Fuel leak from air filter

how fix the tube to the drain?

The most likely reason for an overflow is the float valves are not working properly. Did you remove the floats and needles and inspect all the parts carefully? Replace all the carb O-rings? As the others have said, do the clear tube test.

LineArtist wrote: If you have a vacuum petcock the diaphragm is possibly torn allowing more gas to flow into the carbs (and out). To check, disconnect and remove the air hose from the petcock and smell/inspect it for traces of gasoline.

Check your float bowls first using the clear tube test (as mentioned)
Check all fuel lines for leaks

I don't understand what is leaking inside your airbox???

On some models fuel can overflow into the carb throat and run back into the air box. Also, if there is a tear in the petcock diaphragm, fuel can flow down the vacuum hose into the carb.
Fox needs to test the petcock to see if it is stopping the flow on ON and RES. if not, it needs to be disassembled, cleaned and all the rubber bits need to be replaced. Then he needs to carefully inspect and reclean the float valves and inspect the overflow tubes, if present. Then clear tube test for fuel level. Of course all the gaskets and o-rings should have been replaced with new.

Fox wrote: how fix the tube to the drain?

There is no need to worry about this until the other thingshave been adressed, and only then after you have confirmed that one or more of the tubes are broken.

Hello,

1/ Petcock seems to be good. When i turn it ON the fuel go down from the 2 valves in the same time and stop on OFF position : www.google.com/search?q=kz1000+petcock&c...rc=9-DvaRwlwYvEJM%3A

2/ I rebuild the carbs, adjust floats as it was (from memory)
3/ I put the carbs at horizontal, (like it's positionned on the motorcyle,) put fuel in the tubes, and it don't leak to air box like that.
So floats seems to work.
If i tilt the carbs to left or right, the fuel piss from the bottom center tubes (the one near the drain screw).
Is it normal???
Fuel go out from my 2nd carb in first...

Fox wrote: 2/ I rebuild the carbs, adjust floats as it was (from memory)
3/ I put the carbs at horizontal, (like it's positionned on the motorcyle,) put fuel in the tubes, and it don't leak to air box like that.
So floats seems to work.
If i tilt the carbs to left or right, the fuel piss from the bottom center tubes (the one near the drain screw).
Is it normal???
Fuel go out from my 2nd carb in first...

No, not normal unless you tilted the carbs an extreme amount.

Have you done the clear tube test yet?

It will be next work.
i need to find a solution to keep the tubes in place on the drain screew holes...

If you have tubing that will fit into the holes, you can screw it in for a good seal.
Steve

Yesterday i decide to clean my carbs because i had the 2 troubles :

_ need to open the petcock 10 minutes before start the engine or the motorcycle don't start. Start well after those 10 minutes.
_ When i ride, the engine stop when i down a hill... need to send gaz to don't stop.

Floats ???

Hello,

Ok i did the float Level Check with an installatin like this one
All carbs at levels at the center (3mm) and all was good.

I rebuild the KZ and then same problem.
Fuel leak from my 2nd carb.

I think that would be good if my motorcycle was the central stand... but it was on the lateral stand.
So leak from the inclined side.

I place the clear tubes directly on the carbs on the motorcycle to check levels.
Alls are wrong because the motorcycle is not verticall.
The 2nd carb is really high.

The bike must be level.
Steve