Auto Service Professional

OCT 2018

Magazine for the auto service professional

Issue link:

Contents of this Issue


Page 44 of 69

O c t o b e r 2 018 A SP 43 PENTOSIN FLUIDS ARE DESIGNED TO MEET THE STRICT OE STANDARDS OF THE WORLD'S FINEST IMPORTS. CHECK OUT OUR FULL LINEUP OF HIGH- QUALITY FLUIDS AT PENTOSIN.NET OR VISIT OUR ONLINE CATALOG AT SHOWMETHEPARTS.COM/CRP. Ā© CRP IndustriesĀ® Inc. All rights reserved. FROM THE FIRST FILL TO THE LAST. Circle 116 on Reader Service Card be as high as 240,000 rpm. Keeping that in per- spective, it becomes obvious that maintenance and proper installation procedures are critical to keeping a turbo alive and well. Turbo systems typically feature a compressor bypass valve (commonly referred to as a blow-off valve) on the intake side and a wastegate in the exhaust flow side. e blow-off valve is a pres- sure relief device on the intake path to prevent the turbo's compressor from going into surge. e blow-off valve should be located between the compressor discharge and the throttle body, downstream of the charge air cooler. When the throttle body closes rapidly, the airflow is quickly reduced, causing airflow insta- bility and pressure fluctuations, which lead to a surge. Surge can eventually lead to thrust bearing failure due to high loads. e blow-off valve uses a combination of manifold pressure and spring force to detect when the throttle is closed. When the throttle is closed rapidly, the valve vents boost in the intake stream to relieve pressure. Lack of proper maintenance is probably the leading cause of turbo failures. Journal and bear- ing failures are frequently caused by a lack of lu- brication. Upon examination, the sha journals will show discoloration as a result of excessive heat. Lack of lubrication may reveal a bluish dis- coloration. Bearing or journal failures can be caused by the use of oil viscosity that is too heavy for the application, or lack of lubrication resulting from a failed or blocked oil supply line. Also, even a tiny spec of dirt in an oil orifice Oil delivery port. Oil is circulated to the turbo to protect the shaft and bearings.

Articles in this issue

Links on this page

Archives of this issue

view archives of Auto Service Professional - OCT 2018