I checked my spring, it's looks fine and when the PS does slip, I still have spring tension on the rope. I also measured, you are correct, it's 8mm diameter. The PS assembly was replaced with a new OWB and it started slipping after just a few runs. I did not replace the shaft but will try that next. Should I replace the OWB agian even though it has like no time on it? I agree with you on the Duratrax, it's cheaper in price and also made in Japan, so most likely same quauity - or lack there of. I was looking at the electric starter drives, they use a different housing but still use a OWB and the shaft so Iwould still help the same problem, correct? Thank you for the quick help too!!!