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Can I turn a petrol engine into a water pump? Answered

I may be able to get my hands on an old 2 stroke engine. The spark plug threads have gone completly and mainly going for spares.

I was wondering if sealing the spark plug hole, fit an electric motor to the drive shaft then separate hoses to the fuel inlet and exhaust could it then pump water or is this another of my hair-brained ideas?



1 year ago

Bugger, I was right, its another of my hair-brained ideas. I'll just add it to the long list of failed ideas. I've no need for a compressor.

Now what other stupid ideas can i think of.....

Thank you everyone. =)


1 year ago

A waste of an electric motor.. And you might loose a finger tip this time ;)

It will pump water but with time it will trash the crank shaft, barrings, valves, and rings.

Two strokes engines use oil in the gas to lube the crank shaft, barrings, valves, and rings.

Most two stroke engines suck air in through the carburetor past one way valves into the crank case on the compression stroke. On the power stroke it compresses the air in the crank case until the piston passes the exhaust ports exhausting the spent fumes then the piston passes the intake ports letting the compressed air in the crank case into the cylinder starting the process over again with the compression stroke.

To convert a two stroke engine to a pump you would need to seal the intake and exhaust ports at the cylinder, fill the crank case part way with oil and put two one way valves at the spark plug port. One, one way valve to let water in the cylinder and one, one way valve to let water out of the cylinder. However this won't keep the piston rings or the steel cylinder liner from messing up.

This makes a better air compressor than a water pump.

+1 on the air compressor. That is one of the primary thing that the piston engine does to start with. If you look at water pump designs they don't use pistons they use vanes to push the water in some way. It is much more efficient and can create pressure with the water.

I guess your more likely to get more water out of the spark plug hole! arrange a one way valve on the inlet pipe.

HOWEVER a 2 stroke engine relies on the oil content of the fuel for it's lubrication. Without that it isn't going to work for long.

You probably could move some water with it but engines are intended to work the opposite way: a fluid does work on the driveshaft, not the other way around. It won't be very efficient you could probably just buy a cheap water pump for a similar price as it would cost to retrofit your engine. Just go to a junk yard and rip one out for probably <$10.

Look at some pictures of the two stroke cycle and work it out. Water is very viscous. How will it flow through the engine ?