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Engines To Sell as Parts, or To sell Assembled and Pickled?

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Dave Baxter

Well-Known Member
Lifetime Supporter
Nov 14, 2007
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Or not to sell at all in this crazy world. O-290s are not all that desirable these day, should I just keep them, or sell them? I like many have acquired these engines and parts over a period of time, and it did not start out this way? Please read my previous post regarding engine overhaul Follies for more detail as to how I became the owner of three O-290 engines...

https://www.biplaneforum.com/thread...n-the-lycoming-o-290-d-o290-d2-engines.19015/ Post #1

I have two engines, actually three if you count the one in my SA-100. All are O-290s, and these two are the ones I am talking about doing something with. One is a D, and the other is a converted GPU. The third and current engine is in my SA-100. Is the O-290-D2 with .010 low compression cylinders and after changing the #1 cylinder several months ago and now with 25 hrs of flight time appears to be working just fine, as most all of it is new. Especially the bottom end, with all of the latest and greatest parts and service bulletins like the oil pump gears and the adjustable oil pressure relief valve. So at my age I think it will probably last me for the rest of my flying life?

So why should I keep the other two engines, I suppose one engine just in case might be in order, and if so which one would that be?

Engine #1
Is an O-290-D solid lifter certified engine with log books. The case has been overhauled by Ly-Con with an 8130 yellow tag. The case has been drilled for oiling the idler gears. It has the latest oil pump gears and accessory housing for a fuel pump along with the idler gears, it also has the adapter for a remote oil cooler that bolts onto the accessory housing, It has new bearings and a STD-D shaft, and has 3/8" propeller mounting lugs. Three of the cylinders have approximately 300 hrs and are chrome, and have been honed with the valves lapped, the other cylinder is from Gibson is fresh chrome, with new rings and piston and has never been run, it also has new rod bolts. It has either the MA4-SPA float Carb, or the PS-5C pressure carb to pick from. The pan is the one for these larger Carbs, It has the latest new cam# SL75706 and the hard black diamond face solid lifters #15B28739, There is also a new gasket set, and most of the hardware has been replated and has the light 149 tooth starter, there is no alternator, but it does have the three hole mounting bracket the alternator mounts on, which is my understanding not easy to come by. There are probably several things I have missed. But you get the picture.

Engine #2
Is the O-290-G A converted GPU (Ground Power Unit) These engines were quite common back in the early days to power home built airplanes. I was looking for O-290 cylinders when I came across this engine, and after looking at the case and all of the other parts could not get my money out fast enough to buy it! The Case has some of the nicest machine work I had ever seen as most of he early GPU case conversions left a lot to be desired. My engine guy who is also a machinist checked all of the dimension's as well as drilled it for oiling the idler gears, with the mod for the adjustable oil pressure valve. It has new oil pump gears, and the accessory housing for the fuel pump, as well as the idler gear cam to operate the pump, It has a GPU shaft that has been plugged and plated, along with the reinforcing flanges a common upgrade for the light GPU flange and the oversize 3/8"propeller bushings required for the GPU shafts. It has four cylinders freshly honed with thew valves and ready to go from Premier Engines, it has four new pistons and rings, and also will be If I decide to sell offered with either one or the other float or PS-5C carb The oil pan is also for the larger carbs and has new O-290 intake pipes, it also has like the other engine the latest new cam and hard black diamond face solid lifters, It also has all of the hardware, but none is plated. There is a gasket set for this engine as well, but it is new old stock. There is no alternator but I think it has the three hole mounting for one, may be for a generator? It has a light 122 teeth starter or the original direct drive Delco/Prestolight, and again I have probably left something out?

I have Bendix S4LN magnetos for both engines, and will sell one set with either engine, but want to keep one set not only for my SA-100, but they will also work on my O-360 powered Starduster Too

I can post pictures in the parts for Sale Section If I decide to sell either engine, and with all of the parts laid out, it has been my experience when buying engines, "Please Read My Post one Engine Follies" That no matter if it is low time, or rebuilt by a reputable engine rebuilder buying one that is altogether even from a trusted friend can still be a 50/50 chance it will run to TBO! That's why I preach if one is to buy an engine its a much better to buy it all apart so one can see all of the parts and that they are indeed serviceable.

This is the reason I am asking, as the O-290s although are very good engines they are old engines and have issues that are becoming more difficult finding serviceable parts. I am leaning towards putting both engines together, an pickling them, so that all of the parts for each engine will be in one place. I am not an A&P, but can get them both signed off by one, if that is an issue.. I have a bunch of money in both engines, but have no illusions of getting it back, I am not even sure what they would be worth in today's market or if someone even wants to buy either of them? And that is my dilemma? Dave

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