Bmw 335i 2011 Belt Diagram

DIY Guide: N54 335i Serpentine Belt, Tensioner, Upper and Lower Pulley Replacement
First DIY Guide for me
Just paying it back to the community for all the knowledge I learned here.
Being a Realtor; I don't mind getting my hands dirty.

I am by No Means a Mechanic, but had my share of experience owning my 2007 335i Sedan for over 2 years. So I take no responsibility for any errors, and your own mistakes.....I take no responsibility for providing this guide, whether you follow it or not.

If you feel you can contribute to this guide; please by all means PM me, and I will edit as needed.
No Oil Cooler on my car.

Additional tasks I had to do at the same time. (not covered here.....but this gave me a lot of room to work with.)
Inspect Spark plugs.
OFHG (Oil Filter Housing Gasket).......2nd time after 11 months.
Removing Radiator Fan Only.

Required Tools.
Torx bits.
T20
T25
T50
T60

Sockets:
6mm
10mm - for belly Pan
1/2inch breaker bar, 15 inch or longer.
New Tensioner and Pulleys should come with new Bolts.....Mine did...and all OEM.

Total Cost of Parts to me at least:
Tensioner Part# 11287563927: $104.16
Belt Part# 11287628652: $50.11
Upper Pulley Part# 11287556251: $44.07
Lower Pulley Part# 11287557851: $44.07

Step 1. (Lots of DIYs) on how to do the following
Get your Car up on Ramp. or jacked up front end on jack stands.
Remove belly pan....15-17,,,,,10mm screws. (give you move light while working)
Remove engine cover. (optional.....I did....which means removing Remove charcoal filter and cowling.)

Work on a cold car so you don't have to worry about burning yourself on a hot engine.

Step 2: Remove 2 screws using T20 on Air Intake and remove air intake duct to Air Filter Box.

Step 3:
6mm to loosen Hose clamp off of Air Filter Box and remove air duct.
Also turn and release the other pipe shown in picture below.

Step 4:
2 Arrows on the Right on the picture, Simply unclip the Coolant hose and AC Line.....just pull it gently.
The Arrow on the left is optional but this clip is Latched.....press on the front to release the right side of the clip.
The 2 Circles are T25 that need to be removed. These hold the Air Duct. When removing, they will be accompanied by an metal grommet that is inserted in a rubber housing on the air duct support. you will have to pull them out.
Now the Air duct can move out of the way....just barely to give you access to the job at hand.

Step 5: Extremely Important step:
Draw the Map of your Belt.....else you won't know how it goes back on.
here is what I drew.....Man I am an Artist.

Step 6: Remove the Belt by turning the Tensioner T60 clockwise to release the Tension and Slide Belt off of Tensioner.....breaker Bar really Helps here.

Step 7: Remove the Dust Caps off of the Tensioner and Both Pulleys by prying the Dust Caps off using Small Flat Head.
Place your other hand in front of each dust cap, else they will fly off. Also NOTE: all 3 are different sizes.....so note which goes where.

Step 8: Remove the Tensioner and Both Pulleys....you will need a T50 for all.
here are the Torque Specs officially from Dealer.
http://www.convertunits.com/from/N+m/to/ft+lb
when installing the New Tensioner, DO NOT pull the lock pin, untill you have torqued The Tensioner and both pulleys. Finally using Breaker bar on a T60 remove the lock PIN and Mount your New Belt. (Don't forget the to Put the Dust Caps Back on).

Keep in mind and double check that the grove in the Belt is in the grove on each wheel.
Finally when you are ready to add the belt to the tensioner.....do it last.....alternator first, tensioner Last.

Reverse Order to complete.
Have a Friend or Wife at the Wheel and ask them to Start the Car once all is done. and advise them to turn off immediately if any issues arise.

Bash Shah
Sutton Premier Realty