Petcock related? Vacuum Related? Both?

[7mJoe]

I finally got my bike all back together and running. Yesterday I fired it up for the first time in about a year and it sounded awesome! Only problem was that it only ran for about 30 seconds. So i started narrowing the problem down. I come to find it's the petcock. I have a vacuum block off on it and the #2 carb. So, after the initial start up it dies after what fuel it does get is used up.

My question is that if I unblock and run a hose to the #2 carb and the petcock would that do anything for me? Or should I just out right buy a new petcock? I'm asking before I do anything.

Not to mention the bike is very difficult to start, this morning I couldn't even get it to kick over, is this petcock related? Because I get nothing on On and Reserve, but I get it to go on Prime, then it goes up to 3k RPM and dies after about 30 seconds. Let me know what you guys think! Thanks.

[Dave8338]

Unless you're running the bike on PRIME...your fuel supply is only active with the vacuum line installed. Is there a reason (I'm sure the PO did it because the petcock is shot) you've got it unhooked?

[Big T]

I finally got my bike all back together and running. Yesterday I fired it up for the first time in about a year and it sounded awesome! Only problem was that it only ran for about 30 seconds. So i started narrowing the problem down. I come to find it's the petcock. I have a vacuum block off on it and the #2 carb. So, after the initial start up it dies after what fuel it does get is used up.

My question is that if I unblock and run a hose to the #2 carb and the petcock would that do anything for me? Or should I just out right buy a new petcock? I'm asking before I do anything.

Not to mention the bike is very difficult to start, this morning I couldn't even get it to kick over, is this petcock related? Because I get nothing on On and Reserve, but I get it to go on Prime, then it goes up to 3k RPM and dies after about 30 seconds. Let me know what you guys think! Thanks.

try the vacuum hose first, it's cheap and you'll know in a few seconds if it works

If you can't get it to kick over, I'm guessing you left the petcock on Prime and filled your cylinders with gas. Check your oil level, you may have filled the motor with gas. Pull your spark plugs and see if it will kick over then (with gas flying out of the plug holes)
If this happened, change the oil while you wait for the new petcock you ordered to show up.


On Prime, it should keep running until you run out of gas in the tank. Unhook the gas line from the petcock and hook up a drain line. Run the drain line into a can or bottle. Turn to Prime and see if gas comes out continuously

[7mJoe]

When I got the bike the holes were plugged, so there isn't a reason they are off. I had the bike on prime for about 30mins when i noticed some gas dripping so I put it to on. I got it to kick over but it's the same as I said, it doesn't run for long.

If I hook up the vacuum line it would work? If not then just buy a new petcock?

[BassCliff]

Hee Haw Howdy!

Hi Mr. 7mJoe,

Sorry, I missed what bike we are talking about. New petcocks are almost always recommended. No, they're not cheap. But replace it and don't worry about it for about 15 years. If I haven't given you my mega-welcome, then please stop by my little BikeCliff website and read up on all the Suzuki lovin' that I've been collecting. Click here to read the mega-welcome online. See the Where Do These Hoses Go? page for petcock/carb connection information.


Thanks for joining us. Keep us informed.


Thank you for your indulgence,

BassCliff

[80GS750]

i would hook the vacuum line up, if it doesnt work properly then, order a new one...

chances are someone blocked it off cause it doesnt work...

if you order one, i would get it from z1enterprises.com

those guys know their stuff, and they wont steal your wallet from you either

-nate

[Bill Lloyd]

Petcock

Just visited the Z1 site, they show NO new vacuum petcock[s] for '80 [at least] GS850G. Does Suzuki still offer these? [Fat chance, I suppose.]

-- Bill

[7mJoe]

I take it fuel isn't supposed to come out of the vacuum end of the petcock then? Because I got fuel everywhere now...

[Big T]

You are correct. Fuel should only come out of the (larger) fuel port on the petcock.

Check with your local dealer or one listed in the Megawelcome to see if the petcock is available.

That will solve some of your problems.

Have you checked for rust in the gas tank or clogging in your carbs yet?

[7mJoe]

I just POR-15ed my tank and sealed it so my tank is good. I just had my carbs rebuilt, but I'm not sure of that because the guys that I had do them couldn't figure out why my bike kept stalling... when it was the petcock:-?. But they seem to be in better shape then they were so I'll only know until I get it really running. The first cylinder carb fuel bowl leaks some though, but I'm not too worried.

Thanks for the help though guys, this site kicks ass. Does anyone know where I can get crash bars for my bike?

[7mJoe]

So I bought a new petock and I got it all hooked up and everything and now it won't start. I got it to slightly kick over, a few putters but that's it and I don't know why. It ran for only a few moments on the old petock and now that I have a new one with the whole vacuum port and everything, I can't get it to start.

I belive I have spark but if I don't how do I check? Thanks for the help!

[robertbarr]

Switch your petcock to anything BUT Prime. Get a small container (tuna can or some such) and open each carb drain screw. This will tell you two things: Is there fuel, and is it contaminated?

If there was fuel in all 4 bowls and it was clean, then switch your petcock to Prime, wait a minute or two, and give it a hand with some ether to get it fired up.

If there was no fuel (or just a small amount) you know there's a problem with your petcock. It's not too complicated.