Belt Replacement

P/N

Size
Timing Belt 054 109 119 A

(147 teeth)
Alternator 054 903 137 11.2 x 866*
A/C 034 260 849 12.5 x 915
Hydraulic Pump 035 260 849 C 12.5 x 992

* Beware! The owner's manual may incorrectly list 11.2 x 825.

V-Belt Tips

Timing Belt Replacement
The 20V engine is an interference design. This means that if the timing belt breaks while the engine is running, the pistons will come in contact with the valves and cause expensive damage. For this reason, it is important that the belt be changed before the end of its life. It can be a labor intensive job, but it's definitely easier than replacing your pistons and valve train. I think Audi may recommend changing it every 90K mi., but 60K is probably a bit safer.

While the front end is apart, you should do some preventative maintenance so you don't have to repeat the job again in a few months. Here is a list of other parts to replace:

Tools:

Instructions:
(Dave Kase, Peter Schulz)
Time Required: There are a lot of variables. It could take anywhere from 4 to 12 hours.
Note: all references to right or left are in the proper sense, as sitting in the car facing forward.

  1. Spray WD-40 or other penetrating lubricant on the mounting bolts for the A/C compressor, alternator, and the hydraulic pump.
  2. Put the idler pulley in the freezer (aids in installation).
  3. Drain coolant. See Coolant Flush page for instructions, or just drain the main radiator and go through the timing belt removal procedure. Be prepared for a HUGE flood when you pull the water pump if you just do the radiator now.
  4. Disconnect the battery. Make sure you have the radio security code if it is the OEM head unit.
  5. Remove grill, remove sensor mounted on back of grill and leave attached to car.
  6. Remove plastic belly pan.
  7. Remove bumper: (Sedan) pop 2 caps off on top of bumper, just behind headlight washers. Remove 1 socket head bolt from each side.
    (Coupe) Remove two allen bolts from underneath each side of the bumper. Prepare something to lay bumper on near installed position.
  8. Disconnect headlight washer hoses from the bumper, then set bumper aside.
  9. Remove the plastic shield mounted in the center, where the bumper was. Note orientation before removing.
  10. Remove the top cross member (body color piece above and between the headlights) by removing the small brace between cross member and the main rad., then remove the mounting bolts on each side as well as a bolt securing the secondary radiator in place. The hood release wire runs below this cross member and must be removed from each of the 3 hooks. It is not necessary to remove the wire, just unhook it from the cross member.
  11. Remove the auxiliary radiator by removing the 2 hoses. A plastic guard which surrounds the hose connections can also be removed at this point. Remove 2 nuts securing the aux rad to the lower support (from under the car). The auxiliary rad will come out.
  12. Remove the lower cross member (body color piece between and below the headlights) - This must be removed to allow the installation of the 2084 crank positioning tool. There may be variations on this tool and some may not require the removal of this support. The support is easy to remove anyway and will make the work area a little clearer. First remove the wiring harness from the support by squeezing the back side of the clips together and pushing the clips through the holes in the cross member. This will leave the clips in tact for reinstallation. Then remove the attaching bolts.
  13. At this point mark the alternator, hydraulic pump and A/C compressor as to their adjusted position before removing the v-belts. While you'll still have to go through the adjustment procedures at belt installation, it will give a basic reference.
  14. Remove the alternator belt - loosen the 13mm head bolt then turn the 22mm (21?) nut which drives the alternator to loosen the belt. Be careful not to damage the teeth on the "star" bolt.
  15. Remove the A/C belt - loosen the adjuster (bottom center), loosen slide bolts on front and back of compressor. Be careful not to damage the teeth on the "star" bolt. If the compressor is frozen in position, use a hammer and block of wood (beat on mounting bolts heads, not big $ compressor unit).
