[txusa03]

I have been studying this thread 3-4 times now, reading it over and over again and trying to picture myself fiddling under the car. I am also using JamesUKE92 thread to help me picture and identify these parts before getting my feet (or face in this case) wet .

I am seeing lot of hoses under the car and afraid to remove the wrong one. So if I understand this, to drain the coolant from the engine block, you just need to remove one of the end of the hose that connect to the water pump (no need to remove both end) correct? You also confirmed that no coolant was found when you removed the hose from the block to the water pump right?

Also I borrow JamesUKE92 photo of the water pump. Which opening is connected to the engine block (1 or 2)? I am sure it might be easy to identify once I craw under there. Thanks ENINTY and James both for your contribution.

[robmoe]

So I need to replace my theromstat according to my check engine light. While I am changing the coolant I was planing to do this at the same time. Can anyone help explain where the thermostat assembly is located on the e90 and what it looks like.

Thanks!

[txusa03]

Originally Posted by robmoe

So I need to replace my theromstat according to my check engine light. While I am changing the coolant I was planing to do this at the same time. Can anyone help explain where the thermostat assembly is located on the e90 and what it looks like.

Thanks!

The power of e90post...http://www.e90post.com/forums/showthread.php?t=347412

[cgnahc]

how long does this take?

[ENINTY]

Originally Posted by cgnahc

how long does this take?

Set aside 3 hours for your first time with it.

[zakkthebear]

I just want to say thank you for the awesome write up. A friend and I banged it out in today in about 80 minutes and every step was spot on. There was no guess work, we just went #1 to the end.

Thank you for this great resource that you shared with all of us. A big for this thread!

[Chriztofor]

Well 2 dealers didn't have the drain plugs, so one of them sold me 2 "control sleeves" which contain the plugs. http://www.koperformance.com/online_...-17117521781-9

At 57,000 miles I was just going to change the drain plugs, but I decided to change the sleeves too. Well I am not touching that anymore. I was sweating it out. To get them out you turn 1/4 of a turn (counterclockwise) and you pull straight down. After removing them, I noticed that the tabs on the old control sleeves broke off! I was nervous because I didn't want to break the radiator. Well the new sleeves went back in smoothly, but in the future I am staying away from those sleeves. Now, the reason why I changed them in the first place is that both sleeves have 2 rubber O-rings on them. What do they do I have no clue, but it must seal something and after 57,000 miles who knows if those rubber o-rings are any good. They "looked" alright. I will not touch that again until 150,000 miles. Whew.

By the way, great write-up.

[uno]

Thanks a lot for the detailed write up. I finally did mine.

Drained engine block, Bled three times, added little after bleeding, total used about 1.5 gallon.
The manual said the capacity is 2 gallon. Don't know where 0.5 gallon goes.

[allmotorh22]

Q: if only 16oz of fluid comes out of the engine block part (the amount thats in a regular bottle of drinking water), is it really necessary to do this part?

can you see/check the condition of the water pump impeller or thermostat if you do this portion of it?

[bumere90]

do you guys now if I can mix the coolant with distiled water? because I heard that it is not a good idea because the engine block is made from magnesium which will/can react with water and burn the block..is this true? what other solvents can I use?

[bmwpk]

Originally Posted by bumere90

do you guys now if I can mix the coolant with distiled water? because I heard that it is not a good idea because the engine block is made from magnesium which will/can react with water and burn the block..is this true? what other solvents can I use?

water is fine. never heard of that.

[Casca]

Originally Posted by bumere90

do you guys now if I can mix the coolant with distiled water? because I heard that it is not a good idea because the engine block is made from magnesium which will/can react with water and burn the block..is this true? what other solvents can I use?

They use magnesium for flares that are activated by salt water...the important thing being salt. Toss those flares in a fresh water lake and they will probably not ignite. If we were flying over fresh water, I'd have to sprinkle in some salt and then throw em out. The magnesium in the flare is powdered and easy to ignite with ...salt and water. A magnesium block is not in powder form....it is a block. The only kinda solid magnesium part that could potentially ingnite were brakes on some aircrafts and that only happens in extreme conditions that a BMW engine block will never approach. And yeah, spraying water on a magnesium brake (or flare) fire will probably make it explode.

Also, I'd guess the largest amount of anything even in concentrated coolant is water.

