Re: Chrysler 9.9 Problem
Not to doubt you, but these small engines typically are run without a tach or a speedometer. Speed is very difficult to determine on the water. And even on a small 12 foot tin boat, a 9.9 is just not going to go that fast. Suggest that you get a friend with a boat that has a speedometer to pace you. Find out what speed you are actually going before you decide to tear into the engine. Then, if your speed is really low, check to see that it is running on both cylinders and check to see that the carb is not varnished and that the fuel pump is delivering sufficient fuel. The fuel pump on that engine is sort of triangular in shape, on the right hand (starboard) side, (Left when you are looking at it from the boat) and held together with three screws. It has a rubber diaphragm and a built in screen which may be partially clogged.
If you do not have spark on both cylinders then pull the flywheel and replace both sets of points and condensers. Set points to .020 gap. However, if it starts easily and appears to run well, then it is likely that the points and condensers are OK.
Just as a comparison, a 10 hp Chrysler on a ten foot tunnel hull boat only went about 18 MPH. So if you are anywhere close to that range, the engine is PROBABLY running correctly.
