Delica Canada | Mitsubishi Van Club

My son insists that if you drive a turbo diesel, after driving you must let your engine idle for 30 seconds before you shut it off. Is this true? If so, is a turbo timer a good idea?

Given the title of your thread, instead of a turbo timer you should install a pyrometer: that way you could see how hot your turbo is, and then idle for a while before shutting down. I generally wait until it's below 400 F and then shut off.

If you are shutting down, running inside the store/house/library for 5 or 10 minutes, and then driving away again, you don't need to worry about cooling off the turbo. The problems start when you shut down for the night after flying along the highway to get home and you shut off the engine in the driveway before you stop rolling - the circulating oil doesn't have a chance to cool down, which means your turbo doesn't cool down, which means you're hardening the steel. What happens to hardened steel? Becomes brittle.

Hello neighbor as mentioned a pyrometer is a good call, until then always idle for a few minutes before shutting down.
cheers

Hi neighbour!! Yes, we're putting a pyrometer in for sure.

I do not have a pyrometer, should get one someday but I have oil thermometer. Depends on driving condition, I idle before shut the engine down for 2-5 minutes, when oil temperature drops below 80 degree C...