HELP!!! Fuel everywhere

[CasiUSA]

SO my parents woke me up around 6:30 this morning telling me it reeks of gas in the garage and there's a wet spot under the bike. I don't have to be at work for another 2 hours, so I go to investigate. The airbos breather hose is leaking gas. I take everything apart and the airbox out. Carbs? Spewing out more gas. I undo the carbs. I turn them over and about a shotglass worth of gas comes out the sliders. Can anyone suggest what may be causing this problem? I am confused, and I have no idea why that much fuel would be overflowing in the carbs. Thanks. :x

[Kerry]

First, I'm betting that the arrow on your ON/RES/PRI fuel switch is pointing to the PRIme position.  Since your bike is a '92, this is probably UP:



When the switch is in the PRI position, fuel will flow from the tank because of gravity.  (The engine doesn't need to be running for fuel to flow, like it does in the ON and RES positions.)  In the PRI position, the only thing(s) keeping the fuel from flowing right through is/are the float needle(s).

Take at look at this picture of a carburetor rebuild kit from PartsNMore.com:



The float needle is the silver metal part.  When everything is installed, this fits tip-first into the brass part in the picture.  The brass part has a small hole in the center of the thick end.  Fuel flows through this hole into the float bowls unless the tiny rubber-looking tip on the float needle stops up the hole.

OK so far?

A problem like yours is usually caused by some gunk that has settled inside the brass part around the hole.  This prevents the black tip from fully stopping up the hole, and fuel slowly flows through the system until there isn't any more....

The fix?  First, try to clean the carbs.  This will include soaking that brass part (minus the O-ring) in carb cleaner for a while, and then blowing it out with compressed air.  Also, make sure the black tip on the float needle is looking "healthy".  It shouldn't be dry or cracked or coated with gunk or have a "ring" worn into it from years of service.  Anything that will keep it from sealing that hole is BAD.

If any of the parts you see in the rebuild kit look like they're in bad shape, your next step is to buy a rebuild kit before you put the carb back together.  (Follow the PartsNMore.com link above.)

EDIT: Changed link from sisna.com to bbburma.net

[Kerry]

Oops - it looks like I posted to the "wrong" copy of this thread....

[CasiUSA]

So I took the carbs out this morning, drained all the fuel out, and let everything sit all day so the gas could evaporate. I put everything back together, and now the bike isn't starting. Do you think the rebuild kit will remedy this? Thanks.

[Kerry]

The only way to know "for sure" is to take the carbs apart and inspect everything.  It's really not hard - just takes some time to do it in an organized way.  Do you have a manual?

You've already done the hardest part.  If you can unhook / remove / rehook the carbs and all the fuel hoses and cables, the rest is a piece of cake.

[Kerry]

Oh, and remember: one carb at a time!  Unless you're ULTRA organized, it's best to only have one set of parts floating around on the workbench...

I keep a stack of empty plastic apple sauce cups - the kind you pack in a lunch.  I line them up in two rows on my workbench, and as I take nuts and bolts off of the bike I put each item in the cup that matches the item's position on the bike: right front, left middle, etc.

For carb parts you could use one cup for TOP, another for INSIDE and another for BOTTOM (or something like that).  For small parts like that you can also just use an egg carton.  The cardboard kind would probably be best, given the incompatibility of styrofoam and gasoline or carb cleaner.

[CasiUSA]

Thanks Kerry, you've been really helpful.  

[CasiUSA]

OK, I took out the carbs, gave a thorough cleaning. I re-assembled everything, and the bike isn't starting. I know this is probably a stupid question, but what else should I do in order to start the bike. I just re-installed it, left the petcock on "On", pulled the choke down and it still wouldn't start. I also charged the battery while I was working on it, and when I first started it, a loud BANG happened. I assume that this is from the Hydrogen build up from the battery. Any help would be appreciated.

[Kerry]

After reinstalling a set of just-cleaned carbs, you actually NEED to put the petcock on PRI so the carbs can be "PRImed".  There's no fuel in the carbs, and you won't GET fuel into the carbs with the petcock on the ON or RES positions because the engine isn't running.

This is one of the few uses for the PRI position.  Turn it to PRI, wait 30 seconds or so for the float bowls to fill with fuel, then switch to ON and try to start the bike.

[CasiUSA]

OK, I did that and started the bike. It started, Idled roughly for a few minutes, and then died. I started it again, and the idle was sporadic, and it died when I tried to give it throttle. I adjusted the knob under the carbs to idle it at 1.5K, and when I throttled it, it went straight to 3K and stayed there and then died. While it was running, I noticed a sucking/ticking sound coming from the right cylinder. Afterwards, I took the plug out and it was fouled. The plug is new(Literally about a week old). I am so frustrated with this thing. I am thinking of selling it and buying a pony. Just kidding, but I am still frustrated.

[Kerry]

1) Plugs:  Is the plug carbon-fouled (dry, black) or fuel-fouled (wet, black)?  Either way, you sould be able to clean it up with a paper towel or shop cloth.  Oh, and the plugs are gapped correctly, right?

2) It can be tough to get the rubber "boots" reattached correctly on the carburetors - from the airbox and to the cylinders.  Are you sure they're on all the way, and screwed down tight?  Especially the ones between the carbs and the cylinders - if they're loose you could be getting less-restricted air and running lean (which can cause the high revs you're seeing).

3) When you turn the choke OFF (forward position) at the handlebar, the "linkage" on the carbs should return on its own.  I can't remember if you mentioned the action of that linkage bar - is it smooth, etc?  On one of my GS's the cable would get stuck and I had to hop off and push the linkage in by hand to turn the choke off.  Solution: I lubed the choke cable.

4) In one of your early posts you suspected that the bike was running on one cylinder, and the symptoms seemed to disappear when you replaced the plugs.  I don't mean to sound like I'm looking for something to hit with same old hammer, but did you do any of the electrical tests from the Narrowing down the problems to a broken bike thread that I mentioned back then?

Compared to the carb work you have already done, taking these measurements is easy and pretty non-invasive.  And it will give you either peace of mind, or knowledge of an electrical problem that needs looking into.

Read the whole 3-page thread before acting; the electrical stuff got more precisely spelled out towards the end of the 2nd page.  And on the 3rd page Von Vester made some fuel-related observations that sound pretty close to your symptoms.

[CasiUSA]

Well I gave it a thorough look, and score another one for Kerry . The cylinder with the fouling problem has a cracked bracket that connects the carb to the cylinder head. The part that the carb slides into and bolts onto the cylender head is cracked. The part where the tube and the flange meet is split, and probably causing this problem. Anyone know where I can get my hands on one of thse pieces, and how much they run? Thanks.

[Kerry]

Hmm.  I wonder if that was the "sucking" sound you mentioned?  It wouldn't explain the "ticking", but let's take care of one thing at a time.  

[Kerry]

See if this is what you're after.

Intake Pipe Assembly -- Part #21 on BikeBandit "Cylinder Head" diagram

If so, their price is $19.92 (at the bottom of the page).

[CasiUSA]

Well, that's the one. I'm assuming the ticking sound is the slides falling down when there's a lack of vacuum pressure as a result of this leak. Does that sound like a reasonable explanation?

As a sidenote, Kerry, you are awesome, If it weren't for you and your help, my baseball bat would have found my bike a long time ago.