DIY efficient gas generator with a 4 stroke engine.

Home Made Generator

I made a DIY Inverter Generator with a 4 stroke Subaru robin EH035 engine.

DIY Inverter generator

I started with a powerful 4 stroke 1.6HP engine.

Its quiet, efficient, less pollution, and you don’t mix gas and oil.

The engine has been sitting a few years, so I did an oil change.

Here is the alternator I used to make my generator

I used my RPM meter (Amazon) (It uses a laser and reflective tape to measure speed) to measure the engine output rpm.

Here is an example from my cars pulley.

I also measured the engines RPM from the flywheel.

Here is my original design. I did not know which way the alternator needed to spin…

I needed a way to attach the gear to the alternator. I used magnets…

Then I welded inside the gear to hold it to the alternator.

It looks good to me.

Now I needed a frame to hold everything

I used a piece of metal across with my magnets to hold everything square as I welded

Now I needed to make an Engine mount.

I needed a second point for the engine to mount to. Here is what I made

Now to mount the alternator in the spot I originally wanted it.

Nice and compact. I like it!


Well, it turns out the alternator has to spin the other way to generate power… boo!

Now I must extend the platform to support everything in the new configuration.

Now to finally test the thing…

Alternators need 12v to power them on to generate power that’s why I have the battery.
I added a switch and LED to the alternator to turn it on/off at the right engine RPM.

Here is a wiring Diagram I made showing the Honda/Acura OBD1 pin-out and wiring I used.

The alternator did not function… so I had to open it.

The brushes on the alternator were bad. The new one is on the right.

Time for another test… and it works! yay!