Ok, I have found this for sale: YS120 supercharged 4-stroke with 3-blade prop, aluminum spinner and smoke muffler. Was purchased for use with Carl Goldberg Ultimate Bipe. Engine had a couple tanks of fuel ran through it for break-in about 10 years back but never got cleaned out after running, so it's a bit gummed up. Should be good as new with a thorough cleaning.

What are your thoughts on this engine, what would it be worth? I have seen pictures and I did not notice any damage. Thanks

Jon

I think I would avoid that one. The early 120s were some of the engines that gave YS's a reputation for being finicky. One of the fellows who does YS support in the YS forum here at RCU said something to the effect of not wanting to own any of the 120NCs, if I remember correctly. You'd probably get a better answer there.

If it was left with fuel in it ten years ago, you'd probably have to replace the regulator diaphragm, some gaskets, and the bearings (if rusty). I know I wouldn't pay much for it. If you buy it, you're just taking a good chance that you'll have to dump some money into it. There are plenty of good deals to be had on more recent YS engines. I bought a new 91AC (which is at least six or seven years old) last week for $160. I figured being new I wasn't taking too many chances. It showed up on Saturday and is in fine shape.

Any YS including the two strokes that old that have been run and just put away are almost certainly going to require at the least a diaphrahm replacement.

John

If you have not pulled it apart, don't just yet. Put it on a stand and try to run it providing the bearings don't feel like 50 grit sand paper. If it had YS type fuel 20/20 mix run in it you may find it's just fine. Do not put petrol based oils (after run or other) in this engine as the pump parts are silicone and will swell causing all sorts of problems. If you feel the need to use some type of after run oil, use a synthetic 2 cycle oil sparingly.

Thanks guys, I think that I will pass on it, unless the guy will sell if for really really cheap.

Jon

Who is this person?? I like my old NC 1.20s and would go up to about 100 bucks for another one. I would buy it, heat it up and roll it over A few times then do A strip and clean and install A new diaphrahm and plunger plus A gasket set. In my case just the parts are worth more then that. I do like the new YS engines A lot better then the older ones but the prices of the new YS, OS and Saitos have gotten beyond my means. I have been going back to gas engines for A number of reasons now, glow fuel prices are one of the reasons.[&o]