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 > 5 Series > E39 (1997 - 2003)

E39 (1997 - 2003)
The BMW 5-Series (E39 chassis) was introduced in the United States as a 1997 model year car and lasted until the 2004 when the E60 chassis was released. The United States saw several variations including the 525i, 528i, 530i and 540i. -- View the E39 Wiki

Reply
 
Thread Tools Display Modes
  #1  
Old 12-11-2010, 09:33 PM
bluebee's Avatar
bluebee bluebee is offline
Seek to understand,^Value
Location: San Jose, California
 
Join Date: Mar 2008
Posts: 20,127
Mein Auto: 02 BMW 525i M54 auto 130K
Will the next person who replaces his expansion tank please cut it open & compare?

Will the next person who replaces his expansion tank please cut the old tank open and snap a photograph of the "natural" position of the second chamber?

See this thread for more complete details:
- Behr radiator and Behr expansion (aka surge) tank autopsy (1) (2)

So far, nobody has reported what the lower chamber does and how it operates in the photo below.

You may notice mine has a black 4-inch long slider that was locked in place (i.e., it could not slide in that position) by the black post coming down from the top of the tank.

What perplexes me is that oblong hole "looks" like the black post should have gone in that hole (to allow sliding perhaps?).

Point is, it would be very useful if the next person who replaces their expansion tank opens theirs up and snaps a picture of the position and nature of that hidden chamber so we can better figure out how it works and how it fails.

Thanks,
Bluebee

Reply With Quote
Ads by Google
  #2  
Old 12-11-2010, 09:41 PM
bluebee's Avatar
bluebee bluebee is offline
Seek to understand,^Value
Location: San Jose, California
 
Join Date: Mar 2008
Posts: 20,127
Mein Auto: 02 BMW 525i M54 auto 130K
Even though my "slider?" was locked in place by the post, I could manually, with some force exerted, move the post so that it fit into the oblong hole, and then (only then), I could move the slider, as shown in the photo below.

So, I'm wondering, if this is yet another failure mode of the expansion tank (that the slider gets locked into position accidentally).

That's why the next person who replaces his Behr expansion tank should be asked to cut it open and show us what his second (hidden) chamber looks like.

Reply With Quote
  #3  
Old 12-30-2010, 04:26 PM
bluebee's Avatar
bluebee bluebee is offline
Seek to understand,^Value
Location: San Jose, California
 
Join Date: Mar 2008
Posts: 20,127
Mein Auto: 02 BMW 525i M54 auto 130K
Here is a clarification of the question based on confusion in this thread:
- Anyone seen a defective Behr Reservoir before (2002 530i)

The question is "what is the natural position of the black slider & black stalk".

When I opened my second chamber, the black stalk was "pinning" the black slider in place such that the black slider (an upside-down hollow cup that covers both holes in the bottom of the Behr expansion tank) could not move up.

However, it "appears" that there is a "slot" in the top of the black slider that should allow the black stalk to slide into it thereby allowing the black slider to rise to the top of the expansion tank.

My question is whether or not that black stalk and black slider are supposed to be in the 'locked' position they were when I opened my tank (see annotated photo below) or if the black stalk should go in the slot to allow the black slider to rise further into the top half of the expansion tank.

Reply With Quote
  #4  
Old 12-30-2010, 04:45 PM
Meaux Meaux is offline
SnakeBit...
Location: Foley, Alabama
 
Join Date: Oct 2007
Posts: 77
Mein Auto: 01 530i
I was going to offer you mine, but I can't seem to buy a New one that dosen't leak...

I just noticed the one pictured only has one hose connection... Mine has 2...
__________________


92 Porsche 968
72 Porsche 911T
85 Ford F-150 w/95 302HO
01 BMW 530i
08 Chebby SUV
01 Ford SVT Lightnin'...

Lazy Bum That Lives Off His Wife...

