OMRG25204 oem uncert & tier 1.pdf - John Deere Industrial Engines

Lubrication & Maintenance/250 Hour/6 MonthManual Belt Tensioner AdjustmentNOTE: Two types of manual tensioners shown.NOTE: Inspect belts for cracks, fraying, or stretched-outareas. Replace if necessary.As a reference check, twist belt in the middle of a254—305 mm (10—12 in.) span with two fingers.A properly tensioned belt will turn 75—85degrees. If belt turns more, it needs to betightened. If belt turns less, it needs to beloosened.NOTE: If timing gear cover or alternator bracket interferewith installation/centering of belt tension gauge(A), install gauge with face toward engine.Check Belt TensionRG10556 –UN–21DEC991. Install JDG1341 Belt Tension Gauge (A) on belt,halfway between pulleys as shown. (JDG1341 BeltTension Gauge available from local John Deere Dealeror Distributor.)2. Loosen cap screws (B) and (C).3. Slide alternator or tensioner bracket (D) in slot by handto remove all excess slack in belt.IMPORTANT: Do not pry against alternator rear frame.4. Stretch belt by prying outward on alternator front frameor tensioner bracket. Observing tension gauge, stretchthe belt until specified tension is achieved.A—Belt Tension GaugeB—Cap ScrewC—Cap ScrewD—Tensioner BracketAdjust Belt TensionRG10557 –UN–21DEC99SpecificationNew Belt—Tension.................................470—650 N (105—145 lb-force)Used Belt—Tension..................................400—580 N (90—130 lb-force)5. Tighten cap screws (B) and (C).NOTE: After ten minutes run-in, new belts are consideredused. Belt tension must then be rechecked perused belt specifications.6. Run engine for ten minutes and immediately re-checkbelt tension per used belt specification above.7. Reset belt tension as necessary.OURGP11,0000008–19–24JUN04–1/130-7 110306PN=78