I need to reset the float levels in my carbys to stop the overflow on my 1974 Z1A Kawasaki

doubt it

Float height should not be overly critical.. Why was the float level changed just to rejet? gas overflowing sounds like a stuck Float.

if it has carbie/s then check for a faulty float needle and seat
may be a simple thing such as a hair stuck under the needle as it is flooding

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Hi,

the main jet float level needs adjusting, and the needle valve may need replacing. Carefully unscrew the base fron the carby (after turning fuel tap off), then check that the float moves freely up and down, while holding it up turn the fuel back on, and see if the needle valve is stopping the fuel. Slowly lower it to the level position, fuel should come out then. Give the carby a good clean, DON'T use wire, JUST SOLVENT AND AIR.

Thanks,

Adam.

More than likely some grit or build-up is stopping the float bowl needle from stopping the fuel flow through the needle valve seat.

To test and clean, turn off fuel tap and drain fuel from carby via drain plug. Loosen carby manifold clamps and rotate carby enough to undo floatbowl. Return carby to level position and place a spill container underneath carby, turn fuel tap on and off (enough to allow small flow of fuel through open needle seat).

Now, gently hold up floatbowl with enough lift to close off needle valve seat and turn fuel tap on. If fuel still comes out you have a severe needle and seat problem requiring a replacement, if only a small weep of fuel is emitted it may just need a clean with a carby cleaning spray.

If no fuel comes out, your problem is the height adlustment of the floatbowl's level. Your engine is not using all the fuel that can be delivered and flows out the overflow outlet. The floatbowl level should be re-set incrementally to avoid leaning out your engine at high revs with too low a float level. To close off with a lower level you need to bend the small tab upwards.

The link below is for the same carby in exploded view format with all parts named. Cheers!

http://www.cmsnl.com/yamaha-pw80r-2003_model11164/partslist/A-09.html

Float tabs come set flat to surrounding plate, bend up to decrease level and down to raise level. Raised level too much and you risk fuel overflow on sustained inclines and too low a level and you will lean out at high revs and damage valves/piston real quick. There is no set level to speak of, but better to err on the side of losing a bit of overflow. The overflow drains from the carby via a plastic hose from just above float bowl flange.
Cheers.

I would say the problem is in your carbys, with the float levels, or a sticky needle and seat. If you open the fuel valve, fuel will flow into the carbys, ans shut off once the correct level is reached. I think the problem is in your carbys, not the fuel valve. I would remove the carbys, take the bowel off the bottom, and check the needle and seat, and float levels. It is not recomended to change the float levels from standard.

sounds like the float level is set to high and it is laeking out the over flow. try adjusting float level.

I don't know if its any help but I've fixed my Honda with similar problem. It turns out I reassembled the rich carbys air cut off valve incorrectly. Have you checked yours? I'm wondering if the cut off valves somehow affect the other parts of the carbys. Mine is running sweet now.

•A bucket for soapy water •Soap or liquid detergent; automotive cleaners will work •Gloves (to keep your hands clean) •Bug and tar remover •Degreaser and/or engine cleaner •A toothbrush •WD40 •A brush for wheel cleaning •Wheel cleaner •At least two microfiber or 100% cotton sponges •A variety of soft cotton towels and more abrasive rags •A chamois cloth for drying