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I ordered a Loncin engine to replace my broken B&S and looks like I have a bit of a problem. Although the new engine shaft length measured from the mount points matches that of the old engine, the bottom of the sump is higher so the shaft length counted from the gasket is longer on the new engine. And here comes the spacer sleeve (part no 4) in the manual below, which is now to short to cover the shaft between the bottom of the sump and the top of V-belt pulley. I'm wondering if its only job is to prevent the top ring of the pulley from going up or does it have any other purpose? It'll be difficult to find a matching part unless it can be custom made so I'm a bit stuck and rather than moving I keep scratching my head Any one had this sort of problem and managed to figure out some solution other than ordering yet another engine?