Natural gas perhaps but not water!

If you take a 1 quart canning jar.
Fill it with water.
Put three holes in the lid center.
1 hole on left side, 1 hole on right side and 1 hole in center.
take a copper rod and stick it into the jar on the outer holes being careful to insulate the rod from the lid and seal around the rod with caulk.
Fit a plastic tube to the center whole and seal also.
Attach a 12 volt battery to the two rods. The water will begin to bubble. take the other end of the tube and connect it to the mouth of you generator carbureator or fuel injector.
Start the generator and shut off the fuel supply.
Both diesel and Gas engines will run on the Hydrogen being pulled out of the water in the jar.
If water is problem you can also run that generator on gas from a wood gasifier.
Hydrogen is what deep divers use to weld ships under water. water=H2O

My brother ran a hydrogen rig on his truck about 6 months he got rid of it. You have to use stainless steel hardware, distilled water, baking soda. To much baking soda the mix is to hot not enough baking soda not hot enough. The tech is just not worth the hassle. IMO.

Thus we don't have more.
However if you can get your hands on or build a device to raise that 12VDC steady on to about 100 volts pulse the output will run on tap water, swamp water (after filtering through some cheese cloth and sand, or even manmade water.
These plans are also available on the internet. Some free and some for cash. Either way it will keep the lights on and the ford chugging, if not zooming, down the road.
The plans I saw put it all in a 4" Black PVC pipe. They use two stainless steel pipes one about .53" smaller than the other for the plates. Mount them insulated inside each other. This gives you more plate surface. Then by using a simple high voltage multivibrator (switches the voltage as it is amplified) circuit mounted under the dash.
Guy in town back two years ago when the gas was very high used a stainless steel pressure cooker with two simple electrodes to run his dump truck.
Not neat, but better than walking.

Sorry this took so long had to go through my notebooks. This is the best place to start. www.water4gas.com

As a scientist and son of an engineer, I question the engine.

Knowing what I know about sciencist and skepticism, I find the concept very interesting. Perpetual motion machines be damned, if the energy is stored in a water molecule and one can break the water molecule into O2 and H, and burn the H maybe energy can be harvested.

Sadly, the designer died and no one knows how to build his electronics.