Jack in FL

From what I have gathered, the timing belt is used to time the valves and pistons so they don't crash each other. It also drives the water pump.

The accessory belt is used to drive the power steering, A/C compressor.

Please correct me if the above things are wrong. What actually drives the accessory belt and is it also called the serpentine belt?

Also, when replacing either, what should be changed as well?

Sorry about all the questions, it's just it's almost time to do the timing belt and I don't wanna go into the factory/shop knowing nothing :-\

Thanks!

ShoppingKartRacer

you are right about your observations. yes, serpantine belt, accessory belt, and sometimes called driving belt, are the same thing. Look at

http://dev.12v.org/repairs/tbelt.php

for the replacement procedure.

When replacing tbelt and accessory belt, you need to replace the following:

Timing belt $39.10
Accessory drive belt $22.41
Water pump $54.04
Water pump gasket $4.59
Coolant thermostat $21.15
Thermostat O-ring $0.60
Timing belt tensioner $40.85
~1 gallon of antifreeze (phosphate free antifreeze that is safe for aluminum engines)
~1 gallon of distilled or de-ionized water
Rubber O-ring for the coolant drain plug on the engine block (heater pipe o-ring) $1.15
Rubber O-ring for the coolant drain plug on the engine block (water pipe o-ring) $1.15

The prices are from autopartsworld.com, the cheapest place you will ever find audi parts on

don't buy them yet, make sure your shop lets you provide your own parts. GOOD LUCK!

Malcolm100CSq

You got it mostly right - the "access." belt = serpentine, also drives the alternator

marcogyver

qoute: What actually drives the accessory belt and is it also called the serpentine belt?

The crankshaft (d), bottom/center of the engine, has a pulley which the timing belt and serpentine belt are connected to. When the engine is running the crankshaft is driving everything.

<img src="http://pictureposter.audiworld.com/40588/timing8.jpg">

Other items that I would replace in addition to ShoppingKartRacer's list just because your in there type stuff:

-idler bearing for timing belt
-sepentine belt tensioner
-water wetter to antifreeze
-check and inspect coolant hoses since you've got it drained
-radiator flush

QCRAZY

<ul><li><a href="http://www.performancemotorcars.com/">http://www.performancemotorcars.com/</a</li></ul>

ShoppingKartRacer

I almost bought all those parts on autopartsworld.com to replace my timing belt. I'm doing it on performancemotorcars.com now.

Jack in FL

Wow, thanks for all the info guys! I think I can go into this pretty well now.