KZ440 LTD 1982 Carbs

Hey people

So my KZ440 LTD 1982 was running like it had dirty carbs/clogged jets...Would run fine for about 10 minutes and sputter out until it died. I got to the carbs and found they are perfect. Is it possible this is just a petcock issue? Perhaps the vacuum is not working? If not how do I test that?

What is the best thing to do at this point? I have read from a few sources to just run the bike on prime and shut it off to on when parked?

hayyylp (Also worth mentioning I am doing this for the first time and learning as I go)

thanks!

If it runs properly on PRI, then the petcock needs attention.
If you have a paper fuel filter, it could be restricting flow. Replace it with a proper one.
The fuel cap vent may be clogged. With the tank half full or less, open the cap and take a ride. If it works ok, the vent needs to be cleaned.
Might be a bad coil. When old, they can malfunction when hot.
Might be severely out of spec valve clearances. If some are near zero when cool, they can go to less than zero when hot, causing similar symptoms.
If you have a vacuum operated petcock, you cannot turn it off.

I guess my main question is, what should I check while the tank and carbs are apart? I found it strange the petcock leaked gas when set to prime, but did not when it was set to on (when I removed the gas tank)? Most likely due to me not knowing anything...

That's a symptom of a bad petcock. I was thinking coils but check that first.
Steve

How could I test the petcock? I have it off now... Is it just worth buying a new one? As far as the stator, I already bought a new one but am having a hell of trouble getting the old one off, the side cover has somehow made the belt cover impossible to get one hex screw off. See photo 2.

Testing the current stator now...I've had history with dead batteries...

Since you have the petcock apart, it would be silly not to clean it and replace all the rubber bits.

If you can get genuine Kawasaki parts for it, they are well worth the extra cost.

what is malfunctioning with the petcock you think? clogged fuel line? It didn't seem to ever leak gas...

Any thoughts on getting a non vacuum petcock as seen in pic?

Ouch! Don't you just hate when you discover that the PO was probably not too smart. At least on KZombie, the fastener problems have all been - absent ones. That hex bolt jammed into that side cover relief looks like a real challenge... I'm guessing the socket won't slip over the bolt head due to the case edge. Hmmm? May have to resort to a open-end wrench and turn that thing 1/16 at a time from below the frame until it clears the case enough to fit a socket on. My fingers are crossed for you that it's a shorter than should be bolt so you're not on it for hours.
Wish I could help with the petcock issues but I haven't had to deal with it... yet... Did you follow the procedures listed in other threads here already and determine it is in fact the problem? Seems pretty straight forward to test but in the other thread at least, the unit didn't have to be removed from the tank to confirm it's functioning properly.

Ah! Here it is... You kinda' have to interpret the young man's english. Anyway [ Response to Petcock Testing Procedure in manual ]

Ya the hex bolt is killing me, I tried getting it off for an hour yesterday before being defeated. I have it loosened, but is still a snails pace. I'm still having trouble getting the stator off. Also the wiring is a bit of a mess and I am reluctant to cut everything open. Would love to ride with this amazing weather!

Considering just buying another bike that works and building this guy from scratch to learn about bikes.

prizethedoubt wrote: I found it strange the petcock leaked gas when set to prime, but did not when it was set to on (when I removed the gas tank)? Most likely due to me not knowing anything...

Did you mean leaking out of the petcock, or fuel was coming out of the fuel line? When it is set to PRI, fuel is supposed to run freely out of the fuel line. This position is used to fill the carburetors when the have been off the bike or otherwise drained. Both ON and RES require engine vacuum to allow fuel to flow.

Whether or not it was malfunctioning, I am not a fan of reusing old rubber bits, especially if I am not 100% sure of their age and reliability. For me, replacing them at this point would be an easy way to certainly eliminate a potential problem.

prizethedoubt wrote: Hey people

Would run fine for about 10 minutes and sputter out until it died. Is it possible this is just a petcock issue?
Yes.

Perhaps the vacuum is not working? If not how do I test that?
Possibly. Turn the petcock to PRI and ride. If the symptoms go away, then you have identified the source of the problem. If they return, you have likely eliminated a suspect.
You can also use something like a Mityvac to pull vacuum on the petcock to test it. Remove the fuel line at the carbs, point the line at a suitable container. With the petcock set to ON or RES, make vacuum (The Mityvac should be hooked up to the vacuum fitting on the petcock.). If fuel lows freely, it is probably ok. If not, it needs rebuilding. A tiny pin hole in the diaphragm can fool you here, so a careful visual inspection may be the most reliable way to know.

What is the best thing to do at this point? I have read from a few sources to just run the bike on prime and shut it off to on when parked?
If you have a vacuum petcock, there is no OFF position. Disassemble the petcock, clean it very carefully, replace all the rubber bits with new ones.

hayyylp (Also worth mentioning I am doing this for the first time and learning as I go)

thanks!