references to places to buy them and when I go there, there are no such things shown as available. WHERE does one get a new vacuum-operated petcock for a GS850G or a GS1100G?

-- Bill

[chef1366]

Several times I've read in these threads about replacing a petcock with a new one. I've seen posts with references to places to buy them and when I go there, there are no such things shown as available. WHERE does one get a new vacuum-operated petcock for a GS850G or a GS1100G?

-- Bill

What year?

[emeraldcoupe]

i just ordered one for my 81 550t from the local suzuki dealer, pn 44300-45372 so they are available

[Dogma]

Several times I've read in these threads about replacing a petcock with a new one. I've seen posts with references to places to buy them and when I go there, there are no such things shown as available. WHERE does one get a new vacuum-operated petcock for a GS850G or a GS1100G?

-- Bill

I've ordered new ones for two different 850 years now from Z1Enterprises. IIRC, I had to search on petcock, instead of looking for the specific model first.

Like so.

[Billy Ricks]

There is the flat rod, for want of a better term, with a loop of spring built into on the diaphram side of the petcock that pushes on the diaphram in the prime position to allow fuel to flow. You likely have it extended too far causing it to push on the diaphram at all times. Try adjusting the length of it to make it flow only in the prime position. If you make it too short you won't have a prime function, too long and it will always be on prime.

[SqDancerLynn1]

There is the flat rod, for want of a better term, with a loop of spring built into on the diaphram side of the petcock that pushes on the diaphram in the prime position to allow fuel to flow. You likely have it extended too far causing it to push on the diaphram at all times. Try adjusting the length of it to make it flow only in the prime position. If you make it too short you won't have a prime function, too long and it will always be on prime.

If you have this type of petcock through it in the trash and get a universal one from Z1enterprises.com about $45 the repair kits sell for almost $30 so why take the chance

[en12gine]

petcock problem

I know that I have had the same problem with mine, even though it's a 97. I took it apart and cleaned it and the same thing continued. Went ahead and bit the bullet and ordered a new one. Everything is fine. Sleeping better at night now. Just a suggestion.

Craig