speeds up to 75,000 rpm. Therefore, it is ofutmost importance that turbochargers be main-tained in proper working order at all times. If aturbocharger is allowed to operate withoutlubrication, cooling, or the proper clearances, itnot only could be completely destroyed in amatter of minutes but also could possibly causeextensive damage to other machinery andpersonnel.All oil lines and air duct connections shouldbe inspected and free of leakage. The air filtershould be clean and in place and there should beno build-up of dust or dirt on the impeller. Turnthe impeller by hand and check for binding or rub-bing and listen for any unusual noises.When the turbocharger is operating, listen forany unusual noise or vibrations. If you hear ashrill high pitch whine, shut down the engine atonce. The whine may be caused by a failingbearing, and serious damage may result. Do notconfuse the whine heard as the turbine runs downwith that of a bad bearing.Noise from the turbocharger may also becaused by improper clearances between theturbine wheel and the turbine housing. Theclearances should be checked at predetermined in-tervals in accordance with the PMS. Checkbearing axial end play and shaft radial movement.Crankcase vents should not be directed towardsthe turbocharger air intakes, as the corrosive gasesmay cause pitting of the blades and bearings,thereby reducing the life of the turbocharger.Chapter 3—ENGINE MAINTENANCE3-41
Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business