The Model # is H-050312TD. This motor has never given me a bit of trouble. I bought it new. We had it out the other day when it started missing and sputtering at about 3/4 throttle. I had been running for about 30 minutes. It had fresh 50:1 in it and I let it cool down for a while and it ran fine on the way in. Just as I was putting it in the slip at idle speed it started missing again. What gives? Any suggestions would be appreciated. Thanks