Welcome to Bimmerfest -- The #1 Online Community for BMW related information! Please enjoy the discussion forums below and share your experiences with the 200,000 current, new and past BMW owners. The forums are broken out by car model and into other special interest sections such as BMW European Delivery and a special forum to voice your questions to the many BMW dealers on the site to assist our members!

Please follow the links below to help get you started!

Go Back   Bimmerfest - BMW Forums > BMW Model Discussions > 3 Series / 4 Series > E90/E91/E92/E93 (2006 - 2013)

E90/E91/E92/E93 (2006 - 2013)
The E9X is the 4th evolution of the BMW 3 series including a highly tuned twin turbo 335i variant pushing out 300hp and 300 ft. lbs. of torque. BMW continues to show that it sets the bar for true driving performance! -- View the E9X Wiki

Reply
 
Thread Tools Display Modes
  #1  
Old 12-04-2012, 10:39 AM
jburke4689 jburke4689 is online now
Officially Welcomed to the 'Fest
Location: Ellicott City, MD
 
Join Date: Apr 2008
Posts: 596
Mein Auto: 2007 335i
Engine off Cabin Heat and turbo cooling question

In the N54 the electric water pump will pump coolant through the turbo to cool it and I believe that it will cool the turbo if required even with the engine off as directed by the DME. My question is that if you push the "REST" button to heat the interior of the car while the engine if off, does that also provide a manual method of cooling the turbo since it uses the coolant pump.
__________________
Reply With Quote
Advertisement
  #2  
Old 12-04-2012, 05:02 PM
TXFred TXFred is offline
Officially Welcomed to the 'Fest
Location: Austin, TX
 
Join Date: Apr 2012
Posts: 236
Mein Auto: 2008 335i Convertible
Quote:
Originally Posted by jburke4689 View Post
In the N54 the electric water pump will pump coolant through the turbo to cool it.
Are you sure about that? I've never heard the water pump run after shutdown. Then again, I've never listened for it. I'm not questioning your knowledge, just seeking confirmation.

One nice thing about a water cooled turbo is that, if the plumbing is done correctly, the coolant will continue to circulate through the turbo via convection. So a pump may not be needed.

I live in fear of turbo coking. At some point, I plan to add an after-oiler to my car. Here's an example. http://www.racerpartswholesale.com/p...4964/Accusumps

I plan to mount it forward of the radiator, so that when I shut down, a charge of cool oil is pumped to the turbo bearings to quickly lower their temperature.

As far as your question goes, if the water pump is running, then coolant will be circulating through the turbos.

Frederic
__________________
Any idiot can be fast in a straight line. The corners are what separates the drivers from the commuters.

Powered by corn.

Last edited by TXFred; 12-04-2012 at 05:03 PM.
Reply With Quote
  #3  
Old 12-04-2012, 05:28 PM
floydarogers's Avatar
floydarogers floydarogers is offline
Pedant and Curmudgeon
Location: Renton, WA
 
Join Date: Oct 2010
Posts: 3,700
Mein Auto: 335d, 328d, Toyota T100
Quote:
Originally Posted by TXFred View Post
Are you sure about that? I've never heard the water pump run after shutdown. Then again, I've never listened for it. I'm not questioning your knowledge, just seeking confirmation.
Mike Miller (Roundel) has confirmed it in a couple instances. He also says "it's very quiet". Sorry, can't remember which month/issue - they're up at my cabin.

As for whether the rest heat function's pump is the main one and will cool the turbo, don't know. My 335d has an auxiliary pump mounted on the left strut tower (about 8" below the top) that I understand is used on those (diesel) cars with the rest heat function - but then the M57 has a belt-driven pump. Can't find the aux pump on realoem.com for the 335i.

Last edited by floydarogers; 12-04-2012 at 05:32 PM.
Reply With Quote
  #4  
Old 12-04-2012, 06:19 PM
CALWATERBOY's Avatar
CALWATERBOY CALWATERBOY is offline
Officially Welcomed to the 'Fest
Location: San Francisco
 
Join Date: Aug 2009
Posts: 10,007
Mein Auto: 2009 E93 N54
Quote:
Originally Posted by jburke4689 View Post
In the N54 the electric water pump will pump coolant through the turbo to cool it and I believe that it will cool the turbo if required even with the engine off as directed by the DME. My question is that if you push the "REST" button to heat the interior of the car while the engine if off, does that also provide a manual method of cooling the turbo since it uses the coolant pump.

Yessir - there is 1 body of cooling water. But:

I've appreciated REST on many winter stops but don't remember turbos cooling then.

My cooling water can run through the turbos after a warm evening run, but there's no need for REST in that weather.
Reply With Quote
  #5  
Old 12-04-2012, 08:48 PM
TXFred TXFred is offline
Officially Welcomed to the 'Fest
Location: Austin, TX
 
Join Date: Apr 2012
Posts: 236
Mein Auto: 2008 335i Convertible
Quote:
Originally Posted by floydarogers View Post
My 335d has an auxiliary pump mounted on the left strut tower (about 8" below the top) that I understand is used on those (diesel) cars with the rest heat function - but then the M57 has a belt-driven pump. Can't find the aux pump on realoem.com for the 335i.
I looked under the hood of my 335i. There's no aux pump that I can see. The heater hoses run to the front of the engine. So I assume that Rest just activates the normal coolant pump.

Frederic
__________________
Any idiot can be fast in a straight line. The corners are what separates the drivers from the commuters.

Powered by corn.
Reply With Quote
  #6  
Old 12-04-2012, 10:09 PM
CALWATERBOY's Avatar
CALWATERBOY CALWATERBOY is offline
Officially Welcomed to the 'Fest
Location: San Francisco
 
Join Date: Aug 2009
Posts: 10,007
Mein Auto: 2009 E93 N54
Quote:
Originally Posted by TXFred View Post
I looked under the hood of my 335i. There's no aux pump that I can see. The heater hoses run to the front of the engine. So I assume that Rest just activates the normal coolant pump.

Yup - the electric water pump.
Reply With Quote
  #7  
Old 12-05-2012, 07:55 AM
jburke4689 jburke4689 is online now
Officially Welcomed to the 'Fest
Location: Ellicott City, MD
 
Join Date: Apr 2008
Posts: 596
Mein Auto: 2007 335i
Here is a quote from the BMW N54 Engine Management Training course on the value and advantage of the electric water pump.

Component Protection
After-running of electric coolant pump = improved heat dissipation from engine switch off point. Allows protection of turbochargers by reduced oil "coking" during heat soak.

The schematic doesn't show any valve other than the thermostat so I guess pressing "REST" must run coolant through the turbochargers.
__________________

Last edited by jburke4689; 12-05-2012 at 10:04 AM.
Reply With Quote
Reply

Bookmarks


Forum Navigation
Go Back   Bimmerfest - BMW Forums > BMW Model Discussions > 3 Series / 4 Series > E90/E91/E92/E93 (2006 - 2013)
Today's Posts Search
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On



Forum Jump


All times are GMT -7. The time now is 02:03 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
© 2001-2011 performanceIX, Inc. All Rights Reserved .: guidelines .:. privacy .:. terms