Last edited by Meaux; 12-30-2010 at 04:48 PM.
Reply With Quote
  #5  
Old 12-30-2010, 06:00 PM
bluebee's Avatar
bluebee bluebee is offline
Seek to understand,^Value
Location: San Jose, California
 
Join Date: Mar 2008
Posts: 20,127
Mein Auto: 02 BMW 525i M54 auto 130K
Quote:
Originally Posted by Meaux View Post
one hose connection... Mine has 2...
My Behr OEM expansion tank pictured has two hose connections on the bottom plus one sensor connection.

The top has the main opening plus a nipple.


Last edited by bluebee; 12-30-2010 at 06:14 PM.
Reply With Quote
  #6  
Old 12-30-2010, 08:14 PM
Meaux Meaux is offline
SnakeBit...
Location: Foley, Alabama
 
Join Date: Oct 2007
Posts: 77
Mein Auto: 01 530i
In post#3, I see only One hose connection... Jeeze, you folks will argue about anything...

Christ.
__________________


92 Porsche 968
72 Porsche 911T
85 Ford F-150 w/95 302HO
01 BMW 530i
08 Chebby SUV
01 Ford SVT Lightnin'...

Lazy Bum That Lives Off His Wife...
Reply With Quote
  #7  
Old 12-31-2010, 09:00 PM
bluebee's Avatar
bluebee bluebee is offline
Seek to understand,^Value
Location: San Jose, California
 
Join Date: Mar 2008
Posts: 20,127
Mein Auto: 02 BMW 525i M54 auto 130K
Quote:
Originally Posted by Meaux View Post
you folks will argue about anything...
I'm confused. What are we arguing about?

All I'm asking is for someone to open theirs up and snap a few pictures.


Last edited by bluebee; 02-02-2011 at 11:19 AM.
Reply With Quote
  #8  
Old 01-05-2011, 07:44 PM
bluebee's Avatar
bluebee bluebee is offline
Seek to understand,^Value
Location: San Jose, California
 
Join Date: Mar 2008
Posts: 20,127
Mein Auto: 02 BMW 525i M54 auto 130K
Quote:
Originally Posted by bluebee View Post
All I'm asking is for someone to open theirs up and snap a few pictures.
For the record ...

The "jtwoods5" expansion tank "blew up" yesterday ... so I asked him in this thread to cut it open to snap a picture of the position of the black surge float.
Originally Posted by jtwoods5 ... My expansion tank blew up yesterday

The pike530 expansion tank blew up 12-29-2010 ... so I asked him in this thread to cut it open to snap a picture of the black float position.

Papabear426 is replacing his expansion tank as reported today ... so I asked him in this thread to cut it open and post a picture for us.

Last edited by bluebee; 01-10-2011 at 07:53 PM.
Reply With Quote
  #9  
Old 01-10-2011, 09:36 PM
bluebee's Avatar
bluebee bluebee is offline
Seek to understand,^Value
Location: San Jose, California
 
Join Date: Mar 2008
Posts: 20,127
Mein Auto: 02 BMW 525i M54 auto 130K
Interestingly, today, cn90 over here pointed me to an old thread over here that explained how the (E46) coolant level sensor worked as shown below ...

In post #29, bidman explains:
"I am afraid Critter7r's 13 years in parts and service at 2 BMW dealers did not serve him well on this one. There is no such thing as a heating element in the coolant level sensor. There is no pocket of air for heating or cooling and no readings are taken, it is a simple magnetic float switch that operates around the outside of the tube in which the sensor sits. This is fitted to ALL the E46 models."

Later, in post #32, valvtronicdude explains further:
"The coolant [level] temp sensor is a magnetic switch. if you remove the sensor no coolant comes out right it's a dry sensor. there is a float inside the jug with a magnet in it. when the coolant level is low enough the float sits down over the glass bulb of the sensor and the magnet of the float causes two contacts to touch each other inside the sensor and cause a complete circuit. The instrument cluster sees this complete circuit and then knows the coolant level is low."

The last post gives the switch a name:
"To provide enough warning time for coolant loss, the sensor needs to be located part way up the tank rather than at the bottom of the tank. By the time the sensor contact gets made at the bottom of the tank, all coolant has drained out.

Also for those interested, the proper term for magnetically activated switch/sensor is call a Reed switch/sensor
."

