E46 BMW Social Directory E46 FAQ 3-Series Discussion Forums BMW Photo Gallery BMW 3-Series Technical Information E46 Fanatics - The Ultimate BMW Resource BMW Vendors General E46 Forum The Tire Rack's Tire Wheel Forum Forced Induction Forum The Off-Topic The E46 BMW Showroom For Sale, For Trade or Wanting to Buy

Welcome to the E46Fanatics forums. E46Fanatics is the premiere website for BMW 3 series owners around the world with interactive forums, a geographical enthusiast directory, photo galleries, and technical information for BMW enthusiasts.

You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. By joining our free community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join our community today!

If you have any problems with the registration process or your account login, please contact contact us.

Go Back   E46Fanatics > Tuning & Tech > DIY: Do It Yourself

DIY: Do It Yourself
Post here to share or improve your wrench turning skills! All BMW E46 DIY tips, tales, and projects discussed inside. Learn to work on your car and know the right BMW parts you will need!

Reply
 
Thread Tools Search this Thread Rating: Thread Rating: 10 votes, 5.00 average. Display Modes
Old 10-09-2011, 04:17 PM   #1
delmarco
Registered User
 
Join Date: Nov 2008
Location: Westchester, NY
Posts: 6,287
My Ride: 2001 330i
Send a message via ICQ to delmarco Send a message via Yahoo to delmarco
Cool DIY Guide: Coolant System! Bleeding, Leaks, Hoses & Expansion Tank Explained!

DIY GUIDE

SOLUTION TO COOLANT SYSTEM OVERHAUL, BLEEDING OUT AIR AND TROUBLESHOOTING SIMPLE E46 M54 COOLANT ISSUES!


I just completed my coolant overhaul successfully following the infamous 330ci.net DIY.

http://www.bmw330ci.net/maintenance/completecoolant.php

His DIY was on point and should be followed by those attempting to do this easy project.

There was however a few exceptions I came across that should be addressed for sake of clarity.

Also everyone that attempts this project comes across the same post-DIY issues regarding bleeding and leakage. I will clarify this below.

PART ONE: BASIC E46 M54 COOLANT OVERHAUL - Replacing Expansion Tank, Upper and Lower Hoses, Sensors, And what you need to know before attempting to do so.


1.
The word BLEED is used so many times it gets confusing. When you begin the DIY you will DRAIN OUT coolant from one or two drain sites. These are the blue Radiator/Expansion Tank drain screw(s) or the Engine Block drain plug bolt. When you drain coolant from one site or both air WILL enter the system.

When you refill coolant you DO NOT want air to still be in the system so you will have to BLEED OUT Air (force it out by flooding the cooling system with coolant and letting gravity do the work as air is lighter and rise up will bubble out) as you REFILL the coolant. This technique will be discussed later on. But it is important to understand that whenever you drain out coolant (even if it is a little spoonful) from one or both of the drain sites you MUST BLEED OUT air from the system as you refill the coolant.

2. You do not have to drain the entire coolant system to change the Upper and Lower (U/L) hoses, Expansion Tank (ET), Thermostat, Water Pump (WP). For the general Coolant Overhaul DIY you can only drain the radiator/ET blue drain screw(s). This will evacuate coolant out of most areas that you are overhauling.

That said, when you are done with the overhaul and are refilling coolant into the system you STILL NEED to properly bleed the air out of system the same way as if you had drained the entire system.

3. There is a huge structural difference between the Coolant System of the E46 M54 Automatic/Steptronic and Manual/Standard cars.

-Manual cars have two blue color drain screws below the radiator/ET area whereas automatic cars have only one which is attached to the Radiator.

-There is the obvious distinction between the fans but I will reiterate.

Manual cars have one electric fan. For the Coolant system overhaul this fan needs to be removed. It sits inside the engine bay but is not attached to the engine block. It plugs into a wire harness connector and attaches to the inside brace of the radiator support.

Automatic cars have two fans: one small auxiliary-electric fan that is outside the engine bay behind the bumper-grill area and one large mechanical fan that sits on the front of the engine block inside the engine bay. This mechanical fan is the one that needs to be removed via the special fan tools in order to access the belts, water pump, pulleys, thermostat, and to create space that will allow you to remove the hoses and expansion tank.



4. The removal of the Upper hose is easy and should be done before attempting to remove the Expansion Tank (ET). With the Radiator drained and ET drained on a cold engine the U/L hoses are empty. The only hose that will have a good amount of still warm/hot coolant is the smaller heater hose that runs into the lower half of the ET. Even with the ET/Radiator drained this heater hose will spill out some coolant.

