Q: I have a unknown four-cylinder Lycoming that only has these numbers on the case: 2299-24 and 61863 assem. Any help would be greatly appreciated.
A: Jerry, when you said you had an unknown engine, you weren’t kidding! I had to really dig deep in my old Lycoming files before I found what I was looking for.
It may not come as a surprise to you, but what I found certainly didn’t offer much information. As a matter of fact, the only thing I found was the specific engine model that Lycoming assigned to it at the time of manufacture.
The specific model designation for this engine is an O-290-G1B, which I determined by the serial number suffix of -24 and I thank you for providing that.
All of the O-290-G series Lycoming engines were developed for use in ground power units for primarily military aircraft. These engines were never meant to be used for aircraft applications and were never certified to do so.
There have been, however, a few of these converted in the field for experimental aircraft applications, but information regarding what was actually required to make the engine conversions is rather sparse.
I’m going to step out on a limb here and give you my opinion for what it’s worth.
I’d forget about doing anything with this engine for aircraft use for a couple of reasons. The first would be the cost to convert, and the second is the hard fact that I wouldn’t be able to tell you where to begin to look for any parts for this engine, which could mean the money invested to do the conversion would be a total waste if you needed a certain part that was no longer available.
I apologize for throwing a wet blanket on your fire to have a viable engine for your project, but from listening to horror stories from people who have been through this in the past at Oshkosh and SUN ‘n FUN over the years, I just am not in a position to encourage you to go forward with this engine.