The 3 hp engine could be fitted with electronic ignition or contact points. To identify which type it is, you will need to remove the fly wheel. If it is the electronic type there will probably be only the moving arm of the contacts fitted to keep the pin that contacts the camshaft in position. If it is this type you will need a replacement coil assembly.
If it has a full set of points you may be able to clean them. Otherwise buy and fit a new set.
There is a very good american site that has a video showing how to remove the flywheel and clean the points.
You could help me by telling me the engine number on your machine because my machine has a replacement fan guard with no numbers.
Ken Cocks, June 2010
