3 things my mechanic said will help a turbo last longer

[supton]

Is there a need to define a goal here? I mean, no one likes parts breakage. but what is an acceptable level of breakage? Is 200k and then it can break ok? Or is "never" always the right answer? A number of these cars with turbos would not nearly be as fun as having a larger NA instead under the hood (weight distribution, peak power, mpg).

I got 255k out of the only turbo I owned, and I was kinda glad when it went... 'cuz I could then justify putting in a bigger one. That got 10k OCI's for the first 100k, lengthening out to like 12k at the end. Went back to 10k after that, because I beat on that car like a redheaded stepchild after that.

In my case the shaft snapped, not sure why, but it clearly sheared between the wheels. Maybe it got lugged too much, I guess it can suddenly spin backwards under some loading conditions?

 

[SHOZ]

On my Genesis Coupe 2L T with 135k miles on it is still putting out 22lbs peak, using Mobil 1 and 5k oil changes, Fram ultra at 10k changes.

They have both oil cooling and water cooling. The water cooling is passive and will reverse flow after the engine is shut off due to the turbo heated coolant rising though the turbo, from the water pump, goes on to the heater core and on to the coolant manifold on the back of the head as the high point.. On the models with the water/oil coolers the coolant is drawn up through the oil cooler after the water pump and before the turbo.

Works like a charm.

 

[2005jettatdi]

I had a 2001 Dodge 2500 with the Cummins and 5 speed manual. I had a pyrometer installed on it so I would know since I had a farm then and sometimes it had to work pretty hard. I found that driving down my .4 mile long drive way cooled it off just fine. I found that down shifting as I went into a rest area cooled it nicely, most of the time. I found it took a few minutes to cool off in other situations. I only used Mobil 1 TDT in the pickup.

So, I applied what I learned to driving the Jetta. Almost 17 years and it seems to be working. I had to replace the turbo, but it was not from coking or other overheating.

 

[Mainia]

Yes the sound is there, but none have an electric waterpump. well, the electric konas do of course...

I know none have an electric water pump....... God NO, I never thought it had an electric water pump, who wants another place where a Hyundai can start a fire....Ha ha. What is that sound? Again it sounds to me a slow bleed off of the high pressure fuel circuit? You just can't purge all that PSI in 2-3 seconds, I can see slowly revealing pressure in 30 seconds.

 

[Jetronic]

The high fuel pressure should stay present if the injectors are all good, they rarely are. It's vacuum bleeding away I believe.

 

[SAJEFFC]

The one scenario I can see where a turbo cool down is needed is when you have been driving on the freeway for a while and get off at a rest area where there is not much time for things to cool off. That said, I don’t think you need to worry much about modern turbos.

I agree with the other two points.

What I do with my new '21 F-150 3.5 eco hybrid when pulling in to a rest area is shut it off, get out and lock it, then remote start it right away.
You can go do your business and relax a minute and the truck is happily idling away cooling down. I always did this with my Super Duties as well when pulling a 43 ft fifth wheel RV. The truck is locked and secure and the turbo is getting all the oil it needs while cooling down.

 

[tnt_motorsports]

Always use full synthetic, never go longer than 5K miles on an oil change, and let the engine idle for 10 seconds before shutting it down...have you heard similar?

on my Cummins Ram I let the truck idle down. The turbine will spin for some time after the engine is shut off and no oil flow, so not letting the engine idle the turbo spins longer. I also watch my EGT's and let the truck get down to less than 400F prior to shutting it off. I use Mobil Delvac 1300 (conventional) in my truck and change when the OCI comes on, usually at 7.5K miles. According to UOA I am going to try 10K.

just my $0.02

 

[CKN]

I think we determined the OP's mechanic at least when it comes to modern Turbos doesn't know what he is talking about.......

 

[Al]

My Forester XT always shows you how much boost you are using. Its only on boost (< 5 psi) maybe 20% of the time. The other times it is actually windmilling (cooling) and the gauge reads like up to -11psi. I think Subaru is the only company that does this. They have been turboing since at least '91

 

[y_p_w]

The whole idea of a cool down at idle was to let any residual energy in the turbo reduce to a minimum, in addition to having oil flow to take away heat. If it's water cooled, that will give a few seconds more of the coolant taking away even more heat.

I'll let it cool down in my WRX for a few seconds, but it's hardly an issue that I worry about unless I just got off the freeway, which will spin up the turbo as there's no way to turn it off. But as others said, modern water cooled turbos don't have a problem with an immediate shutdown. It requires a high coolant tank where the coolant temperature is low. It creates a thermal siphon that draws heat from the coolant system through the turbo housing. It's not going to slow down the the bearings, but my understanding is that the real reason for coking is the excessive heat.

