Does it stall or just stumble? Cutting out is unclear on what it is actually doing. Most all intermittent problems are normally wiring or connector related. Put a timing light on each plug wire and see if it is spark related when it has the problem. The first step to troubleshooting the ignition is go through the wiring completely. Sand all grounds metal to metal. Pull all connectors apart and clean inspect the pins with electrical cleaner and use dielectric grease to put them together. if the pins are not all the same length use a small jewelers screwdriver to push them all the way in from the backside. Clean all the lug connectors with a wire brush and get nice and snug. Inspect all of the wires for breaks, cracked insulation and bare wires, fix as necessary. This is all part of preventive maint and should be done periodically especially after taking out of storage and preping for the summer.