CREDIT TO ORIGINAL AUTHOR TRACK-CZAR. This is from the cached version of m3forums which is rapidly disappearing.
"Like many others, I have been searching for a comprehensive DIY that covers the coolant flush procedure required for the Inspection II service. Without a definitive DIY, I left this as my last item. Despite finding the various dead links in the forum and the considerable discussion over the difficulty of removing the lower radiator hose, I nonetheless moved forward, taking pictures along the way, in hopes of creating a single DIY for others to follow.
I am pleased to report that this procedure was much easier than I imagined and I believe I have found a way to perform a complete flush without removing the lower radiator hose.
EDIT: Thanks goes to Function7 for posting his pictures on another thread and providing some basic information that helped me get through this.
So here goes:
1. Place the car on jacks or ramps. (Search the forum for various methods on this)
2. Then remove the front splash shield. Mine had 6 bolts holding it on. Nothing difficult here. It just comes right out.
3.Up top, remove the 4 plastic retainers for the air inlet piping.
4. Use either dykes or a thin flat screwdriver to pull up on the center pin, then remove the entire retainer.
5.Here is the piece out with the 4 retainers:
6. Next remove the intermediate duct elbow. No screws or retainers here.
7. Just pull straight up
8. Now you can see the bleed valve on the upper radiator, more on that later:
9. Next, we need to remove the passenger side fan shroud. There are 2 retainers holding this piece in and they are slightly larger than the first 4 holding th air duct. The first one is dead center on top.
10. The second is down on the passenger side:
11. Once the 2 retainers are out, this piece pulls straight up. Note the tab on the bottom...when replacing this piece later, be sure to put that back in its correct holder (easy to see)
12. Now if you look down, you can easily see the lower coolant hose. An electrical connection is hooked to the top of the hose for the temp sending unit.
13. Pinch the metal wire and remove the connector.
14. Electrical connection removed
15. Here is where one would normally try to remove the lower hose (after pulling up on the wire clip). But, I noticed that the temp sending unit was easily removable. So, I pulled out an old concrete mixing tub (Home Depot - $10 a few years ago)
16. Placed it under the car next to the passenger ramp
17. Carefully loosened the overflow tank cap (my car was still hot so I used a rag)
18. Using a standard flat blade screwdriver, unscrew the bleed valve in the upper radiator hose.
19. Then, once the pressure has been released, using a sizeable rag as a shield, remove the temp sending unit by pressing in each of the side tabs and pulling up. It should come right out. Keep the rag their until the pressure is low enough.
20. I had a considerable amount of fluid drain out. I caught about 98% of it.
21. At this point, I started to blow air down the overflow cap using a paper towel over the opening. Blue fluid definitely came out. (Sorry, not going to show action pics of this stage)
22. After several minutes of this, I decided to switch to my shop vac. Before placing it on the overflow tank, I ran it for 30 seconds or so to get out all of the dust (I would recommend cleaning your vac if its bad...I may have had a few bits of dust fly into the overflow reservoir). It was unbeliveable how much came out. Just make sure your on "blow" and not "suck".
23. Overall, this method resulted in 1.5 gallons of fluid.
24. Finally, need to get to the block drain bolt. Under the car, look up at the passenger side of the block. You will see a cannister (some say it is for the VANOS). Remove the (EDIT) 10mm bolt and spacer.
25. Spread open the hinged tabs and push the canister up and to the right. You can now easily see the block drain bolt.
26. Using a series of extensions and a universal joint on a 3/8 ratchet, I was able to break this 13mm bolt loose. Like others have said...this can be messy. I had a large rag between me and block. Once loose, the bolt fell into the pan. Mostly, my arm was drenched. The pan caught another 1/2 gallon. I have read to replace the aluminum bushing on the bolt, but I just flipped it over and reused it.
27.From here it was easy....replace the block drain bolt and the VANOS cannister.
28. Replace the temp sending unit and the electrical connector
29. Mix up a gallon of BMW coolant (blue) with a gallon of distilled water ($.85 at the local grocery store)
30. Find a funnel (I cut the distilled water jug and used it and a buddy to hold it) and pour the 50/50 mix into the reservoir. Mine took the whole 2 gallons.
31. Turn the car on and the heater on full blast.
32. Reinstall the bleed valve, but leave it barely cracked open.
33. My coolant tank was low and the yellow coolant warning light was on, so I had to add another 1/2 gallon of water to the system.
