Petcock Question Again

[PAULYBOY]

I assume my 82 GS850 has a petcock with a vacuum hose coming out. However, I don't see it. I'm pretty sure last year when I painted the tank I reinstalled everytghing that came off. Could it have disappeared? And, where does the other end hook up? I don't see anything clearly in my Haynes manual. Guess I should have bought a Clymers, huh?

[PAULYBOY]

Oh, one more thing. I did go over some of the threads from the search under petcock. I'm guessing that illustrated bike info is not quite up to the standards I'm used to selling Mercedes parts. Mercedes is finally up to 21st century standards when it comes to parts and tech info available online. Best I can find on bikes is sketchy , inadequate copies of old microfiche illustrations.

[twr1776]

Do you still have the OEM petcock? If I am not mistaken the vacuum line from the petcock needs to be hooked up or the bike will not draw fuel from the tank. My line goes from the back of the petcock to a nipple in between carbs # 1 & # 2 for the vacuum. I have CV carbs which I believe you do as well.

[PAULYBOY]

Hey, thanx for the reply. I'll lokk tonite when I get home if it's before dark and see if there's a connection. Due to my lysdexia LOL , I'm assuming carb #1 is on the left as you're sitting on the bike looking ahead. My bike does run, I just noticed yesterday when I was helping my 20 YO with it that there was an extra ? port on the petcock that looked like it sholud have a hose. Right now, there's only 1 hose i can see hooked up, and thats definitely fuel.

[ptm]

It will still run without the vacuum hose, but only if you have it set to PIRme. That setting allows fuel to flow all the time - whether the engine is running or not. If it's on ON or REServe, it flows fuel only when there's a vacuum.

[BassCliff]

Couple of pix

Hi Mr. PAULYBOY,

You are correct, the #1 carb is on the left as you sit on the bike. Have a look....




The smaller hose on top is the vacuum line. The larger hose is the fuel line. The fuel line will connect to the nipple between the #2 and #3 carb on the back side of the rack. You can see it in the picture below. The pencil is pointing to the vacuum nipple.




Thank you for your indulgence,

BassCliff

[PAULYBOY]

Cliff, I looked closely at your pix. The hose nipple showing at the carb rack has a hose coming from it. I traced this hose to a nipple coming from the left underside of my tank about 2/3 of the way up towars the front on the underside. I can see a nipple or port on the petcock facing forward in your pic, the one your notes say has the vacuum line going to it. I guess my questions now are these-
1. I've put more miles on the bike after replacing the freshly painted flames, becaus of a 2 week period whre my truck wasn't working. The bike for awhile last September was a daily rider. It worked so well (except for the fuel gauge that I forgot to reconnect) that I ran it out of gas twice.
2. That having been said, the 1st time it ran out of gas, I remember changing it to reserve and leaving it there.
3. If I reconnect the hose to the vacuum port of the petcock, then what goes to the other port in the tank?

Oh, and, yes, it is the original petcock, not a replacement.

[BassCliff]

I hope I explain this right

Hi Mr. PAULYBOY,

If your rig is like mine, the two nipples from the petcock (vacuum and fuel) should connect to the corresponding nipples on the carb rack. The other hose coming from the tank is the vent hose connected to the fuel gauge send unit on the underside of the tank. This hose should be routed down behind the airbox and pointed at the ground.

There are also two vent hoses coming from the carbs (from between #1 and #2 and from between #3 and #4) which also get routed behind the airbox. In the above pictures, you see a black nipple directly between the #1 and #2 carbs.

Note that in the picture above we are looking at the side of the carb rack which faces the head. If your petcock is passing gas without the vacuum line connected, then I would suspect you have a bad petcock.

I hope I haven't confused the issue. Maybe this will help:



Thank you for your indulgence,

BassCliff

[PAULYBOY]

Okay, Cliff. finally got warm enough and dry enough outside this weekend to try and get some work done. Here's what I found. (First off, let me preamble by saying that I'm typing this at work because my laptop has a possibly fatal worm that I've spent a total of 17 hours trying to fix, and it AIN'T WORKIN'). Sorry I didn't want to upload any pix from my worm infested laptop, but this is what I've found. My petcock looks almost identical to yours. The fuel hose is attached correctly, with a mini inline filter about 2 inches along. The other nipple on the petcock is unattached.
The hose that comes out of the nipple next to #2 carb in your picture runs up and forward to the underside of the left hand side of the tank. If you're sitting on the bike and feel along the left side of the tank about even with where the "SUZUKI" logo is attached, that's where this nipple is. So, the short story is that even though there clearly is an open nipple at the petcock, there aren't anymore places for another hose to go.

