On my 04 Jinma, the only way the engine stops is by cutting off the fuel. Normally, the only way to do this is the shutoff knob. But if you are not diligent about only using clean fuel then the numerous fine screens in the fuel line can clog up very quickly. I think that my Jinma had one in the tank, one at the bowl, and there was a third that I can not remember where. A few years ago, I removed the tank and bowl screens because they were such a pain to get to and installed an inline filter between the tank and bowl. This filter can be changed in just a couple of minutes with little more than pliers. Find the third screen and just clean it.
I think that if you had a problem with the head or gasket you would have much more severe symptoms than a slight rise in temp. You would probably get exhaust in your cooling system that would cause boil overs, or might see antifreeze in your oil. Check the oil and antifreeze levels, but don't panic if the are just a little off. My Jinma will reach close to 100 when I am working it hard. Thermostats can go bad and is an easy replacement for under $10 from NAPA. I would start there. My original thermostat broke at the arch that the expanding pellet pushes against. Overall, my Jinma is a darn hard working machine that takes a licking and keeps on ticking.
