Re: mercury cruiser 170 hp temp
Assuming you have a 140deg T-stat, you should be running about 30 deg warmer, or around 170...so 175 is normal.
When you say "blower", that has no bearing on the temp of the engine, it's just used for exhausting fuel vapors while idiling or prior to startup after sitting for a period of time.
As far as the hard starting, it could be a myriad of problems depending on the age/condition of your ignition, and fuel components. Culprits could be plugs, wires, carb adjustment...you name it. Give it a good "once over", check your wires, cap/rotor, plugs, ensure your carb is tight and clean.