Generator prime mover


I work in fits and starts, and I have been working on engines rather than gasifiers lately
The other day I was looking at a natural gas powered generator that needed repairs.
Too many repairs for me to justify ,but the generator end was still good.
An old exciter cranked unit from the 60s ( this means unlike a machine with an independent starter the generator itself provide the torque for starting )
Rather than scarp or part it out I am going to try something.

I am going to try and re-power with a more modern OHV design.
Scavenging parts for a GX240 build with higher compression to drive the 3kw head.
This should give me 120% shaft power on gasoline and I am not sure what it will do on NG or propane.

This might have a producer gas application so Im posting my as I go what works and doesn’t


Pictures, please Mr Wallace.
Steve unruh


Sad looking thing aint it?
Picking it up in the morning.

For some reason the picture do not work when posted but I can see them in preview
These are the same image only smaller.
3kw 3600 rpm unit with an NG derated 8 hp K181.

replacement photo added 12/19/2018

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No pictures today.
I started into the plant last night and found rust in the carb, rust in the intake port, broken bolts in the generator end bell ( someone before me tried to take this apart and had a lot of trouble ).
Everything is siezed.
Some of the wiring is wrong electric choke wiring for example and the ignition is not connected to the controller.
Everything electrically seems intact and like most Kohler controllers of this age so its not too hard to work at.

I filed the engine top end with transmission fluid and might in the future try to rebuild this block.
Next I will have to pull the generator frame and pole shoes off and get ready to try and separate the tapper on the generator >> crank shaft.

I am looking for a 1 inch pump crank shaft for a Honda GX240 or GX270, fall back plan is to machine this down to 7/8 taper if a Honda taper is different.
My feeling based on information posted by Honda is they use or offer the same SAE taper most commonly found on generator heads of this type but nothing is for sure yet

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Hey Mr Wallace, your google-linked pictures do load fine.
Maybe, maybe . . . keep the old Kohler gen-side engine wall and part crank for support . . . then separate engine belt drive that.
Alternative fuels and even just gasoline/diesel fuels stretching I do like to operate at lower than 3600 RPM’s. 2200-2600 loaded engine RPM.
tree-farmer Steve unruh


I walked away from a 34 cubic inch 1800 rpm set this week powered by a big flat head.
That would have been a good simple engine for conversion but I am not interested in that right now.

I am building a high speed standby unit with a high compression engine.
have a real hard time finding just what I want.

This dam 34 cube sack of hammers is like an albatross around my neck.
If I do not buy it, the breakers get it.
It’s sitting in the rain as I type this.
I am not willing to sit on this thing for long but I will buy it for 40 bucks and take it home until I can find someone that wants this thing. ( oil and preserve it for now )

Think hard before you ask me to ship it anyplace because its 300 pounds of iron I Intend to break up myself and resell components too unless a local pick can be arranged.

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Good Morning Wallace, If you are trying to sell this presented on the DOW, you might ask AdminChris to transfer your topic to the For Sale section.

And now today your picture links will NOT load up for viewing.

No not trying to sell it, but often I get asked about this stuff.
It made the trek home today, sitting in my driveway right now.
Took three men to unload it.

No its not for sale, but if its broken up I will post details on what parts are available to salvage.
I have to make room in the shop and see exactly what I got myself into

This is not me or my video but it is almost identical.

Work on the high speed unit is slow but I got a lead on Honda engine, found some cranks that might work, and found some speed parts that will boost the compression up to 10:1.
I am going to have to get creative removing the armature, its not responding to the normal tap and pop method with a dead blow so I will have work on it.


Puttering away on the electrics at much much slower pace that I expected.
I still don’t have an engine to work with.


A couple of other photos of plants in the pipeline.
I got to quit bringing stuff home.

I really fell in love with this little unit.
Its a gasoline unit and its a fully functional standby unit I keep just to have around instead of firing up my much thirstier twin Onan.

This is the latest acquisition

and a long term project at this point.



If you look very closely at the coils for the magnetic poles you will see black spots.
This is very bad!!!
Mold I suspect, I do not have the proper test equipment to determine if biologic activity has done any significant damage to this 60 year old machine.

Also my wife is not pleased at all with me that this stuff is inside of her house in basement.
This is right near the TV where she can see.
But it is too cold for paint to properly cure at sub zero temperatures.
I also do not like having VOCs in the basement air but I have an air exchange system in my home and so far I smell no fresh paint in the house.


After stripping and testing and painting Final assembly has begun.
But I still do not have the special high compression engine I want.

Added later.
Going to add some pictures soon.
A problem cropped up with some broken bolts.
Might have an engine next week.


This is all I get when I click on the entries. Pepe


I am not sure why.
Anyone else have trouble?

Me too, three, four, twenty charters. TomC

I just copied and pasted the link into Google search and got error msg.

Does this picture work?
re posting previous photo.
These are uploads and not links.


I could see that pic before. Weird.

Well here is another one.
Everything is clean and shiny and just about ready for the prime mover.
I have some pesky broken bolts to deal with before I start to build an engine and put this stuff together.

My paint is going to stick better than Kohler’s did because everything has been bead blasted and primed with 1201 glyptal.
Everything passes all electrical resistance tests and all wires and connections have been cleaned and tested.