5. Removal of the Expansion Tank is not hard at all. It is only tricky. The 330ci.net write up says to hammer it out from underneath, someone else said to pull up from above. Either way it takes some force to remove it but the thing is the ET is attached to the radiator via a relatively frail plastic bracket that most likely did not come with your overhaul kit and would need to be ordered seperately if you break it.

What worked for me: I took a simple portable Sears Hydraulic Jack (even the OEM jack will work) and placed a socket extension (or a sturdy socket screw driver will work) between the jack's pad and the bottom of the ET and slowly jacked it up. This took a few seconds and worked because the force from the jack is only directed and centered on the coolant tank.

Surprisingly there was still a lot of coolant in the ET when it popped out of it's radiator support socket so I was glad to not be under there hammering the thing up from below.

6. ALWAYS REPLACE YOUR EXPANSION TANK'S CAP! The old Expansion Tank cap may still look new but it is not! On the neck of cap are two hard to see rubber seals that seal in and regulate pressure inside the tank. I believe the seals get imprinted onto the neck of the old tank overtime and deform to work only with that tank. When the tank is replaced and the old cap is used on a new tank it will not work properly since the seals on the old cap are, for lack of a better word, used up already.



When I applied the old cap onto the new tank it felt "loose" and "gritty" on the tank as it screwed down.



7. Removal of the Lower Hose at the Radiator junction was indeed the toughest part. I found that with the sensor removed and using a long narrow sturdy steel pipe I was able to fit the tip of the pipe in thru the sensor's hole and leverage the hose off the radiator connection using the top metal edge of the radiator support frame to pry it lose. This helped a lot. When you are replacing the lower hose make sure you replace the sensor. It doesn't come with a lot of the general overhaul kits so be sure to buy one.

The green seal ring wears out even if it doesn't look like it.

In the picture below you can see how the old sensor's green seal ring was worn flat and wasn't going to be working anymore!




8. When replacing the coolant it is important to BLEED air out of the system. I'm not an expert but I will write here what worked for me.

PART TWO: BLEEDING OUT AIR FROM THE COOLANT SYSTEM DURING COOLANT REFILL:

a. Our driveway, like most American driveways, at my parent's house is on a slight incline. I just parked the car with the front on the upper most part of the incline so it was elevated. This allowed me to not fuss with a jack to jack up the front of the car. You can choose to jack up your car but 5 inches max for the front tires to be off the ground is all you need.

b. I turned on the car (not the engine just the car) and set the TEMP to 91 with fan speed low.

c. I returned to the ET, removed the cap and screw open the upper hose's black colored bleeder screw midway(it may also be brass or metal).

d. I proceeded to pour a 50/50 mixture of BMW Coolant/Distilled water into the ET until it filled up to the brim and kept pouring until it was overflowing and stopped. When the coolant level went down inside the ET I kept pouring some more coolant mixture in pausing each time it began overflowing.

At some point as the ET repeatedly gets filled to the brim a trickle coolant will begin to exit from the bleeder screw.

e. When that happens stop pouring coolant and close the bleeder screw. Depending on how much air was in the system before you began bleeding it out and the current amount of coolant in the system the coolant level in the ET may or may not subside down to with in the factory's specification level range. Every case will be different here and this is where you have to stop reading what I am telling you determine what your situation is and use your common sense.

- If the level indicator is high and the coolant level in the ET hasn't subsided then you can use a turkey baster and suck some coolant out until it is in with in the normal level. Drive the car around until engine is warm and check the level again

- If the coolant level in the ET subsides below the spec level then add some more coolant in to get it level. Drive the car around and check the level again.

d. If you had drained the entire coolant system at both the radiator and engine block drain sites then after you bleed the system during the refill procedure it may become obvious that you did not pour back in as much coolant as you drained out the system yet your ET is still filled with coolant.

You need to close the ET cap and bleeder screw, start the engine (and/or drive around some) until the engine is warm. Then park the car, turn the engine off, let the engine cool and open the ET cap to see where the level is.

It most likely may be low so keep adding coolant until you have replaced all the original coolant that was initially drained from the system.


That is it.

It is a simple procedure that is easy to get wrong because each car and each project will have it's own unique situation concerning the amount or air that was in the system before bleeding versus the amount of coolant in the system after bleeding. The value of these two variables are tricky to pinpoint without fancy lab equipment so bleeding becomes sort of a guessing game that is based on obersvation (keep looking at the bleeder screw) and using common sense to understand what to do in your unique situation.

