Topic: CB550 K3 PD carbs float level

[-CB-Jamie-]

So my dad picked up a CB550K3 two weeks ago. Bike is in pretty good condition cosmetically but has only been used on and off in the last ten years.

So I stripped the carbs and ultrasonically cleaned them, put them back together with new o-rings etc..

I set the float levels to 14.5mm per the manual. Put them back on the bike and turned on the petrol and had no problems with overflowing petrol and ran the bike for a while.

I just wanted to double check the float levels using the clear tube method after I had carbs back on the bike. So I put clear tube onto the overflow pipe on one carb and opened the drain screw. I then turned on the petrol and petrol flowed into the tube but kept rising up the tube and kept going until reaching the height of the fuel in the petrol tank.

Proceeded to check the next carb and same issue even though none of them overflow when the drain screw is closed.

Am I missing something here?
Should I be able to check the level using clear tube on these carbs?
Or will it not work as the drain screw releases the petrol through the overflow pipe?
I just cannot see why the petrol would continue to flow up the clear tube when that's connected yet none are overflowing??? 

Jamie

[flybox1]

the floats are not shutting off gas as they should.   remove the carbs, and check float valve function.
perform your clear tube test with the carbs on the bench connected to an aux fuel source, or, connected to the tank with carbs lower than tank level.

[-CB-Jamie-]

That's the thing the floats are shutting off the gas as none of them are actually overflowing when the clear tube isn't connected and the drain screws closed. Also the bike actually ran pretty good, I was only doing this to double check the levels!

Also I took one of the outermost bowls off and pushed up the float by hand and it is shutting off the gas alright!

[flybox1]

if the floats do their job, the gas flow should stop.
perform the clear tube test on #4 or #1, be sure to secure the tube to the carbs.  it should be untouched.
as you crack open up the bowl drain screw, take a block of wood or a rubber mallet and gently tap the carb backplate...might keep the float from sticking open...