2009 TDI Serpentine Belt

so2315

Veteran Member
Joined
Aug 25, 2008
Location
Chicago, Ill.
TDI
2009 Jetta Sedan
Just had the emission fix about a month ago. Tonight while driving the battery light came on. When I got home, I figured a new alternator was in store so I popped the hood to see what I was up against. I noticed the serpentine belt was laying on the bottom of the engine compartment. Alternator pulley turns freely but the belt has a chunk missing so I need a new belt. How do I go about this? Looks like there is no room from the top side, so do I need to go from the bottom?
Also, since the belt was thrown off I have no idea on the route of the new belt. Has anybody done this on their TDI?
 

Henrick

Top Post Dawg
Joined
Aug 24, 2010
Location
Ireland
TDI
Golf VI TDI, 77 kW (CAYC)
Firstly, you are very lucky that you found the serpentine belt laying on the bottom and not under your timing belt cover. Go buy a lottery ticket.

Secondly, serpentine belts quite rarely fail with no reason. Check all the components it touches - crank pulley, tensioned pulley, tensioner itself, alternator pulley and the alternator clutch itself too. Most likely a failure of one component resulted in a dropped belt.

And yes, this needs to be done from the bottom of the car.
 

meerschm

Top Post Dawg
Joined
Apr 18, 2009
Location
Fairfax county VA
TDI
2009 Jetta wagon DSG 08/08 205k buyback 1/8/18; replaced with 2017 Golf Wagon 4mo 1.8l CXBB
There are a few guides put together by folks that cover the timing belt. this includes info on the accessory belt.

http://www.myturbodiesel.com/images/a6/timingbelt/serp1.jpg


http://www.myturbodiesel.com/wiki/cbea-cjaa-vw-jetta-golf-jsw-tdi-timing-belt-removal-part-1/

http://pics.tdiclub.com/data/500/CR_Timing_belt_procedure_Rev2.pdf

these belts are usually pretty good. so there is some reason for the failure.

look close for any extra tools/parts when you drop the bottom plastic cover under the engine compartment.
 
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so2315

Veteran Member
Joined
Aug 25, 2008
Location
Chicago, Ill.
TDI
2009 Jetta Sedan
Well I did find the answer to my problem. After taking the wheel off I dropped the belly pan. After loosening the last bolt to the rear of the pans the tensioner pulley rolled off the rear of the pans and dropped to the floor.
The pulley base that goes into the spring assembly sheared off.
In looking at a video it appears to be alot of work to get to the rear bolt of the tensioner. I'm not sure I would have the patience to drop the coolant downpipe and I always struggle getting VW sensor plugs undone.
Has anybody replace their tensioner and have any tips or tricks to make it easier?
 

meerschm

Top Post Dawg
Joined
Apr 18, 2009
Location
Fairfax county VA
TDI
2009 Jetta wagon DSG 08/08 205k buyback 1/8/18; replaced with 2017 Golf Wagon 4mo 1.8l CXBB
I never did it, but a couple folks casually said they replaced this tensioner

the mounting bolt is on the side opposite from the belt, so will take a bit of doing to get to it.

it does seem like the first video that googles up includes a few extra parts removed.

Search may be your friend.
 

CRWalker

Active member
Joined
Apr 20, 2016
Location
York, PA
TDI
2009 Volkswagen Jetta Sportwagen TDI CBEA
CR Serpentine Belt Tensioner 101

I personally have done this myself. Most important point I have to make on this replacement: 25nm is the magic number for the bolt holding the tensioner to the alternator bracket.

The key to successful installation after that is to have an allen key socket thin enough to slip inside the cavity where the bolt goes. It's been about 2 months since I had to replace this tensioner, so the details are a little fuzzy. However, I do know my tool selection very well and know I had to use about four or five successful combinations of an extended reach allen key socket (4,5,6 or 7 mm - I don't remember the exact size of the allen socket in the head of that bolt), a short allen key socket, a 6" 3/8" extension, a locking flex head 3/8" ratchet, and possibly a 3" 3/8" extension.

