over fueling

[baz]

All the best for the coming year everyone
Anyone know what causes no 4 cyl on my z900 a4 to miss fire and the plug
is allways wet ???
The comp is ok and iv'e try'd new plugs !!!!
Could it be over fueling on that cyl ??

[PAULJAC47]

Could be a number of things,Bad ht or cap or plug,float level too high,mixture wrong,needle height,passing choke plunger seal try those first..Paul J

[baz]

thanks paul
ive swapped leads and caps, tried new plugs still the same, must be a carb fault i think.
what causes a carb to over fuel ???

[PAULJAC47]

Some causes in my last past Baz.

[nicomkii]

Exactly same issue on No.3 cylinder. I took out carbs, stripped and cleaned with a good quality aerosol Carb cleaning product, Swapped the Choke plungers around and reassembled. Bike is running smooth as, no lag in any area and a good burn on the plugs.

[baz]

It was fine when it was parked up last spring, never got out on it 😞
What's in the carb that can cause that prob ?

[PAULJAC47]

In addition to things already pointed out may be something simple such as a float stuck down,just a matter of methodically checking..

[Steve Cooke]

Float valve not sealing?

[Steve Cooke]

Needle valve not sealing?

[johny brando]

All the best for the coming year everyone
Anyone know what causes no 4 cyl on my z900 a4 to miss fire and the plug
is allways wet ???
The comp is ok and iv'e try'd new plugs !!!!
Could it be over fueling on that cyl ??

It could be a float valve with a poor seat/seal but you'd expect to then see it dumping the excess fuel to atmosphere. Get the bike upright . Turn the fuel on then off after say 5 minute .....this to prime float chambers then via the carb drain screws, drain & capture the contents of each float bowl & measure or compare the volume of fuel from each bowl. Then you can zoom in on that or dismiss it ! If it's all good swap coils or caps around & plugs.
Cheers Johny B