E90Post
 


 
BMW 3-Series (E90 E92) Forum > BMW E90/E92/E93 3-series General Forums > General E90 Sedan / E91 Wagon / E92 Coupe / E93 Cabrio > BMW coolant freeze point question



Reply
 
Thread Tools Search this Thread
      11-30-2012, 07:39 AM   #1
EQUANT
First Lieutenant
4
Rep
310
Posts

 
Drives: 320d
Join Date: Dec 2009
Location: Bucharest

iTrader: (0)

BMW coolant freeze point question

Hi guys,

I have some OE BMW coolant around and it says on the bottle that a 50:50 mixture will give you a -40*C freeze point, so i decided to test it out.

I poured in a small recipient equal amounts of antifreeze and water and then tested the mixture. It said -18*C!

I repeated the process, put same amount of antifreeze, but half the amount of water - and it reads -25*C!

I don't understand, what's wrong?! How do i get it to read below -30*C?
I used the same tester to test a fresh mixture of antifreeze on another car (Peugeot 207) and it reads precisely -37*C, as it should.

I tested the bmw antifreeze alone and the tester goes off the scale, so it's concentrated, not pre-diluted.

Any thoughts?
__________________
BMW 320 dA LCI, BMW PPK - 197HP, 2010, sapphire black, steptronic
Appreciate 0
      11-30-2012, 07:41 AM   #2
N8N
Lieutenant Colonel
N8N's Avatar
United_States
23
Rep
1,565
Posts

 
Drives: 2009 E92 335i 6MT
Join Date: Sep 2012
Location: Sterling, VA

iTrader: (1)

Send a message via AIM to N8N Send a message via MSN to N8N Send a message via Yahoo to N8N
if you are using an old ball tester it is calibrated only for ethylene glycol type coolants. I don't know what the BMW coolant is but it may be propylene glycol, OAT, etc.

The tester works by reading the specific gravity (density) of the coolant/water mixture and it is ASSuming that you are using a mixture of EG and clean water - but the SG vs. freezing point graph will look different for different types of coolants.
Appreciate 0
      11-30-2012, 07:51 AM   #3
EQUANT
First Lieutenant
4
Rep
310
Posts

 
Drives: 320d
Join Date: Dec 2009
Location: Bucharest

iTrader: (0)

Here is the label on the BMW antifreeze and a picture of my tester. Antifreeze has ethylene-glycol and the tester says it's good for Ethylene-glycol.
Any other thoughts? winter is coming and i'm not comfortable with ~ -18*C that it's indicated with the current antifreeze, as temps may go below that.


__________________
BMW 320 dA LCI, BMW PPK - 197HP, 2010, sapphire black, steptronic

Last edited by EQUANT; 11-30-2012 at 12:40 PM.
Appreciate 0
      11-30-2012, 09:48 PM   #4
Reznick
First Lieutenant
Reznick's Avatar
United_States
5
Rep
386
Posts

 
Drives: 2008 M3 ,2000 330
Join Date: Jul 2007
Location: Syracuse NY

iTrader: (0)

I was under the impression that the anti freeze bought from BMW was straight antifreeze and had to be mixed with water to get 50/50. If you go to pep boys and look and anti freeze you'll see some bottles marked 50/50. We buy it by the 55 gallon drum so I'm use to adding water myself
Appreciate 0
      11-30-2012, 11:36 PM   #5
John 070
Lieutenant General
157
Rep
11,513
Posts

 
Drives: 335i cpe
Join Date: Oct 2006
Location: ZSP/ZPP/ZCW

iTrader: (0)

Maybe times have changed, but a 50:50 mix is good to -34F, not C. And if you go beyond 70% antifreeze, you actually reduce the anti-freeze and anti-boil. Who the heck knows, I was always better at physics than chemistry.
Appreciate 0
      12-01-2012, 04:51 AM   #6
EQUANT
First Lieutenant
4
Rep
310
Posts

 
Drives: 320d
Join Date: Dec 2009
Location: Bucharest

iTrader: (0)

This antifreeze has to be mixed with water, 50:50, as specified on the bottle. The weird thing is that 50:50 mixture only has a ~ -18*C freeze point, which is not enough.

@John - you are right. As i said, in the Peugeot they put pre-diluted Peugeot antifreeze and measured it with the same tester and the result was: ~ -37*C (-34*F -ish).

I don't know how to get the BMW antifreeze to the same point. I will probably go to BMW and ask them to check the coolant freeze point and replace it, if necessary (although it had just been replaced at a local indy)
__________________
BMW 320 dA LCI, BMW PPK - 197HP, 2010, sapphire black, steptronic
Appreciate 0
Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

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 Off
Forum Jump


All times are GMT -5. The time now is 03:52 AM.




e90post
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST