GS1100L #2 carb leaking, bike wont start.

[cowb0y]

The #2 carb on my GS1100L is dripping gas out the air box side. She wont start and I noticed gas dripping from the lowest portion of my exhaust (middle underneath the bike) when I tried to start the bike last. So I figured the floats needed adjustment. I removed the air box and filter (all stock) and set the floats at 22.4 mm each. After installation, the bike still wont start. Only #2 and 3 have any gas in the bowls. #1 and 4 are dry. After a few cranks, gas starts dripping out the back (air box side) of #2 carb, which can be easily seen since the air box was left off this time. I am not sure what to do now.

Some history: I have installed an inline fuel filter with new fuel and vent lines and throughly cleaned the carbs. My tank is stock and has some rust in it. I had a tuff time finding a replacement tank and so went this route since this is my commuter bike and I am tryin not to sink a bunch of money in it rite now. The vent line that connects #2 carb with the petcock has gas in it and I dont remember seein it like this in the past. I am thinkin the inline fuel filter is the cause of my problems, but I have read several posts where fellas are using them. So, I am asking you guys what you think.

Thanks,
Jess

 

[Nessism]

If there is fuel in the vacuum line your petcock is junk and needs to be replaced. You will also have to deal with the rust in the tank, a fuel filter is not an appropriate solution.

 

[Guest]

Take off the tank and get some evapo-rust. Let the evapo-rust sit in the tank overnight. Pour out.
Put some gas and nuts and bolts in the tank and shake the tank. Drain the gas and repeat until the rust is gone.
If this doesn't work get a product called POR-15 or Kreem to line the tank.

If you don't take the carbs completely apart there is a little shelf at the fuel rail in each carb that will collect the rust and your bike will never run right till you remove it.
Make sure to use a gravity fed filter like lawnmowers and tractors use. 5/16" size

 

[cowb0y]

Can you treat the gas tank with the fuel sending unit still inside? My tank has already been Kreened by the previous owner, but its started to fail recently.
The inline fuel filter was purchased from a bike shop and is in a 'L' shape with a gold stone in the middle as the filtering agent. Would think affect the gravity feed in some way??
I did use the 5/16th inch size fuel hoses and filter, but did not completely remove the fuel and vent connectors in the carbs, which is what I will do this next weekend and see what happens. Guess I am in need of a new petcock as well.
You guys are always a great resource and I truly appreciate it. :clap:

 

[Guest]

You will ruin the sending unit if you don't remove it.
Posplayr made a plate from an old unit, taped the petcock hole and the fuel cap hole.
I would use the nuts and bolts method to loosen up that old sealer.

 

[cowb0y]

So, I tore the carbs apart and nothing blocking the fuel lines, but there were a few small rust flakes in under the needle valve seat. All is clean now. I checked the inline fuel filter and no flakes in it. Curious. I now have a clean tank, so no more rust.
I wanted the eliminate all my problems one by one, so here's what I have done so far: I checked the compression in each cylinder via the spark plug port. All are 120 plus or minus 2lbs. I believe this is good right??
Next, I put five to six drops of good, clean, new fuel in each port and installed the spark plugs, then pushed the starter for about 10 seconds. No fire. No starting. I have spark indicators inline with my spark plugs and I think they might be robbing some juice from the plugs, but all showed spark going to the plugs.
It started raining hard, so I stopped trouble shooting for the day. My next step is to figure out if my spark is strong enough under compression. How do I do that? I know the trick of grounding a spark plug to the case and watching the spark, but how will I know if its enough to start the bike?

 

[Guest]

Just a thought, I see other people with leaky petcocks woorying about fuel in the crankcase... Is this an issue for the L version? I realize that it isn't the problem but could be a problem when it does start... just a thought...

 

[Nessism]

The vent line that connects #2 carb with the petcock has gas in it and I dont remember seein it like this in the past.
Thanks,
Jess

Jess,

Did you deal with this problem yet?

 

[Surfpilot]

Sounds like the first thing you should do is rebuild your petcock. Then clean clean clean your carbs. I've also heard of some people having problems with the inline filters. Take it out and see if it runs without it. You may be creating a pressure problem.

 

[cowb0y]

I realize that it isn't the problem but could be a problem when it does start... just a thought...

Belluci, yes it could be a big problem. I have read that the gas in the exhaust pipes could ignite and blow the pipes off! Not sure thats true, but I dont want to find out.

 

[cowb0y]

Jess,

Did you deal with this problem yet?

I think I am, but this neophyte isnt sure. I have come across a new (clean) tank that I am using now and I found a step by step troubleshooting procedure from a link on GSR. Thats why I did the compression testing, then put gas in the spark plug ports, etc. This method is supposed to eliminate erroneous issues that arent stopping the bike starting, I believe. My true goal is the get the bike to run for longer than 2 minutes (the max of all of 2009!).