Last edited by bluebee; 01-10-2011 at 09:47 PM.
Reply With Quote
  #10  
Old 02-02-2011, 11:04 AM
bluebee's Avatar
bluebee bluebee is offline
Seek to understand,^Value
Location: San Jose, California
 
Join Date: Mar 2008
Posts: 20,127
Mein Auto: 02 BMW 525i M54 auto 130K
For the record, crs555 just replaced his expansion tank (except he accidentally lost the coolant level sensor) ... so I asked him, in addition to the others listed above (jtwoods5, pike530, papabear426) if he could slice open his old expansion tank (when he finds the missing sensor) to snap a few pictures of the position of the black surge float.
Reply With Quote
  #11  
Old 02-15-2011, 09:01 PM
bluebee's Avatar
bluebee bluebee is offline
Seek to understand,^Value
Location: San Jose, California
 
Join Date: Mar 2008
Posts: 20,127
Mein Auto: 02 BMW 525i M54 auto 130K
Here, for the record, is WHERE I suggest the next person cut the expansion tank open.

Note: So far, NOBODY has done the effort to help the team out; but I'm sure someone finally will.

Reply With Quote
  #12  
Old 02-16-2011, 02:26 PM
Jimmys 530i Jimmys 530i is offline
Officially Welcomed to the 'Fest
Location: Conyers, GA
 
Join Date: Feb 2011
Posts: 811
Mein Auto: 2003 530i
I will be overhauling a cooling system on a customers car on Saturday, and I will be able to post up some pics. I might actually have some laying around, if I do I will post up some pics.
__________________
2004 BMW 330ci Silvergray Sport Package, Cold Package, Xenon Headlamps, Premium Package, 6 Speed Manual, Build Date 9/03

Sold - 2003 325i Sedan Japanrot 5 Speed 8k Xenon Headlamps Build Date 11/02
Reply With Quote
  #13  
Old 02-16-2011, 04:27 PM
bluebee's Avatar
bluebee bluebee is offline
Seek to understand,^Value
Location: San Jose, California
 
Join Date: Mar 2008
Posts: 20,127
Mein Auto: 02 BMW 525i M54 auto 130K
Quote:
Originally Posted by Jimmys 530i View Post
I will be able to post up some pics
Great. Especially if you have a few expansion tanks lying around.

The trick is to cut it horizontally about about where I cut it; then you crack it open; and report back as to the position of the BLACK slider and post assembly.

Note: We're talking the all-black side of the tank, not the white slider with the rod on one end and the level sensor on the other.

Thanks, in advance. For the team.
Reply With Quote
  #14  
Old 02-20-2011, 06:55 PM
Jimmys 530i Jimmys 530i is offline
Officially Welcomed to the 'Fest
Location: Conyers, GA
 
Join Date: Feb 2011
Posts: 811
Mein Auto: 2003 530i
I have the expansion tanks, but my camera isn't working. I will post up some pictures as soon as I get another camera. I have one OEM tank, and one aftermarket Behr tank.
__________________
2004 BMW 330ci Silvergray Sport Package, Cold Package, Xenon Headlamps, Premium Package, 6 Speed Manual, Build Date 9/03

Sold - 2003 325i Sedan Japanrot 5 Speed 8k Xenon Headlamps Build Date 11/02
Reply With Quote
  #15  
Old 02-20-2011, 09:26 PM
bluebee's Avatar
bluebee bluebee is offline
Seek to understand,^Value
Location: San Jose, California
 
Join Date: Mar 2008
Posts: 20,127
Mein Auto: 02 BMW 525i M54 auto 130K
Quote:
Originally Posted by Jimmys 530i View Post
I will post up some pictures
I'm told the OEM is Behr/Heat while the aftermarket is Behr/Hella.

Looking forward to the photographs!

What's important is the normal position of the black slider and the post that goes through (we think) the hole in the slider.

My black slider wasn't sliding; and the post was wedged on TOP of the black slider (i.e., not in the hole we think it belongs in). So that's why it's important to see a few more expansion tanks.

