Wont stay running for more then 20 seconds

tony alexander this sounds more like a fuel delivery issue. So I'd focus on the carburetor i.e. stuck float or needle valve as well as checking the intake and exhaust valves. The ZTS7500 comes with Kohler as well as Briggs and Stratton engines (should be a 44P777-0130-P1 or 44P777-0130). The Intek™ OHV V-twin utilizes a fixed jet, two barrel, side draft, flo-jet carburetor. Except for idle speed, the carburetor is non-adjustable. The carburetor incorporates a fuel shut off solenoid which controls fuel flow to the fuel metering system. The solenoid is controlled by the ignition switch. Try and see if you can give us your engine make and model so we can get more information about the fuel system.

is a typical diagram for a B&S 44P700 engine carburetor #133 shows the float

Before you disassemble anything, try this -- it worked for me.

Buy a can of Seafoam gas treatment (https://seafoamsales.com/small-engines/), put some in an empty gas can, and fill the can with new gas. Drain the gas from your tank. Swish the gas can to mix the seafoam and the gas, and fill the tank with the seafoam/gas mixture. Now start your engine.

After I did this, my lawn mower ran like new. It still is, months later.

The symptoms described is a signature issue on this type Briggs 6.5 Carb (and others that use it)

If any debris gets in the fuel and fits thru the float valve it settles at the high speed jet that is at the bottom of the fuel bowl. In fact it is the brass piece that holds on the fuel bowl to the carb.

I find it best if it comes down to having to fiddle with this jet, to remove the carb, get some Lacquer thinner and a small brush and thin wire and really clean clean clean all dirt off the outside. Then throw that Lacquer thinner away, clean the container and take the hi speed jet screw out of the fuel bowl. If you are careful and gently pull things apart, hopefully you can save the rubber gasket between the bowl and carb. If it sticks, wd40 it with spray and keep working it off.

Next, Ya gotta have some air pressure to blow out the carb, and you first should let it soak for a while. Take the float off and shake it to make sure there is no fuel in it. If it is leaking and I have never found a plastic float that leaks, it will have to be replaced.

Once the carb has soaked, wire out all the holes and then soak again and wire again, and then blow out every hole you see. Make sure to put the air tight against the float valve hole.

Reassemble, the reverse of taking it apart, reinstall, and next, Clean the filter with air and clean the filter holder with the left over carb Lacquer thinner, so that you are starting out clean.

And don't take any short cuts trying to prime and start the engine without reassembling everything. All the parts including the filter are required to be installed to get the silly thing to run.

Prime it with the prime bulb and pull away!

There is another possibility that hasn’t been mentioned- water in the bottom of the fuel tankf. If just the right amount of water gets into the tank, it will allow a mixture of fuel and water to get into the carburetor. And you get the same symptoms. After trying several times to start the engine *some* fuel will make it into the engine from all the shaking as you pull the starter cord. It can be enough to start, and run for a few seconds before more water is pulled into the carburetor and the engine stalls again.

Solution- disconnect the fuel line from the carburetor and let the fuel drain into a clear container. You will see the water in its own layer at the bottom of the container. Don’t forget to drain the fuel bowl on the carburetor also.