  16. Remove hydraulic pump belt - loosen 2 pivot bolts facing away from each other at pivot of pump near valve cover (on right side of pump). Loosen bolt on left side of pump, just forward of the adjuster, behind the pulley (13mm head). Loosen the adjuster and remove the belt. It may be necessary to remove 2 pivot bolts to remove belt. Be careful with the long bolt on the hydraulic pump, they tend to stretch and brake easily.
  17. Remove the alternator belt guard (? - bracket that looks like a "V" on its side located toward the bottom and in front of the top timing belt cover) by removing the lower attaching bolt and loosening top bolt (top of guard has slot).
  18. Remove the upper timing cover with the two socket head nuts and the lower cover with 2 bolts.
  19. Remove the spark plugs to allow the engine to turn over easily.
  20. The harmonic balancer is the 6"(?) diameter piece on the very front of the crank with grooves in it for the v-belts, the crank pulley is the smaller toothed piece behind the balancer and drives the timing belt. Ensure the transmission is in neutral and turn the engine over with a socket on the crank pulley/harmonic balancer bolt. Align the cam pulley "." with the "V" on the valve cover. This will also align the harmonic balancer mark (small cut on edge of v-belt groove closest to engine) with cast indicator. Be sure BOTH the cam pulley mark and the harmonic balancer mark are lined up with the appropriate indicators (it is possible to have the crank mark aligned and the cam will be 180 degrees out of alignment). This will put the crank at TDC on compression stroke for #1 cylinder. An excellent way to mark the set up (assuming the current belt is properly installed) is described later. But, it is a good idea to add a few reference marks at this point as a back-up (the factory indicators are a bit vague). Use your white-out, paint pen or better yet a scribe (can't wash off scribe marks when cleaning parts). A good reference for the cam pulley is the valve cover seam . The pulley can be marked on both sides of the center bolt head along this seam. The cylinder head can also be marked on either side of the top pulley "spoke". The harmonic balancer and cam pulley can be marked by using a slide square/level. Put it vertically across the center of the pulley and level the square. Then mark the top and bottom edge of the balancer or pulley along the square. This may be overdoing it, but I talked with a guy that had his off by one tooth (talk about detonation!!). He had to do it again.
  21. At this point feel how the timing belt is tensioned. This will help you when you tension the new one. It might be a little loose but you can get the basic idea.
  22. Some have removed the water pump from behind the rear timing belt cover by loosening the cover but leaving it behind the cam sprocket. If the cover is to be removed, the cam pulley must be removed. Before attempting to break the cam pulley bolt loose, be sure it is held in place so it can not turn. This can be done with the special tool or with a brass drift placed through the cam pulley and against the engine (crude but it works). It is not recommended to use the tb to hold the pulley in place. Should the pulley slip within the belt, the valves may contact the pistons...not good. Break the sprocket bolt loose with a 24mm wrench or socket (but leave it in place). The pulley is keyed so orientation will not be lost when removing.
  23. Remove the 4 small bolts from the harmonic balancer. Then install the 2084 tool and remove the harmonic balancer bolt with 27mm socket. An air impact gun may break it loose or use a breaker bar with cheater extension. Bolt will turn slowly at first (like it is twisting off -- yikes!). Remove harmonic balancer only and leave small crank pulley and the timing belt in place on the crank. An alternative to using the 2084 tool is setting the parking brake (all wheels on ground!) with transmission in 5th gear. The transmission and brake will react the torque.
  24. Here is an excellent way to make reference marks: pick a tooth on the cam pulley that is in contact with the belt and mark pulley and belt, pick a tooth on the small crank pulley that is in contact with the belt and mark pulley and belt, count the teeth on the belt between these marks. The newly installed belt should have the same number of teeth between marks. White out or a paint pen can be used for these marks but they may inadvertently be cleaned off. A small scratch with a scribe will ensure the marks are not lost. The previously mentioned marking procedures should also be done in the event the small sprocket is accidently removed with the harmonic balancer.
