Has anyone had the fan come on after engine shutdown?

[Artie]

Just as the titles says, parked in garage, power down and get out. I come back a couple minutes later to get something out of the vehicle and all of a sudden the fan switches on full bore, it’s loud enough I almost hurt myself jumping out of the way. It ran for a minute or so before I started the engine again for about 30 seconds and then powered down. The fan remained off after this. First time I’ve experienced this, has anyone else had this happen?

 

[Blackscreen67]

Just as the titles says, parked in garage, power down and get out. I come back a couple minutes later to get something out of the vehicle and all of a sudden the fan switches on full bore, it’s loud enough I almost hurt myself jumping out of the way. It ran for a minute or so before I started the engine again for about 30 seconds and then powered down. The fan remained off after this. First time I’ve experienced this, has anyone else had this happen?

Common built in feature which is often designed to keep cooling fluids post shut down. The coolant pump likely stays on aswell to cool turbos.

Most people that drive turbo charged vehicles have no clue how horrible it is to just drive, park, shut down the engine. Turbo no no 101 that = early turbo failures.

 

[Black]

Yup very common.
The new turbo motors are built to keep cooling for a bit to let the turbos cool after shut down.

The old days one would wire in a turbo timer so keep from damaging them.

 

[Artie]

Common built in feature which is often designed to keep cooling fluids post shut down. The coolant pump likely stays on aswell to cool turbos.

Most people that drive turbo charged vehicles have no clue how horrible it is to just drive, park, shut down the engine. Turbo no no 101 that = early turbo failures.

I’ve read this before and this is my first turbo engine, I just figured since it hadn’t t done it for the 9 months I’ve owned it that it was something it wasn’t gonna do... idk, I figured that was an thing with older turbos. I’m usually pretty easy on the throttle but I did gun it up the hill by my driveway before parking so that was enough to generate enough heat in the turbos I guess. Thanks for the response.

 

[mquick5]

Common built in feature which is often designed to keep cooling fluids post shut down. The coolant pump likely stays on aswell to cool turbos.

Most people that drive turbo charged vehicles have no clue how horrible it is to just drive, park, shut down the engine. Turbo no no 101 that = early turbo failures.

Well what is the proper shut method?

Sent from my SAMSUNG-SM-G870A using Tapatalk

 

[JExpedition07]

Let it idle a little before shutdown.

 

[Artie]

Does the 2018 3.5 ecoboost have separate reservoir for the turbos or is it all the same cooling system as the engine?

 

[Blackscreen67]

Does the 2018 3.5 ecoboost have separate reservoir for the turbos or is it all the same cooling system as the engine?

No, it's a full system flow.

The center sections are journal bearings which essentially free float on incredibly thin layer of oil.

The coolant helps cool this center section, which assists the cooling of the oil.

What happens when a really hot turbo is shut down results in cracked CHRA(the main bearing section of a turbo) cracked exhaust housings, also can flash burn a bearing since hot oil is very thin. Remove new cool oil flow quickly, and you just cooked your turbo.

Good rule of thumb is 3mins cool down prior to shutdown.

I've even trained my wife to do this. She understands not to drive heavy til the engines up to temp as well.... the twin turbo X6M was her daily before I got her the expedition.

She and I are a match made in twin turbo heaven.

 

[Artie]

No, it's a full system flow.

The center sections are journal bearings which essentially free float on incredibly thin layer of oil.

The coolant helps cool this center section, which assists the cooling of the oil.

What happens when a really hot turbo is shut down results in cracked CHRA(the main bearing section of a turbo) cracked exhaust housings, also can flash burn a bearing since hot oil is very thin. Remove new cool oil flow quickly, and you just cooked your turbo.

Good rule of thumb is 3mins cool down prior to shutdown.

I've even trained my wife to do this. She understands not to drive heavy til the engines up to temp as well.... the twin turbo X6M was her daily before I got her the expedition.

She and I are a match made in twin turbo heaven.

Thanks for the info. I’m religious about taking it easy from start up to about 175° trans temp, that’s the only actual readout gauge I have but I’m pretty sure that’s a safe temp by that point. Upon shutdown I usually sit for 40 seconds to a minute but that’s not always possible sitting with two kids in the car. I guess it’s f there is a failure that’s what warranty’s are for but that won’t be much comfort if I’m on a vacation or something.

 

[Blackscreen67]

Thanks for the info. I’m religious about taking it easy from start up to about 175° trans temp, that’s the only actual readout gauge I have but I’m pretty sure that’s a safe temp by that point. Upon shutdown I usually sit for 40 seconds to a minute but that’s not always possible sitting with two kids in the car. I guess it’s f there is a failure that’s what warranty’s are for but that won’t be much comfort if I’m on a vacation or something.

Nah your safe.... that's what the after shutdown system is there for!