Nobody knows (yet) what this chamber accomplishes, in detail.
Reply With Quote
  #16  
Old 02-24-2011, 05:07 PM
Jimmys 530i Jimmys 530i is offline
Officially Welcomed to the 'Fest
Location: Conyers, GA
 
Join Date: Feb 2011
Posts: 811
Mein Auto: 2003 530i
Ok, just got my camera fixed. Here are the pictures. I noticed that the OEM tank had the float pinned down and had a tab holding it in place as seen in the second picture. What caught my eye was that the Behr made in China did not have the float. I am pretty sure that the float is not supposed to move at all. It is wedged between the plastic rod and the bottom, and a tab holds it in place. When I broke off the stalk and undone the tab, the float just fell out. However, on the aftermarket one, the float was missing, but the plastic rod was still there.
OEM Expansion Tank

Here is a picture of the tab that holds the float in place

Here is another angle on the tab

The aftermarket Behr made in China without the float

A close up

The other half of the aftermarket tank

OEM Tank

Oem Tank

Bottom of OEM Tank, the hole which the float was sitting on
__________________
2004 BMW 330ci Silvergray Sport Package, Cold Package, Xenon Headlamps, Premium Package, 6 Speed Manual, Build Date 9/03

Sold - 2003 325i Sedan Japanrot 5 Speed 8k Xenon Headlamps Build Date 11/02
Reply With Quote
  #17  
Old 02-24-2011, 09:16 PM
bluebee's Avatar
bluebee bluebee is offline
Seek to understand,^Value
Location: San Jose, California
 
Join Date: Mar 2008
Posts: 20,127
Mein Auto: 02 BMW 525i M54 auto 130K
Expansion tank autopsy: Surge chamber & level-sensing chamber detailed

Ooooh. Very nice job!

You're the first person to actually do what they said they would (everyone else just talks - but you took action!). Thanks for doing the second known (to me anyway) Bimmerfest expansion tank autopsy (out of thousands replaced & thrown away).

Your slice down the middle was much neater than mine (what did you use?); and it was in the exact same spot (sparing the thin plastic wall separating the surge chamber from the level-sensing chamber.

Your level-sensing chamber looked almost exactly like mine, with the white float riding on the black stalk. The white float had the same magnetic disc in the center for the electrical level sensor reed switch. And the red bobber glued on one corner of the white float was the same as mine (only my bobber was white).

Interestingly, you too had to break the thin (but razor sharp) plastic bulkhead between the level-sensing chamber and the surge chamber (I cut my hands deeply breaking that plastic!).

Once that thin plastic bulkhead between the two chambers was broken, I was amazed to see that your black float was locked in the SAME POSITION that my black float was locked in.

Apparently this is the natural position of that black float! The black stalk "pins" it down, preventing it, apparently, from moving more than about an inch up from the bottom of the surge tank.

So, I guess I was wrong in assuming that the black float moves up and down that black stalk through that oblong hole in the one corner of the black float.

It's sad, but, even with this new found knowledge, I still can't, for the life of me, figure out HOW that second (surge chamber) chamber actually works.

Can you make sense of what the entire intent of that second surge chamber is and how it actually works?

Attached Thumbnails
Click image for larger version

Name:	bmw_e39_expansion_tank_autopsy_1.jpg
Views:	78
Size:	69.9 KB
ID:	267773   Click image for larger version

Name:	bmw_e39_expansion_tank_autopsy_2.jpg
Views:	74
Size:	62.1 KB
ID:	267774   Click image for larger version

Name:	bmw_e39_expansion_tank_autopsy_3.jpg
Views:	71
Size:	52.5 KB
ID:	267775   Click image for larger version

Name:	bmw_e39_expansion_tank_autopsy_4.jpg
Views:	78
Size:	112.8 KB
ID:	267776   Click image for larger version

Name:	bmw_e39_expansion_tank_autopsy_5.jpg
Views:	70
Size:	104.5 KB
ID:	267777  

Click image for larger version

Name:	bmw_e39_expansion_tank_autopsy_6.jpg
Views:	77
Size:	109.3 KB
ID:	267778   Click image for larger version

Name:	bmw_e39_expansion_tank_autopsy_7.jpg
Views:	71
Size:	92.0 KB
ID:	267779   Click image for larger version

