Re: oil gas mix for 4hp Yamaha
A lot of smaller Yamahas used 100:1, but even then I advise 50:1. At 100:1 there isn't enough oil left over to protect the internals from rusting.<br /><br />Had a customer bring one in once. Started okay, but it was gutless. Tried this, that, and the other thing with no success. Finally pulled the head and found that the sleeve had rotated in the block from an overheat once upon a time. Heated it up, spun the sleeve back in place. Worked, but don't know if it lasted. Nothing to do with your question.