Water Cooling For Your Turbo

Water-cooling improves mechanical durability and lengthens the turbocharger’s life. Garrett GTX and G Series ball bearing turbos are designed to be cooled

www.garrettmotion.com

The physical process of turbocharger water-cooling is an interesting one and works in a different way than what might seem obvious. It is true that during normal engine operation water flows through the turbocharger mostly due to pressure created by the engine’s water pump. However, an additional phenomenon known as “thermal siphoning” pulls water through the turbo’s center housing if the water lines are properly routed, even after the engine is shut off and the water pump is no longer pumping.​

​

Heat in the center housing is transferred to the water via conduction, like the cooling effect that occurs inside a typical water-cooled engine (with a water jacket surrounding each cylinder and running through the cylinder head). If the water running through a turbocharger is allowed to escape freely after absorbing heat, it will rise through the cooling system pulling cooler water into the turbocharger along with it. In this way, the intense heat that has soaked back into the turbo after engine shutdown is wicked away from the bearings and seals, and prevented from causing serious damage without assistance from the engine’s water pump.​

 

[gathermewool]

Engine-braking while coming off the highway and putting about to find a spot to park is all I’ll ever give the turbo to cool down. The only time I questioned that logic was with my previous STI. I hammered on it all up the gunks and then parked. Even with the idle time to buy a parking ticket thr bubbling was still very audible upon parking and shutting it down. Still wasnt worried.

My Forester XT always shows you how much boost you are using. Its only on boost (< 5 psi) maybe 20% of the time. The other times it is actually windmilling (cooling) and the gauge reads like up to -11psi. I think Subaru is the only company that does this. They have been turboing since at least '91

All turbo-charged vehicles will be in vacuum when boost isn’t commanded. This is not a Subaru thing.

What year do you have? My 14 with the FA20DIT is always on the verge of positive boost on the highway, hovering between -2 to +2# due to hills and wind variance.

A boost reading of -11# means you’re engine-braking at full vacuum or idling, also at high vacuum. My car will show slightly higher vacuum of -11# (I’ve never seen higher vacuum) while engine-braking than while idling (Usually around -10#)

/

The FA20DIT cools passively. The turbo is beneath the engine, so natural circulation without an additional top reservoir is possible.

I still love our FXT. I hope it (and the turbo) last is a very long time.

 

[GMBoy]

Always use full synthetic, never go longer than 5K miles on an oil change, and let the engine idle for 10 seconds before shutting it down...have you heard similar?

Been doing that exact regime since 1987 when I got my Buick GN new off the lot. I always and still do run Mobil 1 at 5k mile intervals or 1/yr. Since the car is still like brand new and only 65k miles I probably only been putting 1000 miles a year on it. But I always let it idle almost a minute before shutting down because its old school oil cooled only. The turbo is still original.

 

[grampi]

I think we determined the OP's mechanic at least when it comes to modern Turbos doesn't know what he is talking about.......

How so?

 

[CKN]

How so?

You don't have to idle down motors to spool down the Turbos-the systems does it on it's own when you turn off the motor.

 

[dishdude]

I think cooling down the turbo was something needed before they were all intercooled, something like the old Chrysler turbo I 2.2. Not a thing with modern turbos.

If I was running it really hard I'd probably let it idle for 30 sec or so before shutting it down, but completely unnecessary for normal driving.

 

[grampi]

You don't have to idle down motors to spool down the Turbos-the systems does it on it's own when you turn off the motor.

So what's wrong with taking the extra measure? No harm, no foul...

 

[64bawagon]

The guys at work used to whine and argue about a short cool down time. I finally took every owners manual for every diesel engine we had and handed every person the policy with the 5 pages straight out of the manuals. Detroit diesel 2 stroke and 4 stroke, Cummins, Mercedes etc
My question was "do you know more than the people that designed, built and warranty that engine" ?
The only turbo's we ever had fail were on trucks that we inherited from another organization that never idled the truck, they drove them very hard and shut them down hot and then wondered why they kept grenading turbo's

 

[brages]

I think cooling down the turbo was something needed before they were all intercooled, something like the old Chrysler turbo I 2.2. Not a thing with modern turbos.

If I was running it really hard I'd probably let it idle for 30 sec or so before shutting it down, but completely unnecessary for normal driving.

I don't think it was the intercooler -- a lot of the very early turbos were not water cooled, and I think those early turbos got a bad reputation for coking up and premature failure.

 

[CKN]

So what's wrong with taking the extra measure? No harm, no foul...

Drive an F-150 w/one of the turbo motors. Turn off the motor. You will hear something running that is cooling off the Turbo. It is NOT NEEDED. Your mechanics thinking is that of 40 years ago.

 

[CKN]

Your mechanic is spot on, but it may take longer than 10 seconds to cool down. I've heard 1-2 minutes.

I only let my Volvo 940 cool down if I'd been dogging it. At 24 years old it ran fine.

The F-150's probably don't run more than 15 seconds after you turn off the motor....BTW-somehow I would expect BITOGers to go along with 40 year old thinking,,,,,,