 

[cowb0y]

Sounds like the first thing you should do is rebuild your petcock. Then clean clean clean your carbs. I've also heard of some people having problems with the inline filters. Take it out and see if it runs without it. You may be creating a pressure problem.

I am curious about the pressure problem also. Do any of the sage GSR's know of any possible pressure issues related to inline filters??

 

[cowb0y]

Jess,

Did you deal with this problem yet?

You will ruin the sending unit if you don't remove it.
Posplayr made a plate from an old unit, taped the petcock hole and the fuel cap hole.
I would use the nuts and bolts method to loosen up that old sealer.

How do I remove the gas mixture from the tank without destroying the paintjob?? This has been an issue in the past when I tried pouring it out the petcock hole, the gas cap hole and the sending unit hole (which did the least amount of damage).

 

[Larry D]

Carefully. I don't think there is a good way. Just be careful and try not to splash it everywhere.

Sounds like your fuel system needs a good overhaul. Start by getting the tank as clean on the inside as you possibly can. If your petcock is suspect, BUY A NEW ONE and don't worry about it for +-20 years. Lose the filter, the petcock filter, if clean, is suficient for your filtering needs. Get new fuel and vacuum lines....just so everything is new. You said you cleaned the carbs...how...by the recommended method on this site ? Did you disassemble, dip them and install new orings ?

One more....is your gas cap clean ? It needs to breathe.

 

[1948man]

How do I remove the gas mixture from the tank without destroying the paintjob?? This has been an issue in the past when I tried pouring it out the petcock hole, the gas cap hole and the sending unit hole (which did the least amount of damage).

If you remove the tank and set the petcock to the "Prime" position (if your model has the prime position), I think the gas would flow out the line from the petcock into a gas can or other vessel.

 

[mike_of_bbg]

Did you swap the old petcock with the new tank (or did you just clean the tank you had)? There's a diaphragm in the OEM petcock which allows fuel to flow only when vacuum is being applied. If that diaphragm develops a leak, fuel will leak through the vacuum line into carb #2. That's the only reason there should be fuel in the vacuum line. Your response to Ed was not confidence inspiring. Rebuilding petcocks gets mixed reviews so to +1 Larry D it's best to buy new and not worry about it again for 20 years.

AFTER you have determined the petcock is no longer a problem, check for gas in the crank case and change the oil even if you don't smell it, just to be sure. The gas is thinning out the oil and can lead to bearing damage as well as clutch slippage. Fuel in the exhaust sounds like a bad thing too, since the combustion mixture tends to leave the head still on fire

New plugs cost about $8 and are worthwhile investment. See if you can borrow an inductive timing light somewhere and make sure you're sparking at/near the right time. Take the spark indicators off to prevent losing juice to the plugs.

Your compression numbers are fine - but is there any air coming in at idle? Are you cracking the throttle when you try to start? What about applying the choke? +1 did you DIP the carbs for 24 hours each and put new o-rings in? Did you bench sync the carbs when you were done? Check your new plugs for wetness from fuel. They should be a little wet (and uniformly so) if it's not burning what's coming in.

 

[cowb0y]

Ok, the tank is new (to me) and clean inside. However, this tank is a bit bigger (length) and so I am in the process of making a bracket to hold the tank on. The front gromets need to be a bit higher, but the bolt hole in the rear lines up well; I'll just need a longer bolt.

The carbs have been cleaned and bench synced (so the PO tells me) with stage 3 dyna jets and has pods that came with it. I have confirmed spark at each spark plug is thick and blue, except #1. So I am gonna replace it and maybe all the others too.

I do smell gas in the oil. How does it get there? I will change it as suggested. Where would i get the o-rings if I where to need them in the future?

My buddy suggested a hand-pump syphon to get the gas out and it worked!! I filtered the gas out jus to see what I could catch and I will post a pic of the crap that came out of my tank. Its crazy.

Thanks for all the comments fellas.

 

[Guest]

http://www.cycleorings.com/

The fuel gets into the oil a few ways.
A bad petcock
Bad inlet valve o-rings
Bad float needle and seats

 

[cowb0y]

If the compression is good, does that nessarily mean the inlet valve o-rings are good??

 

[gggGary]

It sounds like you are fighting several battles yet. The O rings that seal the float valves to the carb body are notorious leakers and should always be replaced at carb overhaul. This guy sells the o-rings very good and reasonable.
http://cycleorings.com/
When you have the valve seat bodies out if you look in the hole you will see an o-ring and a screen up in there, that screen will need most likely need cleaning. with all the screens out lots of carb cleaner through the passages should flush out the rest of the rust.
The gas leaks through the carb, pools at the intake valve runs into the cylinder and washes the oil off the cylinder wall and rings and contaminates your sump oil, none of that is good for your engine. In severe cases a cylinder full of gas can bend a rod when the piston tries to compress non- compressible liquid gasoline.
here is a photo of a valve body removal tool I made from a hole gauge. I just ground the ball to be a snug fit inside the body. tighten the handle and withdraw the valve body.Much better than messing up the body with needle nose pliers.