Carbs leak into airbox when on side stand

[Big Red]

Ok so i put everything back together filled the bowls and added more then #4 was leaking this time. so i drained that one bowl and removed it. held the float up with my finger and added fuel. this time it continued to leak into the where the bowl would be. (uh oh). i have since drained all the bowls. next step will be to remove float and needle and seat to see if something is sitting wrong or broken. does anyone have tips on removing the seat as i always have troubles????

[chuck hahn]

Be sure the floats are in the right way too. Theres a bent tang at a 90 degree that rests against one of the float posts..be sure you can see it when the float is installed.

Needles may look fine but the brass float seats can be worn and leak past the needles.

Be sure the gaskets arent hitting on the floats as you move them up and down.

Be sure the float pins arent bent..these can make a float hang up a well.

Be sure there are gaskets between the float seats and the carb body..if not theres a leak situation area.

If you have metal floats take them and shake them next to your ear to listen for liquid inside them sloshing. This signals a leaking float which will keep the fuel on no matter what.

If you have poly carbonate floats theres no weighted float issues.

To remove the seats..DO NOT SQUEEZE them with pliers. This can make them ever so slightly out of round and the float needles will drag and then your screwed. Remove them by using a GENTLE grip and a twisting and pulling motion as low on them as you can grab. I use my hemostats and once theres a little gap between them and the carb body a thin blade screw driver will extract them. Use a prying motion and dont twist the blade and make gouges in the surfaces. A little WD40 will lube the orings and help too.

If youve already did the pliers grip be sure the recess for the needles are round and the needles will spin 360 when inside the holes. If they dont spin around inside there and not drag or hang up youve got it out of round...This may be your problem.

[azr]

"To remove the seats..DO NOT SQUEEZE them with pliers. This can make them ever so slightly out of round and the float needles will drag and then your screwed. Remove them by using a GENTLE grip and a twisting and pulling motionas low on them as you can grab. I use my hemostats and once theres a little gap between them and the carb body a thin blade screw driver will extract them. Use a prying motion and dont twist the blade and mke gouges in the surfaces. A little WD40 will lube the orings and help too.

If youve already did the pliers grip be sure the recess for the needles are round and the needles will spin 360 when inside the holes. If they dont spin around inside there and not drag or hang up youve got it out of round...This may be your problem."


Good tip Chuck.

[BillGS550LZ]

If I were you I'll get a new set of o-rings for the needle seats in any event but specially if you've ever used carb cleaner to clean carb passages with the seats installed. Btw/Hard to tell condition of rings by looking but if you notice allot of seat play once the clamps are removed then they are toast for sure.

[Big Red]

all the orings were replaced last winter when i did an over haul on the carbs. the seat have no play in them at all in fact that is why i have not tried to remove them yet. getting warmer this week so i will be doing some more work on them later in the week.got them back together again and the same thing is still happening again now. leaking when on an angle. the big float/needle issue is fixed. (i guess i was tired when i put it back to gether last time i had the needle upside down) oops. it seems the the fuel is coming out of the pilot air jet of carb one.

[JTGS850GL]

Gas can not be overflowing and coming out anywhere unless the float valve is leaking or misadjusted. Your petcock is leaking as well if it's has a vacuum line.

Do as Steve indicated... Change out your float valve and seats as a pair. For the price, I'd replace all 4 at one time and be done with it. No reason to frustrate over $40 in parts.

[Big Red]

during my current testing i am just feeding the fuel into the fuel line from a kids medicine syringe. the petcock has nothing to do with the current equation. I am going to do a test on the needle again this week by holding the float up with the bowl off then add fuel again to see if it leaks. if yes then i will start replacing the seats.

[JTGS850GL]

By holding the floats up you may not prove anything. It should take very little pressure to shut off fuel flow. Pressing more then the float is exerting will make the fuel flow stop but it will still leak under normal float pressure.

You may also want to verify that the float still "floats". Submerge the float in water and verify that it floats properly. If it sinks then it’s saturated and bad. Usually they float fairly level with the metal pieces slightly submerged.

How are you verifying float height? Are you doing it without the gasket in place or out?

This should not be a huge issue to resolve. Either the seat is not seating, the o-ring around the seat is leaking or the float height is incorrect. There can’t be anything else unless your bike is leaning WAY over on the side stand. Way over like it's almost going to fall over.

A new seat and needle assembly costs $10 from PartsnMore. That's $10 each for piece of mind or to completely rule that out.

[Big Red]

ok so funny thing last night i have only had the carb bank in a vise on my bench with an open ended fuel line and no vacuum hose attached. leaking pretty quickly once the bowl are full. so i thought i would try something new i put the vacuum hose on and put a nail in it to plug it add some fuel into the line i can see it staying in the line like normal. then i also plugged the end of the fuel line. normally i would go away and come back in 20 min and the line would be empty with a little leak out of carb one. with the hoses plugged the fuel was still in the line after two hours. but empty this morning. but i did play with the nail plugging the vacuum hose last night.

[Big Red]

For the new seats and needles does anyone know of a Canadian supplier.

[JTGS850GL]

The reason for no leaking with the hoses plugged is because there was no place for the air to enter to compensate for the displaced fuel in the line. It's like holding your finger over a straw filled with water. The water stays in the straw until you remove your finger.

Yep you still have a leaking float so it's time to replace them. Here's where I bought mine, and they are in Canada:

Parts N More

Here's a link for your bike: GS550L at Parts N More

[Phred]

I notice that you are in Ottawa. If you want to use my sonic cleaner to really clean the carbs out , you are welcome to bring them over sometime. I used the chem dip the first time and was amazed at how much more came out after sonic cleaning them. Had the same problem with fuel in the air box.

[platinum2]

try getting all new needle and seats and oem o rings! the aftermarket junk can shrink in a year, and the diaphragm on the pet cock can go bad and leak in to the carbs as well , try cyclepartsnation for o e m stuff, when the bike is on the side stand it will leak out of the no1 most likely because the gas is filling up that bowl all the time and if everything is working from the tank to the bowls the carbs will build up pressure , "like in the gas tank" and it has to go some where! so it heads to the most wore needle and seat first

im assuming the tank has no "off" on the petcock, "pri,on res"? some how the tank is building pressure and pushing gas to the bowls, i went through 2 petcocks that were bad, and that wore out the needles and seats
hope this helps