There are lots of other ways to refill coolant whiles bleeding air out but this was the most simple way that worked 100% for me.


TROUBLE SHOOT:
If you drive immediately after the overhaul and find that -

A. The Climate Control Heat is not hot or working - There is still air in the system and the system needs to be re-bled to evacuate air. Also check to see that you reconnected the heater hose to the ET correctly.

B. The temp needle fluctuates wildly between the normal temp and the red -
There is air in the system. The funny thing here is the engine is actually not overheating but as pockets of hot air passes thru the lower hose and across the surface area of the temp sensor as coolant flows from the hose into the radiator it creates the impression on the sensor that the engine is running hot and the needle goes towards the red. Also having coolant leaking at the sensor location due to reusing an old sensor with worn out seals may cause this issue.

C. Coolant is Leaking at the Lower Hose/Radiator Junction - Most likely the sensor needs to be replaced.



D. Coolant Leaking at ET - Coolant Level Sensor needs to be replace.



E. Coolant Leaking at Center of Car Directly under engine or towards driver's side of engine bay - One of the other least popular and hard to get to coolant hoses are leaking. There get old and can leak although rarely. Also check the Engine Drain Plug to make sure you replace the crush washer and bolted it back on correctly.


More information will be added soon...
__________________




VISIT MY GARAGE TO SEE ALL MY MODS:

http://directory.e46fanatics.com/use...rMod&UcId=7917

Last edited by delmarco; 10-09-2011 at 09:18 PM.
delmarco is offline   Reply With Quote
Ads by Google

Guests, get your FREE E46Fanatics.com membership to remove this ad.
Old 10-09-2011, 06:00 PM   #2
dmax
Registered User
 
dmax's Avatar
 
Join Date: Aug 2006
Location: NJ
Posts: 22,774
My Ride: '99 328i 1.04646 mu
Nice, Olaf! I'm going to have to study this and learn about cooling stuff!

Oh, tiny note: the 'intake air temp sensor 0-ring' fits the temp sensor on the lower hose of the radiator...so if someone wants to save $10 or so and not buy a new sensor, that's the 0-ring to get.
__________________


Performing at the Comedy Cove--595 Morris Ave. Springfield NJ reservations 973 376-3840

A recent set

dmax on the radio every Wednesday 7-9 p.m. NYC time. Call in! (661) 449-9340 watsonnwatson.com
dmax is offline   Reply With Quote
Old 10-09-2011, 08:27 PM   #3
Solidjake
Zero. Oil. Leaks.
 
Solidjake's Avatar
 
Join Date: May 2008
Location: NYC
Posts: 22,211
My Ride: 2002 330i
First part should be DRAIN the coolant and BLEED the air.
Solidjake is offline   Reply With Quote
Old 10-09-2011, 09:18 PM   #4
delmarco
Registered User
 
Join Date: Nov 2008
Location: Westchester, NY
Posts: 6,287
My Ride: 2001 330i
Send a message via ICQ to delmarco Send a message via Yahoo to delmarco
Quote:
Originally Posted by Solidjake View Post
First part should be DRAIN the coolant and BLEED the air.
fixed.
__________________




VISIT MY GARAGE TO SEE ALL MY MODS:

http://directory.e46fanatics.com/use...rMod&UcId=7917
delmarco is offline   Reply With Quote
Old 11-03-2011, 07:40 AM   #5
LeMansteve
Registered User
 
Join Date: Nov 2008
Location: USA - GA
Posts: 1,629
My Ride: '04 330i 6mt ZSP ZPP
What's the troubleshooting advice if I installed a new ET and new ET cap, but over a few months coolant slowly leaks past the ET cap?
__________________
BMW CCA member - Peachtree Chapter
LeMansteve is online now   Reply With Quote
Old 11-03-2011, 07:51 AM   #6
bwallace530
Registered User
 
Join Date: Jan 2011
Location: Oregon
Posts: 1,866
My Ride: 325
Thanks only read a few paragraphs sense I'm at work but I will be doing this as soon as my parts arrive.

