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      12-23-2011, 11:27 PM   #1
F80_M3llow
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Thumbs up DIY-Replacing N52 tensioner, idler pulley and serpentine belt

Welcome everyone. As you may know i have up in the general section about changing my belt tensioner, belt and idler pulley. I completed this job successfully and will do the best i can to write my first DIY to replace the tensioner, serpentine belt and idler pulley on your N52 engine.

Parts you will need. Part Numbers Included
Mechanical belt tensioner #11287530314
Torx bolt #11287530315
Deflection pulley (Idler pulley) #11287535860
Serpentine V-belt#11287628650

Tools you will need.
Ratchet and various size bits.
T60 torx bit to unload the belt tensioner
Small hands are a plus

This DIY will be strickly only for replacing the belt tensioner the belt and Idler pulley. It is your job to figure out how to take out the air box. Most of us know how to remove it. So easy a caveman can do it.

1. Ok the first step is to get to know where everything is in your engine. Here i marked where the idle pulley is located and the belt tensioner.


2. Removing the Air duct.
To remove this get a torx bit and unscrew the two screws on each side then simply pull out the intake duct.


3. Taking off the serpentine belt.
Here is where it gets annoying. The tensioners on are cars are really hard to unload. Get a t60 torx bit and place it in the torx star in the tensioner i will circle it in red. Now to make this easier stand behind your passanger front panel and place the ratchet in and turn clockwise while your other hand slips the belt of the tensioner. Now if you are turning it clockwise and it does not move then you need to put some elbow grease in, dont be paranoid just use some strength and you should see it start unloading. Our tensioners dont self lock so you have to have to use one hand to have it unloaded and your second hand to slip the belt off. This was annoying.




4. From here just remove the belt and put it aside. Just for good measure spin your tensioner pulley and if its spining freely and it sounds like it has sand in it the bearings are shot and it should be replaced, same goes for the idler pulley.

5. Removing the belt tensioner.
So from here you are going to need a torx bit with a small ratched. Dont remember what size it was but im pretty sure you guys have somne great tools. take a torx bit to the bolt marked in red in the picture and turn it counter clockwise might need some strenght to get it undone. Now once you break the bolt use your hand and take it out while holding the tensioner, once the bolt comes out the tensioner can be pulled out. The tensioner is only being held by that one bolt that should also be replaced when replacing the tensioner. Put the old one aside.



6. Removing the Idler Pulley.
To replace the idler pulley remove the protective cap with a flat head witch exposes the bolt that you have to remove. I think it was a 13mm. I dont have a picture of the bolt but will mark the cap. Turn the bolt counter clockwise to loosen the bolt undo untill the idle pulley is removed.



7. Installing the New Belt tensioner.
Now when you get your new belt tensioner it will come unloaded and it will have a long pin leave this pin in until it is installed on the car. Put the tensioner the same way you took the old one out line it up, it can only go on one way get your new torx bolt and screw it in. Then just tighten the bolt down well.

8. Installing the New idler pulley.
Your new Idle pulley will come with a new bolt also. Just match it up and just screw this pulley in where the old one was removed. This was the easist part of the install.
Make sure the belt tensioner bolt is tightened as well as the idle pulley.


9. Installing the serpentine belt.
Now for this make sure you look at that first picture i had in this DIY and draw out how the belt goes. You should be fine. The ribbed side of the belt goes down toward the bottom of the car. Make sure you have the ribbed parts positioned correctly on all the pulleys.

10. Loading the tensioner
Now once you have the belt routed the correct way and all the pulley including the tensioner pulley. If you are a muscle head use the T60 torx bit just as if you where going to unload it turn it really hard clock wise then grab a set of pliers and pull that long pin that came with your tensioner once that pin is removed the tenisoner should load. Re-check that the belt is positioned correctly. Now just put back the intake duct and your intake box and then fire her up. CONGRATS YOU ARE DONE.


IF ANY OF YOU HAVE ANY QUESTIONS JUST POST A COMMENT OR PM ME. IF YOU WOULD LIKE ME TO ADD SOMETHING TO THIS DIY THAT I MIGHT OF MISSED LET ME KNOW ALSO. GOOD LUCK MY FELLOW GREESE MONKEYS ENJOY YOUR NOISE FREE CAR ON COLD STARTS.

Appreciate 2
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