odd overflow problem

[sidecardad]

I have an 81 gs650l.and carb 1&2 are overflowing. I have replaced the float valves and carbs are clean. I have exchanged the needle and seat, float, and bowls with different carbs and 1&2 still overflow and the others do not. When i drain the bowls 1 has almost no fuel and 2 is half full. No leaks, cant find any cracks. When the carbs are upside down on the bench the valves seal well enough you cant blow through the gas line. I'm stumped. Thanks for any help.

[barnbiketom]

make sure you have the bowl vents open. not connected to each other.

theres ports on the sides of the carbs that should have SEPARATE LINES

[tom203]

Overflowing into airbox ?? have you check your petcock fo correct operation? so it's not putting constant pressure on needle valves when bike is off? Are you a kickstand user?

[sidecardad]

The carbs are off the bike. I have a new radiator overflow tank and a shut off valve i'm using on the bench. The tank is above the carbs about the same height it would be on the bike. The hoses are on the vents and the carbs are bolted together. I've been using this setup since I started working on them. I don't have an airbox, the bike came with pods. When I turn the gas on it streams out the small port on the back of the carb.

[chef1366]

If it is the right port (main air jet) then your jet needle is not blocking the main jet and your float height is not set right.
Did you put new o-rings on the inlet valves?

[sidecardad]

The floats are set at.880, tried .920 even. How can i tell if the jets are working right. The gas is flowing out the small hole in the back, not the one with the jet screwed in it. I can blow air in the small hole and it come out in the bowl through the needle jet.The orings are new. If i take the bowls off I can stop the flow by moving the float up. Thanks again for the replies and help, it's appreciated.

[barnbiketom]

we can assume the fuel is going INTO the correct place right?

Reason I ask i I've 'rescued' 4 or 5 bikes the PO had the fuel lines hooked up all wrong.

pics might help

[BassCliff]

Greetings and Salutations!!

Hi Mr. sidecardad,

Welcome to the forum.

Let's start with this:
Overflowing Carbs

You'll want to make sure all the maintenance is up to par. This means properly cleaning and rebuilding the carbs (see the guides on my little website), cleaning all the electrical connections and testing the charging system, replacing ALL the fluids (brake fluid too), making sure the brakes and tires are in good working order. Rebuilding the master cylinders and calipers, replacing the brake lines, etc, is all good stuff. You'll find a complete list in the "mega-welcome" below. Here's the S.W.A.G.

If you are here you probably have a 30 year old motorcycle that needs about 20 years worth of maintenance. You'll find all kinds of helpful tips, procedures, manuals, etc, in the links below. Let's get started.

Let me dump a TON of information on you and share some GS lovin'.

I just stopped by to welcome you to the forum in my own, special way.

If there's anything you'd like to know about the Suzuki GS model bikes, and most others actually, you've come to the right place. There's a lot of knowledge and experience here in the community. Come on in and let me say "HOoooowwwDY!"....

Here is your very own magical, mystical, mythical, mind-expanding "mega-welcome". Please take notice of the "Top 10 Common Issues", "Top 15 Tips For GS Happiness", the Carb Cleanup Series, and the Stator Papers. All of these tasks must be addressed in order to have a safe, reliable machine. This is what NOT to do: Top 10 Newbie Mistakes. Now let me roll out the welcome mat for you...



Please Click Here For Your Mega-Welcome, chock full of tips, suggestions, links to vendors, and other information. Then feel free to visit my little BikeCliff website where I've been collecting the wisdom of this generous community. Don't forget, we like pictures! Not you, your bike!

Thanks for joining us. Keep us informed.

Thank you for your indulgence,

BassCliff

[sidecardad]

Yes, Fuel is going into the bowls. The fuel passage is clear of obstructions.If the needle jet dosent seat fully will fuel over flow? I had the jets and tubes out when i cleaned the carbs. the emulsion tubes are seated fully in the groove. Maybe I have something together wrong. I'll try and take some pictures tommorrow for reference.

[Steve]

we can assume the fuel is going INTO the correct place right?

Reason I ask i I've 'rescued' 4 or 5 bikes the PO had the fuel lines hooked up all wrong.

Yes, Fuel is going into the bowls.

Oh, even if you put fuel in the wrong port, it will still end up in the bowl.

It is possible to put fuel into the VENT port on the side of the carb, as it is quite close to the FUEL port, and will not be controlled by the float valve. In fact, it will simply tend to drain the tank and flood the floor.

.

[barnbiketom]

It is possible to put fuel into the VENT port on the side of the carb, as it is quite close to the FUEL port, and will not be controlled by the float valve. In fact, it will simply tend to drain the tank and flood the floor.

.

that is exactly what i said only i kept it simple

[sidecardad]

There is one tee fitting for the fuel inlet right? Two tee fittings for the vents right? The fuel inlet is lower on the side of the carb than the vent. Looking at the back of the carbs, fuel is coming out the hole on the right. When I hook up the gas line with the carbs on the work bench and the bowls off I can stop the fuel by raising the floats with my finger. That tells me I have the gas line in the right place.

[tom203]

There is one tee fitting for the fuel inlet right? Two tee fittings for the vents right? The fuel inlet is lower on the side of the carb than the vent. .....

Yes,
If it shuts off by raising float with finger, but not by gas filling bowl,....Hmm, do your floats float?

[sidecardad]

I just went out in the garage to take some pics. Put the bowls back on, hooked up the gas lines and no leaks, What gives?

[barnbiketom]

must have been dirt in the seats??

A few times I got dirt simply by pushing on old crappy cruddy partially disintegrated fuel lines.

I always replace 'em with blue poly.

maybe you flushed out the seats while testing with the bowls off!!!!!!