Name:	bmw_e39_expansion_tank_autopsy_8.jpg
Views:	77
Size:	73.8 KB
ID:	267780   Click image for larger version

Name:	bmw_e39_expansion_tank_autopsy_9.jpg
Views:	73
Size:	77.4 KB
ID:	267781   Click image for larger version

Name:	positoin_of_black_float_in_surge_chamber.jpg
Views:	2096
Size:	102.2 KB
ID:	267791  

Reply With Quote
  #18  
Old 02-24-2011, 09:25 PM
bluebee's Avatar
bluebee bluebee is offline
Seek to understand,^Value
Location: San Jose, California
 
Join Date: Mar 2008
Posts: 20,127
Mein Auto: 02 BMW 525i M54 auto 130K
Wait a minute!

I just realized that you cut apart TWO tanks! Is that right?

And, that the black float I'm talking about was in the OEM Behr tank's surge chamber.

But, if I understood you correctly, the Chinese tank didn't even HAVE a black float in the surge chamber.

Is that correct?

Attached Thumbnails
Click image for larger version

Name:	chinese_tank_missing_float.jpg
Views:	1290
Size:	100.9 KB
ID:	267792  
Reply With Quote
  #19  
Old 02-25-2011, 04:07 AM
Jimmys 530i Jimmys 530i is offline
Officially Welcomed to the 'Fest
Location: Conyers, GA
 
Join Date: Feb 2011
Posts: 811
Mein Auto: 2003 530i
I replaced the expansion tank on the same car twice since the original cracked up due to age, and the customer brought in the aftermarket for me to put on. I put it on, and it cracked in a month, right across the side. So, I went ahead and put on an OEM tank. My customer noted that his heat became cooler with the aftermarket tank on, but when I put an OEM tank back on, his heat returned to previous temperatures.

The aftermarket tank caught my attention because it failed early, so I just thought I should cut it open just to see if it was the same as the OEM. I just took a hacksaw and carefully cut exactly where you pointed out. The black float seems to restricts the flow to the last chamber in the tank. Look at the last picture I posted, the port that I focused on was the one that it sits over. In the second to last picture, I took a picture where the float would normally sit, seemingly restricting the port.

I thought it was interesting also that the Chinese tank didn't have the float at all. The long plastic rod was there, and the hole for the tab was there, but the float was not.
__________________
2004 BMW 330ci Silvergray Sport Package, Cold Package, Xenon Headlamps, Premium Package, 6 Speed Manual, Build Date 9/03

Sold - 2003 325i Sedan Japanrot 5 Speed 8k Xenon Headlamps Build Date 11/02

Last edited by Jimmys 530i; 02-25-2011 at 04:08 AM.
Reply With Quote
  #20  
Old 02-25-2011, 05:31 AM
bluebee's Avatar
bluebee bluebee is offline
Seek to understand,^Value
Location: San Jose, California
 
Join Date: Mar 2008
Posts: 20,127
Mein Auto: 02 BMW 525i M54 auto 130K
Quote:
Originally Posted by Jimmys 530i View Post
My customer noted that his heat became cooler with the aftermarket tank on, but when I put an OEM tank back on, his heat returned to previous temperatures.
I don't know HOW that expansion tank second chamber works, but, I remember somewhere (I think it was cn90) someone mentioned that the hoses at the bottom go to the heater core ... so ... maybe ... just maybe ... the lack of that "surge float" is what caused that problem???

Quote:
Originally Posted by Jimmys 530i View Post
In the second to last picture, I took a picture where the float would normally sit, seemingly restricting the port.
I wish I understood how that second chamber, with the float and the two hoses, actually worked!

Quote:
Originally Posted by Jimmys 530i View Post
I thought it was interesting also that the Chinese tank didn't have the float at all. The long plastic rod was there, and the hole for the tab was there, but the float was not.
This IS strange. Why bother with the long plastic rod that goes half way down from the top, if the float isn't there below it? And why have the "tab" if there's no float?

Does it seem like the Chinese tank quality control "missed" the lack of the black float?

