I bought an old OS .61FSR engine from a fellow member of the other site, RC Groups. He advertised it as a good running OS FP. I informed him in an open forum that I thought the engine was an FSR and not an FP as he had posted a pretty good picture. But I bought it anyway because he assured me it was a good running engine. It arrived with no rear bearing, no drive washer, the top of the piston damaged from someone grabbing it with a pair of pliers or some other tool and distorting the top of the ring groove, the ring was seized in the groove, head bolts were missing, and various parts were missing from the carb (a 7D). But this was a good running engine. RIGHT!!!!!!!!!! Anyway, I have always wanted a .61FSR, so I decided to make a project of this engine. I bought a bearing set from Boca, a ring from Frank Bowman, a drive washer and woodruff key from My Atomic (not listed for a .61 FSR but Igambled that any OS drive washer with a 5/16 hole in it and woodruff key with a blunt end would work, and they did), and now I have the information I need for the carb parts that were missing. I installed the new bearings and ring in the engine and took some head bolts from an old FP engine. Then I received the drive washer and woodruff key and installed them. The engine fired up almost immediately, but runs poorly, probably due to not being able to adust the low speed valve on the carb. I have now ordered the pieces of the carb that were missing, thanks to the information in this thread, I still need a carb barrel insert as this carb arrived sans the insert, but Tower does not list the insert. Does anyone have one lying around or know where I can get one? It will run without it, I'm confident, but probably run better with one in it. I am determined to get this thing running right and have spent more money on missing/damaged pieces than I paid for the engine. Once you start on a project like this, where do you quit? If I stop, all the money I have spent will be thrown away. The really ironic part of all this is that the seller informed me that he had removed a couple of my responses from the thread as they were misleading. I MISLEAD SOMEONE? The only response I had ever made was to inform him that I thought the engine was an FSR, not an FP. In RCG, the original poster in the classifds can remove any response he feels like removing. AT any rate, I look forward to receiving the carb pieces and getting this thing together and I fully expect it to run well. As mentioned earlier, I still would like to have an insert for the barrel of this carb as well as a muffler for it. The muffler is an OS 744 of which there are two versions. One version fits the FP and has threaded ears on the mounting flange. The version for ths FSR does not have the threaded ears on the flange and the holes are closer together and are not threaded. Anyone have one he would like to sell?