As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR TURNBACK, DURING CLIMB-OUT COCKPIT HAD A HEAVY CHEMICAL ODOR SHORTLY AFTER CABIN BEGAN TO FILL WITH A SMOKEY MIST, SMOKE BEGAN TO CLEAR WHEN ENGINE POWER WAS REDUCED TO IDLE. PROBLEM GOT WORSE AS POWER WAS APPLIED DURING FINAL APPROACH. REPLACED THREE EACH 'A' HYDRAULIC RESERVOIR PRESSURIZATION CHECK VALVES. LEAK AND OPS CHECK GOOD. (M)