Sent from my PC36100 using Bimmer
bwallace530 is offline   Reply With Quote
Old 11-03-2011, 01:44 PM   #7
xplodngKeys
Registered User
 
Join Date: Jul 2009
Location: Vancouver Canada
Posts: 117
My Ride: '99 323i - RIP 328
Quote:
Originally Posted by LeMansteve View Post
What's the troubleshooting advice if I installed a new ET and new ET cap, but over a few months coolant slowly leaks past the ET cap?
I'd check the o-ring on the cap.... and make sure you clean up your engine bay from all the dirt and oil and other muck so it is easy to spot and trace leaks! (not sure if you have a clean bay or not but if you do... )
xplodngKeys is offline   Reply With Quote
Old 11-03-2011, 03:23 PM   #8
bmwmen
Registered User
 
Join Date: Jul 2011
Location: Netherlands
Posts: 54
My Ride: E46 323Ci
i don't know you personally, but have to say that all of your DIY documents (yes, i have read them all!) are really really nice. Thanks a lot for this amount of knowledge!
bmwmen is offline   Reply With Quote
Old 11-06-2011, 07:44 PM   #9
jbehr99
Registered User
 
Join Date: Aug 2011
Location: Metro Detroit, MI
Posts: 110
My Ride: 2005 330CI Vert ZHP
Hello, I have a 2005 330ci vert with automatic, today I tried to flush the coolant system but could only get out the coolant from the radiator and not the expansion tank. I do not have another drain plug besides the one under the expansion tank and I am confused on how to drain the expansion tank? If I could get some insight into how to drain the expansion tank that would be great.
Thanks
jbehr99 is offline   Reply With Quote
Old 11-08-2011, 02:24 AM   #10
dan_1337
Registered User
 
Join Date: Apr 2010
Location: Melbourne, Australia
Posts: 533
My Ride: 330CiC
All good advice and I completed the DIY around two months ago. Only thing different in the DIY was that I found that in step 43 my bolt was actually an 8mm hex and not a T50 torx. I found that removing the expansion tank (ET) was one of the hardest parts (same difficulty as the lower radiator hose) and found that it helped to ask someone to pull from the top while I pushed from the bottom - before getting a face full of coolant from whatever was left in the ET.

I also made a pdf version of the http://www.bmw330ci.net/maintenance/completecoolant.php DIY so I had big pictures to quickly refer to while under my car (8.5mb):
http://dl.dropbox.com/u/11284289/Coo...20Overhaul.pdf

Unfortunately a leak has sprung above the ET and I cannot seem to find where it could be coming from for the life of me. The top ridge of my ET is a little wet with coolant, but when I reach my fingers under the two hoses above the ET (hose to ET and hose to radiator) I can't feel any wet coolant. It's also not coming from the bleed valve on top of my upper radiator hose as there are no coolant stains there.

Do you have any ideas on where or why I might be getting coolant wetness around the top of my ET? When I first found it, there was so much coolant that there was a small puddle that splashed through my splash guard! Now it's more like what the pictures look like:



__________________

Last edited by dan_1337; 11-08-2011 at 02:42 AM.
dan_1337 is offline   Reply With Quote
Old 11-14-2011, 10:10 AM   #11
STORMER
Registered User
 
Join Date: Sep 2009
Location: Canada
Posts: 1,055
My Ride: AA SC 98 M3
Also would like to point out that I just did this over the weekend on my 99 323i(complete cooling overhaul incl. radiator) and i actually had only one bleed screw under the et and had two fans! one electric and one mechanical?! And yes my car is a standard, always has been??? Anybody else run into this?

Happy to say the diy was still very succussful thanks to above info and links


Sent from my iPhone using BimmerApp
__________________


360+rwhp

AA Stage 2, Arp2000, Underdrive Pulley, M50 Manifold, Cat Delete, Supersprint Exhaust, M5 Clutch w/ Lightweight Flywheel, Euro Fan, FK Coilovers, AEM Boost Gauge, Zhp Knob, Stoptech Brakes, R1 Rotors

Quote:
Originally Posted by Sweetness View Post
You sir, just thread jacked the sh!t out of OP.
STORMER is offline   Reply With Quote
Old 11-21-2011, 09:51 PM   #12
aleksankazakov
Registered User
 
Join Date: Mar 2011
Location: U.S.A
Posts: 234
My Ride: 04 E46 330i sport
I just finished my DIY and I didnt remove the expansion tank, I had to take the whole assembly out because the tank would not come out. Then I hammered it off the plastic assembly . The AT thermostat broke off just as i expected. Plastic on that assembly and on the thermostat reminded me chocolate. It was crumbling easy with fingers. So now I replaced, the hoses, the expansion tank, the AT thermostat, the main thermostat and the assembly. Total part's cost exceeded 500 USD. I used prestone golden coolant . Everything mounted plug and play easily. My advice is not to remove old tank and just buy the assembly and the AT thermostat and put the new tank on the new assembly. Easier this way.
aleksankazakov is offline   Reply With Quote
Old 11-21-2011, 11:13 PM   #13
B33MER
Registered User
 
