What was found
AT ROTATION + INITIAL CLIMB OVERLY STRONG FUMES / ODOR ENTERED THE CABIN + FLIGHT DECK. LASTED ABOUT ONE MINUTE + GRADUALLY DISSIPATED. NOTICE A SIMILAR ODOR WHEN #2 ENG WAS SHUT DOWN DURING TAXI - IN. GROUNDED - YES. AIR TURNBACK - RECEIVED TURNOVER FROM FLIGHT CREW, CREW STATED FUMES WERE SO BAD THEY ALMOST USED O2 MASKS. FUMES DISSIPATED MOMENTS BEFORE DONNING OF MASKS. FWD FLIGHT ATTENDANTS DID NOT SMELL BUT AFT FA'S AND PASSENGERS SMELT FUMES. ACCOMPLISHED AMM TASK 21-00-01-100-801 UP TO STEP E (8). STINGER REMOVED. NO FUMES NOTED DURING PACK OPERATION WITH APU BLEED. ACCOMPLISHED ENGINE GROUND RUN DUCT PURGE PER EA# PWRPL-71EA-11276. OPERATED #1 ENGINE BLEED, #2 ENGINE BLEED AND APU PNEUMATIC. NO SMELL OF CONTAMINATION FROM CABIN AND FLIGHT DECK NOTICE.