79 gs850 petcock OFF??

[Rob Arther]

so, am i suppose to shut the gass OFF when i park?? everyone is tellin me yes..so i look at my petcock, its been on the ON position. No leaks no nothin..so i turn it to the position that looks like "PRK"..park? after doing this for a while, theres fuel leaking into my air box down the side of my bike..do i just leave it on ON?? is PRK actually say PRM meaning prime?? please help!! i hink i need a new petcock now.

rob

[tone]

on or reserve IS off untill you start the engine & the vacum opens the tap the other setting is PRI prime which is a constant flow dont leave it there or you will fill your sump with fuel

[Rob Arther]

i think its been dumpin in, but even now when its on the "ON" position, theres a drop hangin from the bottom of it..i think im gonna pick up the rebuild kit..i dont think i need a new petcock but do you advise it? i kinda think it might be a waste unless the rebuild kits are ****ty

rob

[tone]

sorry i cant personally advise on the rebuild kits as ive only ever had a problem with one tap & just replaced it with one from my parts bin :-D

i'm sure some of the other members will be along shortly to advise :-D

[Dave8338]

i think its been dumpin in, but even now when its on the "ON" position, theres a drop hangin from the bottom of it..i think im gonna pick up the rebuild kit..i dont think i need a new petcock but do you advise it? i kinda think it might be a waste unless the rebuild kits are ****ty

rob

Hey...you said it, not me. :-D Buy a new one and forget about it for as long as you plan on owning the bike IMHO!!!!!!!!!

[Steve]

Chances are that you don't need a rebuild kit or a new petcock. \\/

If you left it in the PRIME position and you have fuel in the airbox, you have leaky float valves in the carbs, not a bad petcock.

As mentioned above, the petcock should not flow any fuel when left in the ON or REServe positions.

By the way, there is a PARK position on the ignition switch. Don't use that, either. :shock:
At least, not for very long. Turning the key to the PARK position turns on the tail light so your bike is more visible (until the battery runs down, which won't be very long).


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[BassCliff]

My daily profound glimpse into the obvious

Mr. Rob Arther,

To reiterate, the GS petcocks do not have an "OFF" position. They are vacuum operated. In the "ON" or "RESERVE" position they will not let gas flow unless the motor is started and creating a vacuum to open the valve mechanism. By putting the petcock on the "PRIME" position, you are opening the valve and letting the gas flow without the need for vacuum actuation. I always leave my petcock in the "ON" position. (Did I say really say that?) :razz:

If you've left it in the "PRIME" position for very long, there is a possibility that gas has leaked through the carbs and into your crankcase. If there is gas in your oil, be sure to change the oil before you ride.

Thank you for your indulgence,

BassCliff

[trdhrdr007]

If you left it in the PRIME position and you have fuel in the airbox, you have leaky float valves in the carbs, not a bad petcock.

As mentioned above, the petcock should not flow any fuel when left in the ON or REServe positions.

This has been discussed before, & in theory I agree 100%. However, I went outside one morning to go for a ride & had fuel dripping out of the airbox. When I started taking off the tank I realized my petcock had failed, & was delivering gas continously in any position.

I figured the float should stop the gas flow & that it was either coincidence that the petcock had failed, or that trash from the failed petcock clogged up the needle valve. So, while I was waiting for the new petcock, I pulled the carbs (which I had completely rebuilt a month before), disassembled them & thoroughly cleaned everything.

I put it all back together without the air cleaner, & still had gas leaking out the back of the carb. So, I repeated the process with the same result. By this time my new petcock arrived, so I installed it & hooked the tank back up. This time there wasn't any gas leak.

I'm not saying the petcock was, or wasn't the problem. Logic tells me that the floats should have stopped the fuel flow irregardless. However, my problem wasn't fixed until I replaced the petcock.

[Rob Arther]

well, its on the "on" position right now and i guess what i'll do tomarrow is disconnect the hose and see if gas flows out in each position to see if the vaccuum is workin. i really hope that all this was started because i kept putting it in the PRIME position all those nights..dammit! should i really change the oil? ive gone on many rides since and seems no prob yet.

--sep prob just arrose. so i turn the key and i hear a click, next thing i know, headlights and taillights work, no turn signals, no gas guage, whhhaaaaaa?? any hints before i go look up the wire diagram?

Rob

[Steve]

Check the second fuse from the top in the fuse panel.


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[psyguy]

I figured the float should stop the gas flow

my understanding is that the float needles ALONE cannot hold the gas pressure from the tank and would therefore eventually leak (although not necessarily immediately)
if the foat needles were sufficient i suspect the petcock would only need to have the "on/off" positions and would not need to be vacuum operated

[Rob Arther]

im gonna go check the fuse right now...the fuse panel is under the gas tank? ir right up front?

[psyguy]

im gonna go check the fuse right now...the fuse panel is under the gas tank? ir right up front?

i think you'll find them under the plastic side cover (mine is a 1980)

[vicloia]

1983 gs850 petcock

can anyone tell me what position is what on this bike's petcock.i have no idea which position is on or off or what,i got the bike for free with no manual and dont know any thing about the bike8-[

[psyguy]

can anyone tell me what position is what on this bike's petcock.i have no idea which position is on or off or what,i got the bike for free with no manual and dont know any thing about the bike8-[

don't you want to ask this in a NEW thread?