Serious CARB problem

[rynr]

I did everything what i thought that would help and it didn't.

Here's the problem: on every fuel cock position: PRI, ON, RES the fuel runs through the carb and floods the spark plug.

When spark plug isn't flooded i try to turn engine on and it's running but after half of minute more-less fuel floods the spark plug. When I disconnect both hoses from cock (vacuum and fuel) flooding fuel starts to burn the engine also starts running.

Tried different sparks, new valve assy and needle.

Also I've got european version which has richer carb (as alantf said) so maybe i do something wrong with vacuum hose?

Or maybe niddle, jet, is to lossy in holder?

I have got fuel in oil inside engine because it went to airbox so high and reached hose for oil drain (when to much oil is in the engine)

According to parts manual, my carb is a slightly different than this one shown.



Hope, you guys have some ideas what went wrong, because I'm out of them.

[alantf]

Sounds like the float (in the carb) has gone faulty.

[mrlmd1]

On ON and RESERVE no fuel should be flowing unless the engine is running, to supply vacuum to the petcock. Is that true with your bike or is fuel flowing out of the tank no matter the petcock position? That could be one problem.

What do you mean "When I disconnect both hoses from cock (vacuum and fuel) flooding fuel starts to burn the engine also starts running."? Do you mean the engine will run for a short while on the fuel already in the carb bowl? That is normal.
What valve assembly and needle did you replace?

Two possibilities are - The float could be stuck or saturated with fuel (defective now), or the needle valve could be dirty and leaking. Try a good dose of carb cleaner directly into the carb, let it soak a while, and also into the gas to see if it helps before taking the carb apart for a good inspection and cleaning.
And you need an oil and filter change. Don't run the bike with gas in the oil.

[rynr]

Petcock works fine, carb was disconnected from bike for general cleaning, before that it worked not very effective but it worked. Needle valve is new.

"When I disconnect both hoses from cock (vacuum and fuel) flooding fuel starts to burn the engine also starts running."
I tried to tell that too much fuel goes to engine and when in carb is partly empty it's possible to start the engine.

I just bought another carb (gz250 is not very popular in my country so it's better to buy when it's available) and we'll see what's going on .

I did FLOAT HEIGHT ADJUSTMENT and helped a little, i was able to ride around for a minute . I don't know if i did it precisely.

Which option shown on picture is correct A or B? Original picture from manual on page 111 isn't very precisely :/

[Water Warrior 2]

I would think "B" would be a more precise measurement.

[Road_Clam]

Originally Posted by rynr

I did everything what i thought that would help and it didn't.

Here's the problem: on every fuel cock position: PRI, ON, RES the fuel runs through the carb and floods the spark plug.

When spark plug isn't flooded i try to turn engine on and it's running but after half of minute more-less fuel floods the spark plug. When I disconnect both hoses from cock (vacuum and fuel) flooding fuel starts to burn the engine also starts running.

Tried different sparks, new valve assy and needle.

Also I've got european version which has richer carb (as alantf said) so maybe i do something wrong with vacuum hose?

Or maybe niddle, jet, is to lossy in holder?

I have got fuel in oil inside engine because it went to airbox so high and reached hose for oil drain (when to much oil is in the engine)

According to parts manual, my carb is a slightly different than this one shown.



Hope, you guys have some ideas what went wrong, because I'm out of them.

Sounds like your choke plunger is stuck slightly open. This will allow additional raw fuel to the engine. I seriously doubt if you have an incorrect "jetting" issue. Like others commented if you have a faulty float that is absorbing fuel, that will cause flooding as well.

[rynr]

I really don't know what was the problem. I connected another CARB from GZ250'2003 and it works fine. I checked everything that you said could be faulty and everything looks ok. I think problem might be in lossy jet niddle in holder, but as long as second carb is running well i don't have to know if i'm right