I have an early model YS 120SF that has been sitting around for a few years and now needs help to be revived. It ran strong when I put it away years ago, but now it won't start unless I force feed fuel to it, and then only for a couple of seconds. I replaced the fuel pump diaphragm. The check valve and fuel filter seem to be working OK. Is there someplace I could send it for a thorough checkout and repair if needed?[]