What was found
APPROXIMATELY 20 MIN INTO FLIGHT AT FL430, CREW NOTICED A HOT SMELL. 5 MINUTES LATER A WHITE GRAY SMOKE ENTERED THE COCKPIT & CABIN. THE PRESS SOURCE SELECT KNOB WAS SELECTED TO L IAW ENVIRONMENTAL SMOKE CHECKLIST. SMOKE DISSIPATED DURING DESCENT & LANDING OVER 20 MIN PERIOD EN ROUTE TO ALTERNATE AIRPORT. REMOVED RT ENG SN PCE CG0286 & INSTALLED A SERVICEABLE ENG PCE-CG0027. PERFORMED OPERATIONAL CHECKS, LEAK CHECKS & 5 POINT ENG CALIBRATION RUN WITH NO DEFECTS NOTED. ALL WORK PERFORMED IAW CE-680 MM 71-00-10, 71-00-20, 71-00-30 & PWC 306C EMM 71-00-00.