Does the compressor have an unloader that allows the motor to spin up to speed before it starts compressing? If not, one should be installed. Are you running 120 or 240 volts? A 5 HP motor on 120 is sending a boy to do a man's job.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!