. . . "Do not tamper with the governor spring , links or other parts to in - crease engine speed . 19 F - 051015L Page: 20ENGINE SPECIFICATIONS SNOW THROWER AUGER DRIVE BELT HORSEPOWER 8.5 HP Adjust the auger drive belt after the first DISPLACEMENT 249 cc 2 to 4 hours of use , again about mid - BORE 75mm ( 2.970 in . ) season and twice each season thereaf - ter ( See to Belt Adjustment in the STROKE" .