In fact, the O-290-D2 pistons and cylinders are interchangeable with the O-290-D pistons, although the D2s are a higher compression ratio. While the -D2 model case has hydraulic lifters and the -D has solid lifters, if one uses the D2 pistons in a D model the output is close to the same, although the cam profiles are slightly different. However, the pistons, ring sets and especially cylinders are getting scarce; for either model. Most other parts are interchangeable with other lycomings, so aren't quite so problematic. The O-290 series engines have been out of production for over 50 years and Lycoming (and after market companies) stopped making parts for these engines decades ago. The parts inventories are drying up to where these engines are getting as difficult to support as a Franklin. Cylinders can almost always be overhauled, so if you can find one, you usually have to have one to exchange as a core.
The same problem exists, although not quite to the same extent yet, with the old O-235-C model engines. Cylinders are getting to be difficult to find. The later O-235-L series engines have parts readily available and in production (as does the new O-233, which is the same core engine), but even though the cylinder bores are the same, the studs are a different size, so the cylinders are not interchangeable without re-studding the O-235-C case to match the newer L series case. ? Jeff Scott Los Alamos, NM Sent:?Saturday, January 16, 2016 at 3:28 PM From:?"brian.kraut--- via KRnet" <krnet at list.krnet.org> To:?KRnet <krnet at list.krnet.org> Cc:?brian.kraut at eamanufacturing.com Subject:?Re: KR> Piston rings I had an O-290D in my Pacer and had a hard time finding parts when I needed to do a top overhaul. Pistons were pretty scarce. I did find what I needed from Gibson. http://www.gibsonaviationok.com/ The O-290D2 is easier to find parts for and for future reference if anyone is looking at planes with the 290 try to get a D2 instead of the D. Parts are easier to find, I think a bit more HP, and it has hydraulic lifters unlike the D. I called a Lycoming rep at the time when I was trying to find pistons and he told me that the reason the 290D parts were hard to find was because it used most of the same parts as the 290G ground power unit and a lot of the 290D engines were now in experimentals and using the 290G parts, so much so, that people were not buying many 290D parts anymore hence they stopped making them. Cc: BOB ROBERT This is a shot in the dark I am in need of piston rings for a 4 ring 0290 Lycoming Also engine mount rubber bushings _______________________________________________ Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search[http://tugantek.com/archmailv2-kr/search]. To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org please see other KRnet info at http://www.krnet.org/info.html[http://www.krnet.org/info.html] see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org[http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org] to change options _______________________________________________ Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search[http://tugantek.com/archmailv2-kr/search]. To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org please see other KRnet info at http://www.krnet.org/info.html[http://www.krnet.org/info.html] see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org[http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org] to change options _______________________________________________ Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search[http://tugantek.com/archmailv2-kr/search]. To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org please see other KRnet info at http://www.krnet.org/info.html[http://www.krnet.org/info.html] see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org[http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org] to change options
