1 BMW 645 Coolant leak repair (Cap with Seal Repair and Expanding Coolant Pipe Installation w Pics) By Michael R. Brown (Estimated time to complete the job is 6-8 hrs) List of parts needed below. BMW PART P/N PRICE QTY SECONDARY AIR PIPES (pressure hose assy Y-Pipe) 11 72 7 508 270 $55.28 1 SECONDARY AIR PIPES 1-4 11 61 7 547 185 $53.17 1 SECONDARY AIR PIPES 5-8 11 61 7 547 186 $53.17 1 VENT PIPE( TO HEADS from coolant container) 17 12 7 542 540 $66.27 1 2 LOWER INTAKE SEALS (Intake Manifold Gasket) 11 61 7 521 181 $68.80 2 MISC O-RINGS (Water Pump to Heater Return Pipe ) 11 51 7 507 717 $5.08 1 MISC O-RINGS (O-Ring Water Pipe/Water Pump) 11 53 1 710 048 $6.60 2 COOLANT BMW 82 14 1 467 704 $19.95 1 Cap with Seal 11 14 7 507 278 $72.68 1 Hex bolt with washer (Cap with seal) replacements 07 11 9 905 400 $9.90 12 Profile gasket 11 51 7 508 535 $9.06 1 Return Pipe 11 51 1 439 976 $20.44 1 Feed Pipe 12 31 1 439 988 $17.88 1 O-ring 07 11 9 903 596 $6.10 2 Cooling Pipe Kit (Expanding) (ALL German Auto)760-738-4626 $644.00 1 Note: Price quotes are from the link below and would be much higher if you purchase the parts from the dealer. You may be able the find the parts cheaper at other sites too. http://www.bmwmobiletradition-online.com/index.wws?cookieid=32fa031e4a11ae4899cd2fcde5b94ff3 Tools needed - Zip lock bags (box) for nuts, bolts, etc. (Mark the bags to speed up identifying them later. - Torx socket Set $20 (Wal-Mart) - Hex socket set (Metric) $20 (Wal-Mart) - metric socket set (deep) $20 - socket extensions set $10 (Wal-Mart) - vacuum w/ small diameter attachment - feeler gauge $5 any automotive store - telescoping mirror $5 any automotive store - telescoping magnet $3 any automotive store - recipicating saw w/ metal cutting blade $55 (Home Depot/Loews) - small seal pick $10 - Automotive grease (not pictured) - Cordless drill or ratchet (speeds up the job) - Drill socket adapter (Wal-Mart) $10 - Phillips screwdriver (not pictured) - Jack and Jack Stands or Vehicle ramps ( not pictured) (Warning!!!! Never get under a vehicle supported by only a jack, because, the jack could fail and the vehicle can fall on you and injure or kill you!!!!!!!!!!!! Always use jack stands!!!!!!!!!!!
2 Reciprocating Saw w/ metal cutting blade Drill w/ 3/8 socket adapter Telescoping mirror Torx set Feeler gauge Small Pick tool Metric Hex set Telescoping magnet 3/8 Extensions 3/8 Ratchet Let s get started 3/8 Metric Short and Deep well Sockets 1. Disconnect battery in the trunk. (Negative terminal only) 2. Jack up the car and remove the front under cover. 3. Remove the gas cap (releases pressure in fuel system) 4. Remove underbody cover (Front only) ********************************************************************************************** 5. Remove the cap on the coolant reservoir and drain the coolant.
