I have a 1990 Four Winns Freedom 170 with a 2.3 L OMC (Ford Motor). It was under cover and not used for a few years. Last year we prepped it for use and had several issues from it sitting. All of those issue were fix, except for one. It has a new belt, water pump impeller, rebuilt carburetor, new cap, points and coil, and plugs. The engine compression is fine. On the trailer, with the hose supplying water to the out-drive, the engine starts and runs fine. My 2.3 was never the smoothest running engine at ideal. When I shift into gear, the engine runs very rough then stalls. This happens when shifting in to forward or reverse. If I disconnect the ESA unit, the engine doesn't stall when shifting. It just replaced the ESA unit and I still have the same problem.