[BassCliff]

Hi Mr. PAULYBOY,

I'm sorry I can't visualize your description very well. Are you running a stock petcock and carb setup? It sounds like the vacuum line from the #2 carb is not connected to your petcock, for some reason. But I don't know what else it could be connected to. Have you had the tank off to verify all of the hose routing? (Don't forget to disconnect the fuel gauge wires - I ripped my apart recently and had to re-splice.) Let me describe my stock 850 setup. Maybe it will help you.

Check out this similar thread. It might have some useful info.

You have two connections on the petcock. The larger one is for fuel, the smaller one is for vacuum. Connect both petcock ports to the corresponding ports on the carb rack. The fuel line goes to the carb rack fuel port between carbs #2 and #3. The vacuum line goes to the vacuum port on the front of carb #2. Reference the pictures and descriptions above.

There is a hose coming from the fuel gauge send unit on the underside of the gas tank. This hose gets routed over and behind the airbox and gets pointed toward the ground. This is just a vent hose.

There are two other vent hoses from the carb rack. They connect to the vent ports, one port between carbs #1 and #2, and one port between carbs #3 and #4. These two vent hoses run over and behind the airbox to stay out of turbulent air. All of the vent hoses are connected only at the "business" end and are left open on the other end, no connection.

There is one more hose under there, the breather hose. It connects the breather port on top of the valve cover to the corresponding port on the top of the airbox.

Between the pictures in this thread and those in the other thread, you should be able to get everything connected properly. Let me know. I can snap a couple more pictured if you want me to. "Have camera, will wrench." :-D


Thank you for your indulgence,

BassCliff

[PAULYBOY]

Cliff, let me say firstly, as far as paople in general and certainly the "anonymous citizenry of the internet", you would be the by far the top votegetter of the Saint of the Internet award.
As for the problem at hand, now that you've shed more light on other possibilities, I'll have to take a look tonite before the next round of precipitous deluge begins. We're expecting another super soaker in the Ohio valley, starting either tonite or possibly tomorrow. As far as I know, the tank and petcock are both original. As you may remember, not long after I first joined, and you had a stunning pic of your 850 with the "brownish" paint, I sent you a message that my bike was the same exact model from the factory. even the color. That's why I'm glad you responded to my thread in the first place. Keep in mind, however that I've put a couple hendred miles on my bike after I painted the flames and reinstalled the tank.

[BassCliff]

The Patty Duke Show?

Hi Mr. PAULYBOY,

I appreciate your patience with me. If I recall correctly, the 1982 850G came in "brown". Mine is a 1980 and is more "maroon-ish" but looks kind of brown in the right light. But still, the bikes should be close enough to be identical cousins (remember that show?). Anyway, take another look when you get a chance and perhaps we can get the connections sorted out.

Thank you for your indulgence,

BassCliff

[Steve]

I assume my 82 GS850 has a petcock with a vacuum hose coming out. However, I don't see it. I'm pretty sure last year when I painted the tank I reinstalled everytghing that came off. Could it have disappeared? And, where does the other end hook up? I don't see anything clearly in my Haynes manual. Guess I should have bought a Clymers, huh?

Since we got my son's 850 a couple of weeks ago, I am now blessed with all three manuals, Clymer, Haynes, and Suzuki. \\/

Have not read through the Haynes manual much yet, but the closest I can find for your hose location problem is on page 91, figure 2.4. There is a hose sticking up from the engine side of carb #2 that has no number. That is the one that should be attached to the smaller nipple on your petcock.

From your description, it sounds like your vacuum hose is connected to the drain port for the fuel level sending unit. That is the only other thing under the tank that has a hose nipple on it. That should have a hose that reaches back, over the airbox, then down toward the swingarm pivot and opens to the air. It is there just in case the sending unit gasket has a leak, the hose will direct any fuel away from the hot engine.

BassCliff has given you good pics and text, so you should have no problem getting it straight.

Do you still have the OEM petcock? If I am not mistaken the vacuum line from the petcock needs to be hooked up or the bike will not draw fuel from the tank. My line goes from the back of the petcock to a nipple in between carbs # 1 & # 2 for the vacuum. I have CV carbs which I believe you do as well.

TWR, if your petcock is connected to the nipple between carbs 1&2, your bike is not connected properly, either.

The nipple between 1&2 should have a matching nipple between 3&4, and these are both vent fittings for the float bowls. The hoses attached to them should lead over the airbox and usually end under the seat in non-turbulent air. The vacuum supply for the petcock should come from a nipple on the engine side of the #2 carb.

.

[basic]

from the sound of where the hose from vacuum line on carb number 2 that Bcliff provided, I'm going to agree that it sounds like this line is running to the hose nipple on the gas level sending unit. There should be a hose on the cover of the fuel level sending unit that goes to open air, just as a precaution of a leaking seal. The line that goes from Number 2 carb should be the one that connects to the petcock.

[BassCliff]

Another pic

Thanks Mr. Steve and Mr. basic. Here's another picture that I "touched up".



What do you think?

Thank you for your indulgence,

BassCliff