1992 KZ1000P Fuel Tap (petcock) Woes...

Fuel Tap spits gas out of diaphram block notch when the bike is running and also I'm pretty sure a little gas is getting into the crank case when the bike is running. Gas does not come out of the outlet nozzle when the bike is off.
Diaphram *looks* good, block looks good, o-ring and everything else*look* good and there doesn't *seem* to be any vacuum leaks. Oh and I did stretch the shix out of the spring to put more preasure behind the o-ring plunger.
Any of you guys ever have this problem? If so what was your fix?

Also I have never heard Anyone talk about the very small phaneloc stopper in the vacuum intake nozzle of the fuel tap. Can't blow *in* but Can suck *out*.

Anyway, any and all ideas/solutions are Greatly Appreciated!

Adios, Kip

I think the only way fuel can leak out of the petcock is when one or more of the seals needs to be replaced. Stretching the spring will make it more difficult for the valve to open. Both Kawasaki and K&L make good replacement parts.

So you are recommending rebuilding the fuel tap? This will be the 3rd time I've rebuilt in 5 years.
Anybody else have Any ideas?

Adios, Kip

Can you tell me more about this phenolic part? Got any pictures?

Anyway, all of the times I've rebuilt these petcocks the old parts *looked* fine. I think you must have a hole in your diaphragm to have gas coming out of that notch though. It's a very flimsy/finicky mechanism. New rubber seems to be the only cure. You can get the rebuild kits for as low as $13 these days. Oh, and remember that the notched side of the plate is supposed to face the outside of the bike.

The thing I hate most about the design is that gas ends up in the crankcase. How stupid is that? Maybe in Japan they always park motorcycles facing uphill...

Probably time to pull your carbs and polish those float valve seats, maybe replace the needles, and set the float heights. It is possible to find Viton tipped replacement needles that might seal better (haven't tried this myself yet, but may the next time I need new needles)

Some people are convinced that adding a restriction to the vacuum line can extend the life of the petcock diaphragm. I'm more inclined to believe it is the ethanol in the fuel these days that destroys them.

I don't understand why you've needed to rebuild the petcock so often. My ZRX is 15 years old and I've rebuilt its petcock twice, and once was my fault. Before that, I put more than 60,000 miles on a Concours, and rebuilt its petcock once.

On my fuel tap the brass vacuum inlet nipple can be unscrewed. In between the fuel tap body and where the vacuum nipple screws into is the piece. It *seems to *float* only allowing vacuum to *open* it. If you blow into the vacuum nipple lt closes.

Gosh I don't want to have to take the carbs off Again. that would be a third time in two weeks and they are a REAL pain to take off and put on. But what you are telling me about the floats and shut off needle makes sense. Damn I knew I should off checked float height the first TWO times I had them apart!

I'll rebuild the fuel tap Again with New parts and see where that gets me and then maybe (most probably) remove carbs AGAIN.

I think I'm going to take a break though getting a little behind on other things.

Oh yeah and the *notch* on the diaphram block is on the o-ring plunger side, at least that's my take on what the manual says. And thinking a little more does it matter what position the *notch* is at, left, right, up or down?

Thank A Lot, Kip

Maybe my floats are off or I need to work on the gas plunger needles and I had previously missed diagnosed. Maybe I have Two problems that need attention, the carbs And the fuel tap.

Adios, Kip

jackleberry wrote: Anyway, all of the times I've rebuilt these petcocks the old parts *looked* fine. I think you must have a hole in your diaphragm to have gas coming out of that notch though. It's a very flimsy/finicky mechanism. New rubber seems to be the only cure.

Just went thru this on my KZP. Bought a brand new diaphragm from Partzilla ($10) and it was pouring fuel out of that notch. Took it apart and put it back together again few times with the same result. Took a closer look at the diaphragm and it had a very small tear in it very close to the metal. This was a brand new part, mind you. Replaced it with another and no more leaks. As the poster above says the only way for them to leak like that is with a broken diaphragm.

I suggest trying to verify 1 problem at a time, starting with the fuel tap. I have never done this, but you could test/simulate the operation of the fuel tap off the tank and verify that it doesn't leak. Could even add small amount of air pressure to make sure.

The other thing I have seen people do is install the diaphragm kits incorrectly, the FSM sometimes isn't clear enough to spell out how all the layers and tabs and holes align. take it apart and really examine what's going on in there.

For any nipple type leaks, a liquid weld product will seal it. I've also used tread to make a very tiny o-ring type gasket (successful but i don't recommend the method).

old one is torn and looking beat up


the gang of parts


o-ring on nipple (broken in photo)


alignment of critical air hole and tabs

Hey great pictures Amigo, Thanks!
When you reassembled did you have the *Notch* pointed on the vacuum inlet nozzle /nipple side?
The reason I ask is the main fuel tap/petcock body does have different patterns on the vacuum side.

And yeah tackle One problem at a time but carburetor removal is haunting me!



Adios, Kip

Probably time to pull your carbs and polish those float valve seats, maybe replace the needles, and set the float heights. It is possible to find Viton tipped replacement needles that might seal better (haven't tried this myself yet, but may the next time I need new needles)

How would you recommend "polish"ing the float valve seats?
Also you wouldn't happen to have a source where to buy Viton tipped needles that would fit my bike would you?

TIA, Kip

hardworkinpd wrote:

Probably time to pull your carbs and polish those float valve seats, maybe replace the needles, and set the float heights. It is possible to find Viton tipped replacement needles that might seal better (haven't tried this myself yet, but may the next time I need new needles)

How would you recommend "polish"ing the float valve seats?
Also you wouldn't happen to have a source where to buy Viton tipped needles that would fit my bike would you?
The
TIA, Kip

I use some Mother's polish on a q tip. Put the seat in a cordless drill and work it over with the qtip until the inside has a mirror finish. Clean thoroughly before reinstalling. Use a new o-ring and grease it a bit so it doesn't get cut when you press the seat back into the carb body.

Here's a link to the needles:

www.mikesxs.net/product/48-5014.html