Join Date: Sep 2008
Location: SJ, Malaysia
Posts: 1,103
My Ride: 330i SMG M-Sport
Great write-up Thanks for sharing!
__________________
330i SMG M-Sport Paket II Euro Spec
Mods:
CF Roundels all around, Black grillz, 7000k Angel eyes,6300k HID fog lights, Hamman Lip reps, ACS roof spoiler reps, Alutech front and rear struts, BMC CDA with DIY heatshield, Pro RS braided brake line, ///M Billet Oil Cap, OEM ///M mats, ///M aluminium pedals,

B33MER is offline   Reply With Quote
Old 12-02-2011, 12:27 PM   #14
TeamBMW
Registered User
 
Join Date: Oct 2011
Location: North Jersey
Posts: 11
My Ride: 2000 328i Sedan
awesome DIY
TeamBMW is offline   Reply With Quote
Old 02-07-2012, 04:00 PM   #15
AdrianE46
Registered User
 
Join Date: Jan 2012
Location: wappingers
Posts: 41
My Ride: 2000 323i
Question?? i live in New York and the weather right now will not allow for me to work on my car also don't have a garage. How long could i get away with my driving with the ET leak ???
AdrianE46 is offline   Reply With Quote
Old 02-07-2012, 10:45 PM   #16
Bmw_fever
Registered User
 
Join Date: Oct 2010
Location: Canada
Posts: 212
My Ride: 01' 325i ZSP ZCW
I presume that I can follow this DIY on my 2001 325i? or are their differences?
Bmw_fever is offline   Reply With Quote
Old 02-08-2012, 01:24 PM   #17
STORMER
Registered User
 
Join Date: Sep 2009
Location: Canada
Posts: 1,055
My Ride: AA SC 98 M3
Quote:
Originally Posted by Bmw_fever View Post
I presume that I can follow this DIY on my 2001 325i? or are their differences?
U should be just fine
Only real difference is if you have an automatic where you would have to remove a mechanical fan thats about it!


Killing time at work using BimmerApp
__________________


360+rwhp

AA Stage 2, Arp2000, Underdrive Pulley, M50 Manifold, Cat Delete, Supersprint Exhaust, M5 Clutch w/ Lightweight Flywheel, Euro Fan, FK Coilovers, AEM Boost Gauge, Zhp Knob, Stoptech Brakes, R1 Rotors

Quote:
Originally Posted by Sweetness View Post
You sir, just thread jacked the sh!t out of OP.
STORMER is offline   Reply With Quote
Old 03-06-2012, 03:40 PM   #18
330charlie
Registered User
 
Join Date: Aug 2011
Location: SW Ohio
Posts: 10
My Ride: 330i
I love you DIY guys. Just replaced my cracked ET today for around $100 worth of parts. The BMW CCA parts discount at the dealer makes membership totally worth it. So far so good and saved $340.00 compared to the dealer quote!
__________________
330charlie is offline   Reply With Quote
Old 12-09-2012, 06:24 PM   #19
nzvlnr
Registered User
 
Join Date: Dec 2011
Location: CALIFORNIA
Posts: 16
My Ride: 2005 325i
How the FREKKKKKKKKKKKKKKKKKK....do you get the heater hose back on!@#%&*!! The one that is on the back of the engine block. I got the old one off, but I cannot get the new one and I am a tad stressed. It just doesnt want to slip on so I can slide the clips down, I lubed it up with a little coolant and...it..........just.........wont ............go!!!!!! Any ideas?
nzvlnr is offline   Reply With Quote
Old 12-15-2012, 11:00 AM   #20
nzvlnr
Registered User
 
Join Date: Dec 2011
Location: CALIFORNIA
Posts: 16
My Ride: 2005 325i
How the FREKKKKKKKKKKKKKKKKKK....do you get the heater hose back on!@#%&*!! The one that is on the back of the engine block. I got the old one off, but I cannot get the new one and I am a tad stressed. It just doesnt want to slip on so I can slide the clips down, I lubed it up with a little coolant and...it..........just.........wont ............go!!!!!! Any ideas?
nzvlnr is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

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
Censor is ON





All times are GMT -5. The time now is 11:26 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
(c) 1999 - 2011 performanceIX Inc - privacy policy - terms of use