on the Kohler's, get the engine number and call Kohler directly--ask them if there's any upgrade for the ignition modules. Some of them had a kit that was to be installed; replaces both coils with updated ones that to my knowledge, don't fail. Kubota had a part number for SOME of the Kohler engines on the smaller Z 100 series mowers that might work. Just depends on what coils you already have. There's MDI coils and there's DSAI coils. The DSAI's are failure prone.