34. Run the car for a while and watch the temp guage....any sign of high temps....shut her down!
35. I opened and closed the bleed valve a few times. Ultimately, I stopped seeing fluid come out.
36. Reinstall the fan shroud and the 2 air duct pieces.
37. Reinstall the undertray (I left mine off for a couple of days to watch for leaks)
38. With all of the fluid spray that occured....I gave the engine bay a quick hose down."
__________________
"Like many others, I have been searching for a comprehensive DIY that covers the coolant flush procedure required for the Inspection II service. Without a definitive DIY, I left this as my last item. Despite finding the various dead links in the forum and the considerable discussion over the difficulty of removing the lower radiator hose, I nonetheless moved forward, taking pictures along the way, in hopes of creating a single DIY for others to follow.
I am pleased to report that this procedure was much easier than I imagined and I believe I have found a way to perform a complete flush without removing the lower radiator hose.
EDIT: Thanks goes to Function7 for posting his pictures on another thread and providing some basic information that helped me get through this.
So here goes:
1. Place the car on jacks or ramps. (Search the forum for various methods on this)
2. Then remove the front splash shield. Mine had 6 bolts holding it on. Nothing difficult here. It just comes right out.
3.Up top, remove the 4 plastic retainers for the air inlet piping.
4. Use either dykes or a thin flat screwdriver to pull up on the center pin, then remove the entire retainer.
5.Here is the piece out with the 4 retainers:
6. Next remove the intermediate duct elbow. No screws or retainers here.
7. Just pull straight up
8. Now you can see the bleed valve on the upper radiator, more on that later:
9. Next, we need to remove the passenger side fan shroud. There are 2 retainers holding this piece in and they are slightly larger than the first 4 holding th air duct. The first one is dead center on top.
10. The second is down on the passenger side:
11. Once the 2 retainers are out, this piece pulls straight up. Note the tab on the bottom...when replacing this piece later, be sure to put that back in its correct holder (easy to see)
12. Now if you look down, you can easily see the lower coolant hose. An electrical connection is hooked to the top of the hose for the temp sending unit.
13. Pinch the metal wire and remove the connector.
14. Electrical connection removed15. Here is where one would normally try to remove the lower hose (after pulling up on the wire clip). But, I noticed that the temp sending unit was easily removable. So, I pulled out an old concrete mixing tub (Home Depot - $10 a few years ago)
16. Placed it under the car next to the passenger ramp
17. Carefully loosened the overflow tank cap (my car was still hot so I used a rag)
18. Using a standard flat blade screwdriver, unscrew the bleed valve in the upper radiator hose.
19. Then, once the pressure has been released, using a sizeable rag as a shield, remove the temp sending unit by pressing in each of the side tabs and pulling up. It should come right out. Keep the rag their until the pressure is low enough.
20. I had a considerable amount of fluid drain out. I caught about 98% of it.
21. At this point, I started to blow air down the overflow cap using a paper towel over the opening. Blue fluid definitely came out. (Sorry, not going to show action pics of this stage)
22. After several minutes of this, I decided to switch to my shop vac. Before placing it on the overflow tank, I ran it for 30 seconds or so to get out all of the dust (I would recommend cleaning your vac if its bad...I may have had a few bits of dust fly into the overflow reservoir). It was unbeliveable how much came out. Just make sure your on "blow" and not "suck".
23. Overall, this method resulted in 1.5 gallons of fluid.
24. Finally, need to get to the block drain bolt. Under the car, look up at the passenger side of the block. You will see a cannister (some say it is for the VANOS). Remove the (EDIT) 10mm bolt and spacer.
25. Spread open the hinged tabs and push the canister up and to the right. You can now easily see the block drain bolt.
26. Using a series of extensions and a universal joint on a 3/8 ratchet, I was able to break this 13mm bolt loose. Like others have said...this can be messy. I had a large rag between me and block. Once loose, the bolt fell into the pan. Mostly, my arm was drenched. The pan caught another 1/2 gallon. I have read to replace the aluminum bushing on the bolt, but I just flipped it over and reused it.
27.From here it was easy....replace the block drain bolt and the VANOS cannister.
28. Replace the temp sending unit and the electrical connector
29. Mix up a gallon of BMW coolant (blue) with a gallon of distilled water ($.85 at the local grocery store)
30. Find a funnel (I cut the distilled water jug and used it and a buddy to hold it) and pour the 50/50 mix into the reservoir. Mine took the whole 2 gallons.
31. Turn the car on and the heater on full blast.
32. Reinstall the bleed valve, but leave it barely cracked open.
33. My coolant tank was low and the yellow coolant warning light was on, so I had to add another 1/2 gallon of water to the system.
34. Run the car for a while and watch the temp guage....any sign of high temps....shut her down!
35. I opened and closed the bleed valve a few times. Ultimately, I stopped seeing fluid come out.
36. Reinstall the fan shroud and the 2 air duct pieces.
37. Reinstall the undertray (I left mine off for a couple of days to watch for leaks)
38. With all of the fluid spray that occured....I gave the engine bay a quick hose down."
__________________
Comment