There should be no problem running a 3 blade prop.. it will run much smoother and will have more thrust than the two blade (although more drag under sail) It just needs to be properly pitched. Did you pick the prop up in a bargain bin or have it spec'd for your boat and engine?
There are several prop sizing tools on line, a little time there will give you some basic starting data.
I recommend the Campbell sailor prop as a good compromise between pricey folder/feathering props and the michigan wheels.
These guys are here in BC: West by North Enterprises