Seems as though the ignition switch on my Jinma 254 is acting up. Will not energize the glow plugs when screwed to the dash board, but does so fine when I pull it out. Problem seems repeatable and I looked for any interference behind the dash when switch is in place, none seen. Is this the way they normally go bad? I see the Ford switch is the suggested replacement, but I am contemplating using separate switches for each function, purchased at my local marine supply store. Any thoughts?