Look after that turbo!

Walking back into the office after lunch a guy pulls in and parks his brand new Focus RS. As he pulls in he does a gratuitous throttle blip which gives a nice burbling, crackling sound. But the he sits there for the next 30 seconds revving the hell out of it then letting it crack and pop down again before revving the nuts off it again. Then he just shuts it off!! I can just imagine the red hot turbo still spinning at 200,000rpm with no oil. He might be fine this time. But if that's his regular shut down procedure he's going to one of those people who complain that Turbo's are unreliable in a few years time.

There's no need to idle for a few minutes before shutting it off, but that is indeed a meathead way to treat your car. I usually just tell people to drive like a responsible member of society for the last mile of their trip.

I live down a half mile of dirt road. I consider that the cool down time. In the Esprit (RIP), you couldn't go faster than about 15 MPH. The RAV4 can do better over it, but I take it easy. Also, the RAV4's Caldina motor will make boost at under 2K RPM, so it is actually pretty hard to not have some boost, especially going up hill.

Adrian_Thompson wrote: Walking back into the office after lunch a guy pulls in and parks his brand new Focus RS. As he pulls in he does a gratuitous throttle blip which gives a nice burbling, crackling sound. But the he sits there for the next 30 seconds revving the hell out of it then letting it crack and pop down again before revving the nuts off it again. Then he just shuts it off!! I can just imagine the red hot turbo still spinning at 200,000rpm with no oil. He might be fine this time. But if that's his regular shut down procedure he's going to one of those people who complain that Turbo's are unreliable in a few years time.

Yup.

I always wonder if my letting my diesel idle for a few minutes before shutting it down is necessary? I never even thought about it when I had my 92 Dodge Cummins, but now so many years later I'm concerned about it with the Delica. I usually drive a bit easier for the last mile or so before I get to my destination, and then idle for a few minutes. Then I worry about when I go somewhere, and have to stop for 5-10 minutes and then leave again if I should just let it idle, or not even worry about it?

Age and use are important to consider. The 1370 Case tractor I lived in as a teen was built in 1975, and it got a minute at 1000rpm, then a minute at low idle before it got shut off. That was an air cooled turbo, worked hard for ten hour periods.

My 03 XC90 has two tiny water cooled turbos, and I figure the time getting from the highway to my driveway is sufficient.

No throttle blips before shutdown, though.

Mazdax605 wrote: I always wonder if my letting my diesel idle for a few minutes before shutting it down is necessary? I never even thought about it when I had my 92 Dodge Cummins, but now so many years later I'm concerned about it with the Delica. I usually drive a bit easier for the last mile or so before I get to my destination, and then idle for a few minutes. Then I worry about when I go somewhere, and have to stop for 5-10 minutes and then leave again if I should just let it idle, or not even worry about it?

Is it a water cooled or oil cooled turbo? Water cooled ones are very forgiving, and most modern cars have them. Older cars are a little more sensitive to heat soaking, but if we're talking normal driving with minimal boost for the last few minutes and you weren't driving hard immediately before, you can shut it down right away. If you just did an autox run, I let it idle about a minute before shutdown. After an HPDE session, I do a lap of the paddock at idle with the hood popped, then maybe a minute more idling and shut down depending on how big the paddock is. This is on a BMW with an oil cooled turbo that sees 280 degree oil temps on track, and I've got 60k hard miles on that (used) turbo with zero problems.

Yes, I know I need an oil cooler....

The MS3's manual says just not to drive it like an shiny happy person for two minutes prior to shutdown.

I usually just drive it around without it making boost and shut down.

Some of the new ones trigger the water pump to keep running on shutdown to cool the turbo I believe.

Oil cooled turbo on my Delica. Later ones got oil and water cooled, but mine is an 89. No auto-X in a Delica.

How could a water pump be triggered with the engine shutdown?

Mazdax605 wrote: How could a water pump be triggered with the engine shutdown?

Electric water pump + turbo timer.

Electric water pumps are a real thing?

In reply to Mazdax605:

Yep. ze Germans started using them on their high-end models for rear heaters and the like, so the technology has been adapted to other solutions.

My 88 944 Turbo S had an electric water pump to provide cooling after shutdown. The less expensive replacement is from a Mercedes rear heater solution with a simple electrical connector change.

On my old Turbo-dodges they simply designed the water cooling solution for the turbo to work via convection after the engine was turned off (it is primarily cooled via the oil while running). Worked well enough for the warranty period (for the most part).

I recall reading some of the newer turbo cars are designed so the water cooled turbo will thermosiphon coolant through it after shutdown, thus preventing such abuse from hurting things.

My 1988 TurboCoupe always got 30 seconds between start-up and movement and from movement to shut-down. It seemed to help me be a bit more zen in my life and the engine/turbo was still strong when I sold it at 250,000 miles.

Semi related. I want to get a Pyrometer for my Delica. I've read on the Delica forum that a 2-1/16 round gauge will mount in the dash pod that houses the inclinometer,altimiter,outside/inside thermometer. The thing is nobody seems to want to answer me when it comes to what brand of pyrometer to buy. I had an Isspro in my Cummins several yeards ago, and I loved it, but they're pricey, and maybe not the best for a rinky dink 2.5 litre Japanese diesel. Can you guys recommend a pyrometer that is good, but won't break the bank. I don't care if it's analog or digital. Digital might be easier to read however.

I bought an EGR blanking plate, and plan to install the EGT probe in that as it is the only real place for the probe according to the forum. I believe 1/8" npt is the standard probe size.

Chris

Posted this yesterday then forgot about it!!

While I agree that these days you don't need to sit there for 30 - 120 seconds to let the turbo slow down before shutting of, this guy was revving the nuts off it to listen to the popping and banging, then shut off immediately. Having seen that what's the bet he does the same thing on start up.

While it may not be necessary the first and last thing I do when getting in/out of a car is start it. That way while I'm doing up, undoing seat belt, placing/gathering my phone and anything else I'm carrying it has a few moments of idle. It's just part of who I am.

Under no-load conditions the turbo shouldn't generate any boost, so while it appears that he's doing the wrong thing, in fact, that shouldn't be bad for the turbo at all. Though modern water cooled turbos don't coke the oil like in the olden days.

Zomby Woof wrote: Under no-load conditions the turbo shouldn't generate any boost, so while it appears that he's doing the wrong thing, in fact, that shouldn't be bad for the turbo at all. Though modern water cooled turbos don't coke the oil like in the olden days.

It may not be building boost but it's still spinning along at a pretty good clip so revving it up and then cutting the oil supply but shutting the car of still isn't a good idea.