Compression Ignition Addict
Join Date: Dec 2009
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The following is from BD Power Turbo cool down timer:
""A typical turbocharger can spin in excess of 100,000rpm under load, which will continue spinning when the engine is turned off.""
""The turbocharger is lubricated and cooled by the engine oil, and when the engine is turned off, that oil supply is cut off. If a turbocharger is still spinning at a high RPM when the oil supply is cut off, the internal bearings will utilize what remaining oil is around them then start to heat up - essentially cooking the oil, which causes premature bearing failure. By allowing the turbocharger to slow down to a safe RPM, this bearing failure can be prevented.""
""A very efficient means of gauging a safe time to turn the engine off is by the exhaust temperature. The suggested temperature range to go by is below 400°F (with the thermocouple mounted post-turbo). The further away the probe is away from the turbocharger, the lower the shut-off temperature should be. If the thermocouple is mounted pre-turbo, then the shut-off temperature can be higher.""
Last edited by amdriven2liv; 05-31-2010 at 10:18 AM.