coil problem?

hey everyone,

so the bike is a 1979 kz650 B (4 cylinder). it was running perfectly fine until i took it apart now it's running very oddly. when it first turns on it runs fine, then it heats up and it still runs alright, then i take it out for a spin and it starts to sputter through the #2 carb (gas starts to come out through the intake side). from a stop it sputters a lot more until it gets to just above 3k or so rpm and then it runs just fine. if i leave it it'll sputter until it turns off. i replaced the points, condensers and spark plugs and after that still didn't fix it the plugs for 2 and 3 are carbon fouled.

does this mean that it's most likely the coil that runs 2 and 3 that could be bad? when i first assembled it that same coil got really really hot, too hot to touch. could it have overheated and gone bad?

thanks in advance for all the help guys, i appreciate it.

Sounds like you have a bad float valve in the #2 carb.

"it was running perfectly fine until i took it apart"

Sorry, but I gotta ask - why did you take apart a bike that was running perfectly?

otakar wrote:

Sounds like you have a bad float valve in the #2 carb.

Ditto

Does this float valve need to be replaced? I took the carbs apart and noticed that the float was much lower than all the rest and bent the little metal tab to raise it to the same level as the others but the same problem persists.

Oh, and I took it apart because I wanted to hardtail it and now my life sucks....

Thanks again for the help!

It is the little valve that the float compresses, not the float. You may have done more damage by messing with the float. Pull that valve that the float preses on and replace it. I would replace all four, myself. If one went bad than the other three are not far behind. Once you have replaced them than and only than adjust the floats to be the same.

so i got my replacement on, only with two though because that's all they had. but the problem still persist in the same carb. so if it's not the valve, what else could it be? i checked the float to make sure it hadn't lost its buoyancy and it hasn't. i'm completely stumped and pretty frustrated

You need to check the fuel levels in the bowls with a clear tube to see if the float/valve are working. The levels may also need adjusting.

dastardize, this is the Fuel Service Level adjustment that you will be adjusting.



If your are rich or leaking gas out of the overflow then you are running rich. You want to be running in the correct level range or the Green area in this diagram.

IMHO, you will want to use the clear plastic tube method to get the Fuel Service Level in spec. Avoid using the float height method because although it is accurate (i.e. repeatable) it is far less precise (i.e. closeness to the desired spec).

Best of success.
Bill

... and here is a diagram of the Clear Plastic Tube method for measuring the Fuel Service Level.



Best of success.
Bill

Will this also work for the KZ1000?

Oberkfell,

If you are referring to the Fuel Service Level, I don't know since I have a KZ650-B1 and have never owned or worked on a KZ1000 like yours.

IMHO, if you consult your manual or members here who have done this before, I strongly suspect that the procedure is very similar.

Best of success.
Bill

Just a request here... could you add your year, model and location to your signature to get the very best responses... and yes, it is considered real friendly too.
Bill