[Chriztofor]

Originally Posted by bumere90

do you guys now if I can mix the coolant with distiled water? because I heard that it is not a good idea because the engine block is made from magnesium which will/can react with water and burn the block..is this true? what other solvents can I use?

You have to mix the coolant with distilled water. DO NOT USE TAP WATER. Tap water contains minerals and other solids that will cake inside your system (Ask me how I know ) By the way, you can not use straight anti-freeze because as member John070 said, antifreeze also helps the coolant from boiling.

[bumere90]

thanks for clarifying guys!!

[txusa03]

FWIW, I did not take out the pipe for the engine block. Too much work under tight space for coolant. I would have done it had I had a lift.
However, while under the car, I opened the drain plug on the driver side. Got all the coolant out from that drain. Then I decided to opened the drain plug on the passenger side and got more coolant out (half a bottle of 16 fl oz) from that side. I just wanted to let everyone know that I got more coolant when I removed both plugs.

Again, thanks to OP for his great contribution!

[ENINTY]

So I was wondering about the two radiator drains. I could have sworn my car only had a radiator drain on the left-side. Today I replaced my thermostat and now I am positively sure MY car (April 2006-build) has only one radiator drain and it is on the left-side (driver's side). Just wanted to clarify.

[blingman]

so I followed this procedure:

"17) Insert the key into the dash slot and hit the starter button (but don’t start the engine – e.g. keep your foot off the bake/clutch).
18) When the ignition is on, set the heater to the highest temp (84 deg.) and set the fan on low.
19) Hold down the accelerator pedal for 10 seconds then release. This activates the water pump and it will cycle for about 12 minutes to vent all the trapped air into the coolant reservoir (it sounds like a min washing machine). Don’t open the reservoir cap or bleed screw during the venting process! (you’ll have start the process over) You may want to hook up a extra battery to the under-hood jumper points to keep the car’s battery from running down."

but the water pump did not activate. tried it couple times and still nothing.

key in, foot off brake, hit start button, fan low, heat at high, foot on gas pedal down for 10 seconds and release. nothing happen :/

am i missing something? my car is 2006 325i if that makes any difference

[txusa03]

Originally Posted by ENINTY

So I was wondering about the two radiator drains. I could have sworn my car only had a radiator drain on the left-side. Today I replaced my thermostat and now I am positively sure MY car (April 2006-build) has only one radiator drain and it is on the left-side (driver's side). Just wanted to clarify.

I have 2. I have the very early e90 (built date April 05). Look at number 3.

[AlanAZ]

am i missing something? my car is 2006 325i if that makes any difference

Worked on my 06 325i. 3x, see entry on page 1.

[mag12000x]

Originally Posted by blingman

so I followed this procedure:

"17) Insert the key into the dash slot and hit the starter button (but don’t start the engine – e.g. keep your foot off the bake/clutch).
18) When the ignition is on, set the heater to the highest temp (84 deg.) and set the fan on low.
19) Hold down the accelerator pedal for 10 seconds then release. This activates the water pump and it will cycle for about 12 minutes to vent all the trapped air into the coolant reservoir (it sounds like a min washing machine). Don’t open the reservoir cap or bleed screw during the venting process! (you’ll have start the process over) You may want to hook up a extra battery to the under-hood jumper points to keep the car’s battery from running down."

but the water pump did not activate. tried it couple times and still nothing.

key in, foot off brake, hit start button, fan low, heat at high, foot on gas pedal down for 10 seconds and release. nothing happen :/

am i missing something? my car is 2006 325i if that makes any difference

Suggest when you try this, you check underneath by listening to the pump close-up to see if it's actually running or not. It's pretty quite in operation.

[acdHQK713K]

What does the actual venting procedure do?

Should the bleed screw be open while the pump is in the venting mode and running?

I changed my coolant out and have run the venting procedure twice now, but my temps seem to be slightly higher than I recall before I did the flush.

[mag12000x]

"What does the actual venting procedure do?"

Venting or "Bleeding" (Bentley Manual) is the system designed in the E9X to flush out any trapped air in the engine cooling system. Without it, you can cause damage to the engine by allowing it to run and creating "hot spots".

"Should the bleed screw be open while the pump is in the venting mode and running?"

No, the bleed screw should be opened for refilling purpose only, closed during 12minute bleeding cycle.

"I changed my coolant out and have run the venting procedure twice now, but my temps seem to be slightly higher than I recall before I did the flush."

What car do you have?, How are you checking your temperature? The E90 330i doesn't come with a temp gauge....