Most switches are only 15a too. Make sure you're not over that. Most 3/4hp 110v motors are around 10a, because i=v/r and all.

 

Was going to mention that as well. I would consider a 20A switch. Go to your local store and make sure that the switch you put in has a HP rating on it of at least 3/4 HP. The cheapest ones will not have a HP rating, as I understand. 15A may, 20A will almost certainly. It's not just the rating of current, as that assumes making and breaking loads that are mostly resistive, which is easy on contacts. The motor will be harder on contacts, thus the need for a HP rated switch.

DNMAKINSON

EDIT: I realized that I wrote that assuming that you would replace the switch, which may not be necessary, but it would not surprise me if it were needed. Possibly you could look at the switch that is there and see if it has a HP rating on it. [open the circuit breaker first]