E46 Oil filter housing gasket replacement

Oil filter gasket replacement
I had a small oil leak on my 2005 325i E46 and I just couldnt find it. I eventually thought that it was the sump but dreaded the job so I left it. I then bumped into a mech around the corner and he told me that the sumps are quite strong but I should check the oil filter gasket and surrounding. So after a bit of YouTubes and reading, I found the leak. It was the oil filter gasket. I bought a new gasket from BMW for R70.00 so it was not too bad, I prefer the originals if affordable.

Heres what you will need:
Tools:

Socket Set and spanners: 10mm, 13mm, 16mm, 17mm, 32mm
Flat Screw Driver, pliers
32mm Spanner

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Finding the leak
To find the leak, I had to remove the air filter box to inspect the location before it was confirmed. From the left hand side fender, I had to make my way in past all the cables, pipes, etc to get a close look at the engine block and this is where I found the mess. It was around the area of the rear of the alternator (red wire is alternator + lead).



Air Box Removal:
First start by using a long nose to remove the push clips. Grip the clip and pull slowly once it has been pulled approximately 1.5cm out, wiggle the base to remove the entire clip. These could break as they weather over time so be careful if you dont have replacements.



Then we move over to the side to disconnect the airbox.
1. Remove the clamp on the air intake hose using a flat screw driver or a 8mm socket
2. Remove the electrical connector marked 2.
3. Remove the 2 x 10mm bolts marked 3
Once those are removed and the 3 pin clips, remove the pipe from the air box and simply lift the entire unit from the car.



Time to make space to work.
Fan and Fan Shroud Removal:

Now we need to remove the Fan and the Fan Shroud (plactic thing around the Fan) and the fan. At this point, I need to state that this is a 2004 325i AUTOMATIC. I do not have an electrical fan, This car has a viscous fan which bolts on to the water pump.

Standing by the drivers fender, remove the 2 electrical connectors. You need to press down on the release clip and then wiggle the plug (the part with the wire) from the connector.



Now remove the long screw using a T25 torx key. There is a piece of plactic that acts as a washer, be careful not to loose it.



Now move to the front of the car near the bottle. There is a little push clip by the arrow that needs to be pulled and adn removed using the flat screw driver. The camera could not get into that are as I took the pic before removing the air box.



The electrical cables and the screws and clips for the shroud are now removed. Time to remove the fan. There are 2 ways to do this.
1. place the 32mm spanner on the fan nut (as per below) and give it a knock in a clockwise direction and it should break the lock, then manually turn the fan till it comes loose. Be careful not to let it fall on the floor as it will break. Or 2...
2. Place the spanner on the nut and use a clutch removal tool to jam the water pump (my home made tool) and pull the spanner and tool together to break the lock. I prefer it this way as I think you can damage the water pump with the knock if hit too hard. You can get the proper one online http://www.ebay.com/bhp/bmw-fan-clutch-tool. I already had everything open so I made a plan with the tool. Once the fan is completely loose, place it in the shroud and pull the shroud up while holding the fan.



Pulley, Fan Belt and Alternator Removal:

IMPORTANT: Draw a picture of the fan belt path as it will help later on when fitting it all back together.

To remove the Fan belt and pulley, Use a power bar with a 16mm socket. Attach the socket to the pulley tension nut and turn in a clockwise direction. This will remove the tension on the belt. Slip the belt off the alternator and power steering pump at the bottom.



Next, remove the cap on the pulley marked 2 above using a small screw drive, it just clips off.



Alternator Removal:
Use a 16mm socket and a wrench to remove the very long bolt. This is the 1st alternator bolt. You cannot see it from here, but there is another long 16mm bolt below the bottom pulley. Remove that bolt as well. these are the only 2 alternator bolts. Unfortunately I did not get any pics from the lower alternator bolts.
Note: when you installing the alternator again, use some Q20 on both the ends that slide into the bracket so that it is easy to adjust and align for the bolts to go in easily. I struggled without the Q20 as it was not easy to align the holes.
Once you are done with the bolts, disconnect the negative battery terminal. Now use the 17mm socket to remove the positive lead from the alternator as well as the electrical socket.
At the back of the alternator is a black plactic air intake pipe. Unclip the pipe and remove it from the car. You may need to push it from the bottom and find a way to get it out. The bottom was easier for me.



Now we can remove the alternator by simply wiggling it and it should come out.
Oil Filter Housing
Now, its time to remove the Oil filter housing.
Remove the oil filter. I was due for an oil change as well so I drained the sump using the 17mm socket.
Remove the bolts marked 1-6 and KEEP THEM IN THE ORDER REMOVED. I left the on the table in a '2' shape to remember which hole the came out from as they are different lenghts and I didnt want to fidget to find which goes where.



Now remove the oil hose.



Remove the electrical plugs as below:



Now using a screw driver, lever the oil filter housing away from the engine.



Using a screw drive, pry the housing away from the engine. You can now see teh engine block and the broken gasket. There was a lot of old oil and grime so I used a mixture of engine cleaner and petrol and used the compressor to clean it out. Remember to close the oil ducts on the block before getting any water out.
Now replace the gasket on the housing. Remember to clean out the grooves nicely. I also used a small nail to make sure that there is nothing hard stuck in the grooves. Dont be forceful to avoid any damage.








Now that you are done, you need to put everything back in reverse.
Remember:
Q20 for the alternator bracket - it helps
The fan is a little tricky and screws on anti clockwise.
Dont overtighten bolts
Clean up nicely - you dont get this opportunity often, or should I say you dont want it often.
Its the best time to replace fan belts, oil filter, oil, and any pulleys if necessary