Kawasaki z750 abs. Vacuum (pression) in fuel tank

More than likely you have a bad fuel petcock. No fuel should go from tank to carb without the engine running because the fuel is pulled by vacuum. Remove line from petcock an have it set to on or reserve position and if fuel comes out it is bad, and let's the fuel continue to flow to the carb and seep into the engine oil also. Mine was bad and had my oil thin as water with all the gas in it. Wonder it didn't wash a bearing out of the engine. Check and drain oil immediately if the petcock is bad.

Hey Adrian,
This should get you started.. KAWASAKI Z750 ABS Service Manual

Does your bike have a vacuum tap? Sounds like your bike has a vacuum tap. In that case you should unplug your fuel hose, and unplug the hose that goes from the fuel tank to the engine. This hose should be smaller and should be unplugged at the engine side not the gas take side. Apply a vacuum to the hose (suck it), and you should have gas coming out of the main fuel line you disconnected. Make sure you have something to put the fuel in. If you can't suck hard enough (hehe... sorry coun't resist). plug the hose back on the engine and spin the starter a few times til fuel comes out. This may need to be repeated a few times.

Check this out. page 1-9.
Kawasaki zrx 1100 zr 1100 Service manual Download service repair owner...

Also, Fuel system is at section 2.
2-2 has a detail of the carburator.

try this free Kawasaki Z750 service manual model year 1980 to 1988

https://drive.google.com/file/d/1BY6VG3WXmtV0tu7XLprGd4zNyMyaNfvx/view?usp=sharing

Test at idle this has a internal pressure regulator in the tank, the pressure at idle should be 55-62 psi at idle,how did you measure 95psi?The TL is plaqued with loose terminal connection on the crank sensor causing intermittent start up.Did you check that?Coolant temp sensor how about that one?it on top engine next to EGR check that for proper fitting. also proper coolant level.You check the map sensor? no vacuum leaks it has to have go vacuum signal .

Some older bikes (don't know what year yours is) have an engine vacuum line that allows fuel to run once the engine starts. (Starts with the fuel that was already sitting in the carb's) If you put a vacuum hand pump and start to pull vacuum, the fuel will flow...
Otherwise, something may be plugged.

If you're building up vacuum or pressure in the fuel tank, your vent line is pinched or plugged. It is a rubber hose that comes off the fuel tank, usually runs down the right side and discharges vented air out the bottom somewhere.

KAWASAKI Z750 ABS vacuum (pressure) in the gas tank