- I did not remove anything coolant related.
- After removing tension from the topside and pulling the belt off, then I went underneath and removed the tensioner bolt.
- I did remove the cold side intercooler soft hose (from intercooler to throttle body)
- I did remove the cold side intercooler hard pipe
- I do own a $250 15 degree flex head 1/4" torque wrench and used this to torque this bolt.
- I work for an automotive service company and was able to do this in book time including taking time to clean the gunk from my intercooler hose & pipe. (I did this repair on the lift at work while doing this in book time. Doing this off the ground on jack stands is probably about twice or three times as long and as difficult depending upon skill level.)
- I have a manual car, so I'm not sure if the DSG thermostat housing connects to a cooler for those transmissions. If that does get in the way, then this is why I didn't have to touch anything coolant related.
- Hand starting that bolt was definitely the most challenging part of the entire job, I spent a good 20 mins on this step alone with about ten or more unsuccessful attempts. (I used my entire mental dictionary of old sailor words and came up with a lot of fun new ones during this step.)

I have this thread set to email me when others reply, so I will be available to answer questions. I know I'm forgetting details, but I have a very good external-initiated-recall memory. Please don't hesitate - this was one of the most frustrating things I've done on this amazing-yet-infuriating vehicle, but was a great learning experience for me!

CRWalker
 

Tdiguy89

Member
Joined
Mar 2, 2021
Location
Western nc
TDI
01 beetle alh 5mt, 02 jetta alh 5mt 12 jetta sportwagen cjaa dsg, 13 A3 cbea dsg
I will be attempting this at home on my ramps... I do not yet know how I'm going to get the radiator shroud out with the limited clearance. Vehicle is a 2013 audi A3 with CBEA/DSG. I feel that these are lower than the jetta sportwagens, which I also have.

If you have any further pointers, that would be awesome!
 

Tdiguy89

Member
Joined
Mar 2, 2021
Location
Western nc
TDI
01 beetle alh 5mt, 02 jetta alh 5mt 12 jetta sportwagen cjaa dsg, 13 A3 cbea dsg
I will be attempting this at home on my ramps... I do not yet know how I'm going to get the radiator shroud out with the limited clearance. Vehicle is a 2013 audi A3 with CBEA/DSG. I feel that these are lower than the jetta sportwagens, which I also have.

If you have any further pointers, that would be awesome!

So I just did this job yesterday on 2 jackstands and im actually about to button up the belly pan and be completely finished this morning.

THERE IS A SHORTCUT

But it has its flaws, I found both myself.

Remove airbox, engine cover, belly pan, passenger wheel and passenger wheel well liner.

SHORTCUT: looking from just in front of the transmission, look just past the oil cooler and you'll see a decent size hole in an aluminum bracket. This is the blind hole that the 13mm bolt for the tensioner is in.

It took (1/4"drive): 13mm deepwell,1" extension, swivel joint, 8" extension 1/4male-3/8female adapter (3/8): 8" extension and a 3" extension.

With a bit of patience, you'll get it.

SHORTCOMING: when I put the new tensioner in, I didnt have enough tension on my socket fishing pole. Have a partner remove the old tensioner, clean the pocket and install the new one while you hold the socket fishing pole in.

I ended up getting the socket sideways somehow and the bolt wedged against it. Thought it was tightening but it wasn't. Went about 10 rounds and tried to push/pull the tensioner, the tensioner wasn't attached.

If this happens to you, remove the "throttle tube" (intercooler to intake pipe). Clean the intake inlet well all the way around or get sand inside it... Drain the water out of your intake by disconnecting the lower portion, unplug the ac connector clip, you can do the map sensor before or after you remove the pipe. 2 t30, one by the harmonic balancer and one behind the ac compressor. Will take some finesse to get it out. Now you can basically touch everything you need to. I routed my arm coming in sideways from where the airbox goes.

25nm is the spec I've found for the tensioner bolt.

Cheers!
 
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