83 KZ750K1 fuel petcock question

I finally have my bike together enough to ride but now I have about 2 gallons of fuel on the ground spilling out of the bottom of the airbox. So I have 2 questions:
Is there a fuel cutoff on the petcock? it's kind of rusty and all I can see is PRI, ON and RES.
What do I turn the fuel valve to when it is parked so all of my fuel won't leak out?

And I see a second port on the petcock that I am assuming is the vacuum port but nothing is connected to it.
I just got the carbs back from being cleaned and synced. The mechanic says I might need to tap on them a couple of times to make the floats work at first. I've done that.
Thanks.

Two problems, one the carbs aren't working correctly, two the vacuum line isn't hooked up to the carbs. If the fuel isn't shutting off in the on/off position you have three. In prime it is always on.
Steve

There are 2 vacuum lines that go to each carb near the manifold and then a T connector from these lines that is capped off. This vacuum line looks too small to connect to the petcock but there aren't any other vacuum lines unused.

I think it would be very helpful if you could provide pictures of your carbs and of the ports on the carbs for the "vacuum lines" and any other carb ports. Ed

Edited: From the KZ750-K1 airbox diagram at partzilla. In the Kawasaki clean air system portion of the drawing there are 2 Tees >> the one nearest the airbox cap has the carb vac port tubing & the other Tee underneath the fuel tank has the petcock tubing.


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SWest wrote: Two problems, one the carbs aren't working correctly, two the vacuum line isn't hooked up to the carbs. If the fuel isn't shutting off in the on/off position you have three. In prime it is always on.
Steve

CORRECTION, ON/RES

I am going to put some pictures up but could someone just answer where the fuel switch position is supposed to be when parked overnight, and assuming I have a working petcock? PRI? RES? ON?

ON if the petcock is working properly. In that position fuel should only flow through the petcock when the engine is running in which case vacuum is applied from the carb to the petcock. With the engine shut off the petcock should prevent the flow of fuel. Of course if the petcock diaphragm or other components are damaged fuel may flow even with the engine shut off. Ed

Ok thank you. Here are some pictures of what I have.

If there's tubing connected to each carburetor, then the tubing in the last pic is for the petcock vac port in 2nd pic. In the airbox diagram the carbs would be connected to the tubing nearest the airbox cap & the petcock vac line is connected to the other T underneath the fuel tank.

Partzilla >> OEM >> Kawasaki >> 1983 KZ750-K1
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