1 8t Replace Alternator

This was done on a 2000 Passat, ATW 1.8T.

Please make sure you disconnect the negative terminal on your battery before attempting this.
If you do this going easy, it may take a few hours. Newman and I did this twice (because of a faulty replacement part), first time it took us around 6hours (we wasted quite a bit of time), the second time (I was doing everything along with taking pics) it barely took us 30 minutes.
Note: When buying the replacement alternator, please get the new unit tested before going out the shop. We ended up buying a faulty part and had to do this procedure twice.
Also, take a picture or draw/use a diagram of the belt routing for reference later on.

On with the procedure.

Step 1: Remove throttle body intake hose & the power steering fluid reservoir cover (for better clearance)

hose/cover removed:

Step 2: loosen the belt tensioner with a crescent wrench, hooking on the ear of the tensioner and turning it clockwise

Step 3: use a clutch nut (available for rent from Kragen/Autozone; just ask them to rent you a fan clutch removal tool kit) and an allen socket wrench to remove the radiator fan so you can access the lower bolt of the alternator.

Step 4: dismount the fan and move it towards the side

Step 5: Use a allen socket to remove the lower alternator bolt

Step 6: Remove the top bolt, be careful not to strip the bolt (like newman and I did).

We ended up filing the sides of the bolt and used a curved jaw plier to remove the bolt. We also replaced it with an M8 1.0 type bolt for easier use going forward. Plier Pic

Step 7: Remove the electrical connections on the back of the alternator, there is one plastic socket type connector and one metal connector with a nut on it.

Step 8: Take out the old unit, it is mounted pretty snug so you may have to use a small pry bar to push it out, you would need to maneuver it a bit around the coolant hose on top(no need to remove the coolant hose). Our passat had a 90amp valeo unit, others may have a bosch one. this would be a good time to upgrade your alt as well. i bought a 120 amp valeo unit which is basically a v6 passat unit. place back the new one.

Step 9: Connect the wires on the back, place the alternator back and align the bolt holes and mount it accordingly. you can also mount the fan back in to place and tighten its bolt.

Step 10: Use the crescent wrench (clockwise) on the tensioner ear to bring it forward and route the belt as per your diagram/picture. I want to mention that it's a good idea to replace the belt at this time but I didn't have enough time to do it.

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