PS: You're GOOD with a hack saw!
Reply With Quote
  #21  
Old 02-25-2011, 12:31 PM
Jimmys 530i Jimmys 530i is offline
Officially Welcomed to the 'Fest
Location: Conyers, GA
 
Join Date: Feb 2011
Posts: 811
Mein Auto: 2003 530i
I will watch out for more expansion tanks to chop up and analyze. I happen to have a OEM E46 tank, will that help?
__________________
2004 BMW 330ci Silvergray Sport Package, Cold Package, Xenon Headlamps, Premium Package, 6 Speed Manual, Build Date 9/03

Sold - 2003 325i Sedan Japanrot 5 Speed 8k Xenon Headlamps Build Date 11/02
Reply With Quote
  #22  
Old 02-25-2011, 06:57 PM
bluebee's Avatar
bluebee bluebee is offline
Seek to understand,^Value
Location: San Jose, California
 
Join Date: Mar 2008
Posts: 20,127
Mein Auto: 02 BMW 525i M54 auto 130K
Quote:
Originally Posted by Jimmys 530i View Post
I will watch out for more expansion tanks to chop up and analyze. I happen to have a OEM E46 tank, will that help?
It's always good to see what's different (e.g., that Chinese Behr missing the surge float) so we can figure out what goes wrong with these things!
Reply With Quote
  #23  
Old 02-26-2011, 04:28 AM
Jimmys 530i Jimmys 530i is offline
Officially Welcomed to the 'Fest
Location: Conyers, GA
 
Join Date: Feb 2011
Posts: 811
Mein Auto: 2003 530i
So far, the only reason I have had to replace an expansion tank is when it cracks down the side, and it starts spitting hot coolant all over the engine bay.
It seems that the plastic gets brittle after so many cooling and heating cycles and pressure it just splits because it cannot handle the pressure anymore. Looking back, I just noticed that the Chinese tank had considerably thinner walls compared to the OEM tank, and that is probably the reason why it failed so soon ( 1 month).
I might get another expansion tank today off of a 1999 528i that has over 300k on it, all one owner.
__________________
2004 BMW 330ci Silvergray Sport Package, Cold Package, Xenon Headlamps, Premium Package, 6 Speed Manual, Build Date 9/03

Sold - 2003 325i Sedan Japanrot 5 Speed 8k Xenon Headlamps Build Date 11/02
Reply With Quote
  #24  
Old 07-16-2011, 06:48 PM
bluebee's Avatar
bluebee bluebee is offline
Seek to understand,^Value
Location: San Jose, California
 
Join Date: Mar 2008
Posts: 20,127
Mein Auto: 02 BMW 525i M54 auto 130K
Quote:
Originally Posted by Jimmys 530i View Post
I just noticed that the Chinese tank had considerably thinner walls compared to the OEM tank
Interestingly, today was posted some expansion tank autopsy photos showing extensive damage to the inner thin plastic walls:
- E39 (1997 - 2003) > Coolant Leak - Fixed

Attached Thumbnails
Click image for larger version

Name:	DSC_0020sm.jpg
Views:	1220
Size:	96.7 KB
ID:	285410   Click image for larger version

Name:	DSC_0031sm.jpg
Views:	92
Size:	81.0 KB
ID:	285411   Click image for larger version

Name:	DSC_0033SM.jpg
Views:	83
Size:	71.3 KB
ID:	285412  
Reply With Quote
  #25  
Old 07-16-2011, 07:56 PM
Fudman's Avatar
Fudman Fudman is offline
Officially Welcomed to the 'Fest
Location: Sudbury, MA
 
Join Date: Apr 2007
Posts: 6,130
Mein Auto: '02 530i Sport auto
HOLY CR@P! I just ordered all my parts for a cooling system overhaul (I just turned 89K). And I ordered a Behr expansion tank!!! Now it looks like I need to check to see if any of my parts originated in China, even from reputable brands! And then return those that are. Cr@p!!!!!!
Reply With Quote
Reply

Bookmarks


Forum Navigation
Go Back   Bimmerfest - BMW Forums > BMW Model Discussions > 5 Series > E39 (1997 - 2003)
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 02:51 AM.


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