Narrative:

Aircraft first brought in for alternator belt being loose in 1999. Repeated problem. Engine overhaul and new belts put on with new alternator sheave apr/04. In nov/04; alternator belt was loose again. In mar/05 both air conditioning and alternator belts worn and replaced. At annual apr/05; found both belts worn and replaced. In jun/05; alternator belt was found loose and air conditioner service bulletin 126-2 was installed including new compressor. Jun/wed/05 alternator belt worn and alternator belt re-tensioned. Jul/wed/05; alternator belt loose. Alternator replaced and new belt installed. Jul/tue/05 alternator sheave failed due to incorrect spacer being installed. Called technical representative; company X; who advised that no spacer was required under their pulley. Mr X sent e-mails of their blueprints showing no spacer required. Purchased new alternator from cessna and new pulley. Pulley would not fit into alternator without cooling fans hitting or chafing case. 2 large area washers were used to shim to correct alignment. Once again; after 28.2 hours; alternator belt was either failing or loosening. Engine sheave and alternator sheave were checked for alignment numerous times by different a&P's and owner. Alignment was checked with engine running and alignment was good; but an up and down ripple was observed. Each time alternator was installed and rechked; there were no loose mounting bolts and tension arm ballast bolt had not loosened either. Aircraft flown to where overhaul was performed and alternator maintenance bracket was worn and took responsibility for not taking care of it at engine overhaul. Engine shop also replaced starter generator drive in which alternator sheave is located; and said bearings were worn and making metal. Starter generator drive assembly replaced with new. Alternator was installed on new bracket mount and aircraft released for service. Alternator belt checked by same shop 3-4 days later with no discrepancies. 10 days later; both air conditioning and alternator belts were shred. Alternator sheave to engine sheave alignment was found to be off 1/4 inch.

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Original NASA ASRS Text

Title: A C210 WAS RELEASED FROM ENG OVERHAUL AND DISPLAYED CHRONIC WORN AND LOOSE ALTERNATOR DRIVE BELTS. AFTER 5 YRS OF WORN BELTS; OVERHAUL SHOP FOUND DRIVE SHEAVE MISALIGNED.

Narrative: ACFT FIRST BROUGHT IN FOR ALTERNATOR BELT BEING LOOSE IN 1999. REPEATED PROB. ENG OVERHAUL AND NEW BELTS PUT ON WITH NEW ALTERNATOR SHEAVE APR/04. IN NOV/04; ALTERNATOR BELT WAS LOOSE AGAIN. IN MAR/05 BOTH AIR CONDITIONING AND ALTERNATOR BELTS WORN AND REPLACED. AT ANNUAL APR/05; FOUND BOTH BELTS WORN AND REPLACED. IN JUN/05; ALTERNATOR BELT WAS FOUND LOOSE AND AIR CONDITIONER SVC BULLETIN 126-2 WAS INSTALLED INCLUDING NEW COMPRESSOR. JUN/WED/05 ALTERNATOR BELT WORN AND ALTERNATOR BELT RE-TENSIONED. JUL/WED/05; ALTERNATOR BELT LOOSE. ALTERNATOR REPLACED AND NEW BELT INSTALLED. JUL/TUE/05 ALTERNATOR SHEAVE FAILED DUE TO INCORRECT SPACER BEING INSTALLED. CALLED TECHNICAL REPRESENTATIVE; COMPANY X; WHO ADVISED THAT NO SPACER WAS REQUIRED UNDER THEIR PULLEY. MR X SENT E-MAILS OF THEIR BLUEPRINTS SHOWING NO SPACER REQUIRED. PURCHASED NEW ALTERNATOR FROM CESSNA AND NEW PULLEY. PULLEY WOULD NOT FIT INTO ALTERNATOR WITHOUT COOLING FANS HITTING OR CHAFING CASE. 2 LARGE AREA WASHERS WERE USED TO SHIM TO CORRECT ALIGNMENT. ONCE AGAIN; AFTER 28.2 HRS; ALTERNATOR BELT WAS EITHER FAILING OR LOOSENING. ENG SHEAVE AND ALTERNATOR SHEAVE WERE CHKED FOR ALIGNMENT NUMEROUS TIMES BY DIFFERENT A&P'S AND OWNER. ALIGNMENT WAS CHKED WITH ENG RUNNING AND ALIGNMENT WAS GOOD; BUT AN UP AND DOWN RIPPLE WAS OBSERVED. EACH TIME ALTERNATOR WAS INSTALLED AND RECHKED; THERE WERE NO LOOSE MOUNTING BOLTS AND TENSION ARM BALLAST BOLT HAD NOT LOOSENED EITHER. ACFT FLOWN TO WHERE OVERHAUL WAS PERFORMED AND ALTERNATOR MAINT BRACKET WAS WORN AND TOOK RESPONSIBILITY FOR NOT TAKING CARE OF IT AT ENG OVERHAUL. ENG SHOP ALSO REPLACED STARTER GENERATOR DRIVE IN WHICH ALTERNATOR SHEAVE IS LOCATED; AND SAID BEARINGS WERE WORN AND MAKING METAL. STARTER GENERATOR DRIVE ASSEMBLY REPLACED WITH NEW. ALTERNATOR WAS INSTALLED ON NEW BRACKET MOUNT AND ACFT RELEASED FOR SVC. ALTERNATOR BELT CHKED BY SAME SHOP 3-4 DAYS LATER WITH NO DISCREPANCIES. 10 DAYS LATER; BOTH AIR CONDITIONING AND ALTERNATOR BELTS WERE SHRED. ALTERNATOR SHEAVE TO ENG SHEAVE ALIGNMENT WAS FOUND TO BE OFF 1/4 INCH.

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.