kinser5mfan

fairly new to this so be gentle............
after driving my truck a few blocks to take a friend home, i parked in the driveway and walked to the back of the truck where i could hear the turbo still moving air!! i was scratching my head when my son came up and said he loves it when my truck makes that noise. i asked who often he has heard it and he said all the time
after letting the truck sit a while i started it idled for a few minutes and had him shut it off sure enough there it was again..
so finaly my question..... is the turbi really spinning up just setting there or what am i hearing kirby

CTD01

You will hear the turbo for a few seconds after you shut off the truck. I really noticed it after I put my intake and exhaust on. I can also faintly hear it when my truck is idling.

Paul

RowJ

Turbos spin over 100,000 rpm under a load. Not sure of rpm at idle, but it does take a while form them to stop spinning after shut down.
That's why cooling down the Pyro to a min of <300* before turning engine off, is important. Without the cool down...heat soak can be serious. Have seen a spinning turbo sitting in a static oil bath (truck turned off) take a pyro reading up to 500*...well past the oxidizing temp of even good oils!

RJ

kinser5mfan

thanks just needed to check this out

sledcrusher02

get a balanced ball bearing turbo and watch how long that sucker spins aftr shutdown the motor will be cooled down when its stoped! a little stretch but close.