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Onan 2.5 LK Questions, Manuals, APU Conversion Questions


I received a free (don't know if it works) Onan Generator with the following specs.

Model 2.5LK-1R 6000J
Serial 1071338525
120 V
2.5 KVA
2500 Watts
PF 1.0
Amps 20.8
Rpm 1800
Bat 12

I have the following questions:
Where can I get paint that matches the original Onan green, as I want to restore this unit to new condition?
Does anyone know how, or is it possible to convert this unit to electronic ignition?
I downloaded the master repair manual, and also a 90-0196 repair manual. I'm not sure if that is the correct manual for my unit, but it did list LK models in the manual. I also showed that the LK can be wired for both 110 and 220 Volt, however my generator only says 120 Volt on it. Can this unit still be wired for both 110 and 220 volt, or am I limited to just 110 volt on this particular model.
Please advise if this is the correct manual, and I am also in need of a parts manual for same.
Are parts still available for these units, and who would you recommend for purchasing parts.
I need the air cleaner to carburetor tube. Are these available?

Also, I am thinking of converting this to an APU unit for use on a Semi Tractor, and would like to run an air conditioning compressor off of the unit to supply cold air without idling the truck, and probably an electric heater for heat in the winter. Not sure about the heat solution yet. Anyone have any plans of how this could be done, or has anyone done one of these conversions before.

This site is just awesome. Thanks for the great work and dedication, and thanks in advance to anyone answering this post.

I forgot to ask a question on the original post.

My carburetor had a bunch of flange gaskets sandwiched together between the carburetor and the block. Is the supposed to be some sort of carb spacer in there? It just didn't seem like it was put together properly.

Ed Sparks

In Memory Of
Last Subscription Date
Welcome to the Stak:
Your unit is a 2500 watt 120 volt single phase only, Spec J

Serial number shows it was built in October 1971.
Original Onan rattle cans can be found on E-bay or you can try to have a local automotive paint shop match it up.

Others with more knowledge of the LK will chime in about electronic ignition conversion.
would work as an APU as long as 2500 watts will meet your needs.

Kevin K

Last Subscription Date
In addition to the Onan master Service manual, there are a few other manuals for the LK:

930-0310 Owners manual
930-0501 Service manual
930-0220 parts
930-0221 parts

My LK has both a metal plate and a spacer (approximately 1/4" thick) between the carburetor and engine.

Some parts are still available, others you will have to hunt for. Try onanparts.com, a sponsor here, or searspartsdirect.com.

Max Thompson

Last Subscription Date
Parts & service manuals for your unit will cost 1 e-mail address to send them to.

Maintenance parts (points, plugs, brushes) can still be had though you won't just walk into most Napa stores & get them by asking the counter person. Not much else you should need, baring major failure.

The LK is a great old workhorse.


Thanks all for the quick response. If anyone has any working drawing GS for an APU conversion showing a/c compressor mounting, in cab controls, freon plumbing and valving etc. I sure would appreciate any input.
My email address is Farmington@gmail.com. I am also going to be posting some sterling engine information that I think will just amaze you all. Look for it later this evening.

---------- Post added at 02:17 PM ---------- Previous post was at 02:14 PM ----------

Sorry, I posted the wrong email address. It should have been Farminfr@gmail.com


I kept the original ignition system on mine. I installed new points & condenser & it has been trouble free for a long time.


I have the exact same spec number as you and mine runs on propane? Great little generator, I just bought an extra one for parts but it is a gas model.