I just bought a pontoon with a 1987 70 hp Tohatsu. When I turn the key to start, the bendix engages for a second or 2, then drops down. With the short time it turns the flywheel, it takes 20 or 30 tries to start from cold. It seems to run OK after starting, although it idles roughly. Can anyone tell me why the bendix does not stay engaged while the key is turned? Thanks.