RE: OS 46 FX rattle noise
I've got a new Webra .50 that has made "growling" noises from day one. The bearings feel like garbage, but ya know what? I don't give a rats... Out of the 3 brand new ones I bought, only 1 sounds any good. Tired of messing around sending engines back...You can check if it's bearings by putting some heavier oil (10w30 motor oil) on the bearings, and see if that quiets 'em down some. How do they feel? If they're not nice and smooth, and you can wiggle the crank more than a few thou. then it's prob. bearings. OTOH, I (and a bunch of my fellow club members) have heard a strange sort of metallic "rattling" (?) or some such odd noises for many years comming from mainly O.S.'s and we don't know exactly what causes it...Speculation runs from chamber design (mild detonation?) to the muffler, to the crank moving back and forth, etc.etc.etc.