Dave, I have a YS 140 that I am not sure if it is an L or an fz. The original owner said that it is an FZ but the box that it came in says 140 four cycle LIMITED ys0095. It does have the 2 nipples on the back but so does some of the FZ engines. It doesn't have the mount that some of the L engines came with. Could possibly tell me how to tell the difference even if I have to open the engine. I took the head off and it doesn't have the piston with the 4 pins. Any info would be well appreciated.

I just want to say that over the last season I have gone YS crazy, I had 1 SC that had been sitting unrun for years and once I ran it I have been hooked. I now have 2, 120SCs,
2x fz63 s, 1x 160, 1x ys140, 1x 120nc and 3x heli motors I did have the heli motors already. All these motors run great and never cut off unless out of fuel.

You guys do a great job.
Thanks in advance
Jeff

All of the L engines had the three hole mount in the center of the backplate, however the part number you gave is correct for the L engine. The FZ did not have a crankshaft ring, the L did. You must pull the entire backplate off the engine to see it. The front of the crankshaft counterweight has a full disc with two split rings sitting in a bronze cup which surrounds the rear bearing forward of the crank. If the bronze cup is not there, the engine is not an L. Tough to see what you're looking for, but if you study it a bit, you'll understand.

Good Luck!