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Carb woes...which goes where ?
NigeEss - 22/1/09 at 08:31 PM

Decided to get my bike going again, a Kwaka ZX550A4 that's been hidden under a pile
of sh... in the garage for over a year now. Fresh fuel, new battery and it fired but rough
as a bears arse and fuel leaking out of the carb over flow.
Stripped the carbs and cleaned them up, blew the jets etc but on reassembly I noticed the
emulsion tubes are not all the same. Two have four holes at the bottom and ten at the
top the other two have six at the bottom and four on top. Jets and needles all the same.

Obviously one pair will be for cylinders 1 & 4, other pair 2 & 3 and is probably to do
with cylinder temperatures. I'm thinking the ones with less holes at the top ( exposed
on wide throttle ) will give richer mixture and hence cooler for cyls 2 & 3.

Or I am I misunderstood emulsion tube function ? That is to atomise fuel with the correct amount of air.

Haynes was no help as were the guys at at Kawasaki centre.



[Edited on 22/1/09 by NigeEss]


idl1975 - 23/1/09 at 08:52 AM

As you know, fuel out of the overflow in these situations usually indicates blocked jets or other symptoms of varnish induced woe.

You say you blew out the jets - did you check the float mechanism itself? On my TY, the float valve tends to bind up and is a common replacement item for bikes that have been sitting a long time. If it sticks, the float bowls overfill and (esp. if you have a simple overflow vent rather than a drain screw in the base of the bowl) causes fuel to wee everywhere.

I would suggest pulling the carbs apart and replacing all the jets, gaskets and the
float valve. Apparently if you take the metal parts to a good garden centre, they have bath type cleaners for lawnmower carbs that are the business.

Running problems may also be caused by an air leak - don't know if it runs an airbox or sock filters, but if it's a particularly old bike and you haven't done this before, I'd replace the carb and airbox rubbers, as they've probably hardened and shrunk and will leak air.

Is your garage damp? Have you checked you have good spark? I know you replaced the battery, but you might want to check the rest of the ignition.

Don't disagree with you on the emulsion tubes. It's unlikely to be them, IMHO.

quote:
Originally posted by NigeEss
Decided to get my bike going again, a Kwaka ZX550A4 that's been hidden under a pile
of sh... in the garage for over a year now. Fresh fuel, new battery and it fired but rough
as a bears arse and fuel leaking out of the carb over flow.
Stripped the carbs and cleaned them up, blew the jets etc but on reassembly I noticed the
emulsion tubes are not all the same. Two have four holes at the bottom and ten at the
top the other two have six at the bottom and four on top. Jets and needles all the same.

Obviously one pair will be for cylinders 1 & 4, other pair 2 & 3 and is probably to do
with cylinder temperatures. I'm thinking the ones with less holes at the top ( exposed
on wide throttle ) will give richer mixture and hence cooler for cyls 2 & 3.

Or I am I misunderstood emulsion tube function ? That is to atomise fuel with the correct amount of air.

Haynes was no help as were the guys at at Kawasaki centre.



[Edited on 22/1/09 by NigeEss]