Troubleshooting Engine Noises and Vibrations (Cont.) Cooling System ‰ Supply pump. ‰ Loose belts and/or pulleys. ‰ See Cooling System on page 84. Mountings ‰ Loose, broken, or worn engine mounts. ‰ Loose lag screws holding mounts to stringer. Crankshaft Balancer or Flywheel ‰ Loose bolt(s). Alternator ‰ Loose pulley and/or worn bearings. ‰ Loose mounting bolts. 7743722 - Downloaded from www.volvopenta.com 13/05/2008 20:17:06 Sterndrive ‰ Failed U–joints or gimbal bearing. ‰ Damaged internal drive components. ‰ Worn, bent, or broken propeller hub or blades. ‰ Loose, worn, or damaged engine coupler. Engine Overheats Check:
‰ Actual engine temperature by verifying with an accurate thermome- ter. ‰ Gauge operation and wiring circuit. ‰ Sending unit operation and wiring circuit. ‰ Supply pump, circulating pump, and belt(s). ‰ Water intake screens–for blockage. ‰ Thermostat. ‰ Water supply hoses. ‰ Engine timing. ‰ Water leaks on pressure side of supply pump. ‰ Air leaks on suction side of supply pump. ‰ Engine compression. 108 VPA 7743722 English 10-2004