3 Loosen the red cap and drain the coolant 6. Remove the 4 torx screws and remove top engine cover
4 7. Detach the small vacuum line on the intake tube and loosen the intake tube clip next to the sensor. 8. Disconnect sensor, unclip and remove the air box top cover with the intake tube assembly
5 9. Remove 3 torx screws from the lower air box housing, slide out and remove the housing 10. Unclip cabin filter housings, turn plastic 13mm screw and remove cabin filter on driver side)
6 11. Unclip cabin filter housings, turn plastic 13mm screw, disconnect sensor and remove cabin filter on passenger side) 12. Pull up on center cabin filter housing support brace, slide to driver s side and remove
7 13. Remove torx screw holding cabin filter housing to strut tower passenger side 14. Remove 2 torx screws holding cabin filter housing to strut tower driver s side ***************************************************************************************************
8 15. Turn these plastic nuts counter clockwise a quarter turn to remove the cabin filter housing and weatherstrip (remove driver s side first).
9 16. Remove the 6 large torx screws and remove the strut brace 17. Pull up and lift off the side engine covers (they just snap out). They are snapped into 2 rubber grommets each side.
10 18. Unclip the fuel line by removing the grey clip, pushing the black piece back and slide out the fuel line Note: Catch fuel with a cup or small pan. Also, take a ziplock bag and place over line with a rubber band to catch fuel that come out later. 19. Remove 4 screws on throttle body, disconnect sensor and slide off throttle body (clean it while you have it off with carburetor cleaner.
11 20. Unclip the 2 sensors on the thermostat housing. Pull up on the wire and slide off. Note: After disconnecting the connector, push the wire back down to keep from losing the wire. 21. Carefully!!! Squeeze the connections, wiggle until they come off, and then remove the vent pipe(s) from the intake manifold to each valve cover. Note: I show both types in my picture. Note: these will most likely break when removing them. The old 1 piece design was replaced by two pipes. You may have either 1 pipe with 4 connection or 2 pipes with 2 connections. (shown in the pics below)
12 Old 1 piece design New 2 piece design (these are re-useable and have heat protection padding on them)
13 22. Squeeze and remove vent pipe on the side of the throttle body opening on the intake manifold and slide the other end off the retaining support. (front of driver's side valve cover) Slides off right here 3 23. Using a feeler gauge, gently unclip the round electrical connector on the (front) of the wiring harness from each side. It should slide right out. (See pic below for removal)
14 Gently slide the feeler gauge under the clip and pull on the connectors rubber boot and it should come right out. 24. Unclip and remove 2 electrical connectors from wiring harness. (Passenger s side) Squeeze and pull out the round ones. Pull wire up on rectangular connector and pull the connector off.
15 25. Unclip and remove 2 electrical connectors from wiring harness. (Driver s side) Squeeze and pull out the round ones. Pull wire up on rectangular connector and pull the connector off. 26. Remove 4 torx screws on top of each side of wiring harness and remove the two supports Supports
16 27. Unclip connectors each side and remove the 8 hex screws attached to the servo motors (4 each side) Remove servo motors from each side. (Mark them to insure you install them back on the correct side. They should pop out once the screws are removed, if not, just screw them out. (do not drop them) Also, stuff clean rags in the holes or cover them to prevent anything from falling in holes. 28. Lift up on the wiring harness to release it and move it outward on each side to access intake nuts.
17 29. Turn a quarter or a turn, lift up and disconnect the round connectors on the rear valve cover to the wiring harness on both the driver s and passenger s side 30. Lift out the 3 plugs on the passenger side to the ECU box.
18 31. Remove the screws to ECU Cover (I only show 1 screw but there are 4 or 5), Slide the white triangle to unlock and remove the ECU cover. 32. Loosen and remove (10 each) 11 mm nuts holding down the intake manifold on both sides. You may need a deep well 11 mm if your sockets are short. (Use a magnet to catch the nuts so they do not fall down under the engine)
19 33.. Locate the wires on the driver s side wiring harness and pull them out of the clip to give you some slack on the wiring harness to remove the intake manifold. Note: This picture is just to show you the wires (don t pay attention to anything else, you are further alone) 34. On the front of the intake manifold, unclip and pull the cable down going to each side s coils. Note: There are two wiring harness connectors that need to be disconnected on the rear of the intake manifold. You can unhook them once you pull the intake manifold forward about 2 inches 35. With the help of a second person, lift the intake manifold up and pull forward 2-3 inches to disconnect two remaining connectors on the back of intake manifold. Now lift up to clear the bolts and remove the intake manifold slowly. Note: The manifold should come right out by pushing the cable and hose down in front of the intake manifold.
20 Here is a picture of the intake manifold out of the car. 36. Remove the hose from the coolant reservoir to each side of the block (it might break but, you have the replacement) The Y connecting the hoses is plastic. To coolant reservoir
21 37. Stuff rags in the 8 intake holes on the block to prevent dirt etc.. from falling in to the engine and vacuum the area around the holes. * Follow the cable to front connector not pictured 38. Squeeze and disconnect the Y-vent pipe lying over the Cap with Seal. 2 connectors on rear and 1 in the front (not in pic). Also remove the hold down clamp too.
22 39. Disconnect, remove hold down bolt and pull the aluminum pipe out of the thermostat housing to rear. 40. Unclip and move the black cable clips to the cap with seal (You will re-use them)
23 41. Remove 11 bolts remaining bolts holding the cap with seal down. (Do not reuse them because they will break when trying to retighten them after installing the new cap with seal). The new bolts from BMW are now steel. 42. Remove the cap with seal and suck out or use a towel to remove the gallon of coolant.
24 * Note: If you are just replacing the Cap with seal stop here and put everything back together in reverse order. Note: If you are going on with the expanding cooling pipe install, follow the instructions that came with the pipe kit or continue below. There are also 3 videos on YouTube demonstrating the pipe installation and I suggest you review them several times before completing the job. Here is the one from All German Auto http://www.youtube.com/allgermanauto#p/a/u/0/uoced1jyfl4 Expanding Cooling Pipe Install 43. Using a reciprocating saw cut the OEM cooling pipe in half.
25 44. Remove the rear half of the cooling pipe 45.. Drill a hole in the front half of the pipe and using a screw driver and a block; pry the front half of the cooling pipe out toward the rear. 46. Using a pick and mirror; remove the O-ring seals from the front and rear holes. 47. Use automotive grease on the new seals and install them in place of the old ones Note: Ensure you place the seals in properly using the instructions that came with the pipe.
26 48. Install the new pipe tight, but do not over tighten. I tightened it as tight as I could by hand and used a wrench to tighten it another quarter turn. This is how the final install should look. Note: You are suppose to check the system for leaks before putting everything back together but, good luck finding the special BMW tool. Also, I did not take off the water pump housing either. You have the parts on hand if want to do it now or later. 49. Go ahead and put everything back together in reverse order. Starting with the Cap with Seal. Lessons learned - Do not reuse the bolts to the Cap with Seal because they are prone to break when retightening them after installing the new part. Also, do not over tighten them. I tightened them down snug with an extra quarter turn. - Don t forget to connect the 2 connector on the rear of the intake manifold - Be extra carefully removing vent pipes - Make sure the intake manifold is seated correctly (watch out for the clip on the last bolt on the drivers side) - When reinstalling, ensure vent pipes are fully seated. They may take a little manipulating to get them to clip on!!! This is especially important for the Y -Vent pipe, because it is under the intake manifold and if it is not seated properly you will have to pull the intake manifold off again!!! - If you get a check engine light for increased emissions and the engine idles very rough or when you press on the gas the engine runs rough; double check your vent pipes and all connecters.
27 - If this happens, check all pipes connections. Once they are seated correctly the check engine light will go out after driving for a day or so. * Congrats!!! You have just saved $2000 on the Cap with Seal Job and $9000 on the Coolant Pipe Job. Both of these parts fail around 80,000 to 100,000 miles and are known problems with the N62 engine. If you have any questions or you live in the Atlanta area and would like for me to complete the jobs for you, shoot me an email at robe370@aol.com