  25. ****WARNING: DO NOT TURN THE CRANK OR CAM WITH THE TIMING BELT OFF!!!!****
  26. Remove the idler pulley if you plan on changing it. Take out center bolt and use the 3034 tool or carefully pry pulley off. Do NOT use a standard puller to remove it, or you may break the bolt behind the oil pump.
  27. If removing the rear timing belt shield, remove the crank pulley (24mm head bolt broken loose earlier). Then unbolt the shield as necessary. One of the shield bolts also holds the water pump on so you may see some leakage at this point (drip pan ready?). At this point, take some time to clean the front of the engine. If leaving the seals in place, clean lightly around them. An agressive cleaning near the seal could cause it to leak from dirt or damage. It is also the time to get into cam shaft seal or crank shaft seal replacement if you chose to do so. This is advised if you have a noticeable oil leak in this area or would like to do it while your in there. See Scott Mockry's Engine Tech Tips page for more details.
  28. Remove the 2 adjusting bolts on water pump and it will come off. If you did not fully drain the engine before, you will now -- big gush of coolant. Thoroughly clean the surface of the engine where the pump goes. Pay attention to the surface where the pump will mate. Take your time and scrape it well and use solvent to clean it. This surface must be very clean and smooth !!!!! Get out the new water pump and o-ring. Apply a light coating of Vaseline to the o-ring and place it in the water pump. Install water pump with only the 2 adjustment bolts but do not tighten. Be very careful not to pinch the o-ring The Vaseline will help hold it in place and allow it to slide when adjusting.
  29. Install the rear shield, and install pivot bolt for water pump through shield but do not tighten it.
  30. Clean and lightly oil the mating surface of the new idler pulley. Install the new frozen idler pulley by pushing it in the recess by hand then gently tapping the INNER area with a brass drift to make sure it is seated in place, or find a socket that fits the surface of the pulley and use that to tap it home. Do NOT draw idler pulley into place with the little bolt that holds it in place. You may break it!!! You can also measure the depth of the socket on the engine and length of the plug on the idler to get an idea of when the idler is against the bottom of the socket. Torque bolt to 7 lb-ft.
  31. Install camshaft pulley. Camshaft pulley gets torqued to 48 lb-ft with a drop of Loc-tite. Again, use a brass drift through the cam pulley spokes or special tool to hold it in place.
  32. Mark two teeth on the new belt same as the old belt. Line these marks up with the marks made on the cam and crank pulleys. Install the new timing belt by putting it around cam pulley, water pump and tensioner then installing crank pulley. It may take a few tries to get it right. Use the factory markings and your own markings to ensure you get it right. Better take extra time now to be sure rather than find out when you start the car!!!!
  33. Once the belt is aligned, put the harmonic balancer on. Install the 4 bolts through the balancer into the crank pulley. Install the large center bolt and using the 2084 tool, torque crank pulley bolt to 330 lb-ft (258 lb-ft if using the 2079 tool). If you do not have a torque wrench that can be set this high, use an extension on a breaker bar and do the math with your body weight at a specific moment arm (110 lb person on a 3 foot long bar). NOTE: Bentley states the crank bolt should be torqued to 258 lb-ft. This figure is the setting on the torque wrench when using the 2079 tool. The additional moment arm on this tool gives an actual torque of 330 lb-ft.
  34. Once the belt is in place, pry the water pump to tighten the timing belt and snug down (3) bolts. Beware that the water pump bolts have some kind of sealant on them to prevent oil leakage, since at least one of them goes through an oil gallery. Recoat them with Loctite 242 or get new bolts w/sealant from a dealer. The Bentley states you should be able to turn the belt 90 degrees between camshaft sprocket and water pump (with the thumb and forefinger). Take your time here and be sure you are happy with the tension. Contrary to popular belief, tighter is NOT better. It has even been suggested that you stay on the loose side allowing a little more than 90 degrees (to a maximm of 120 degrees) twist.
  35. Tighten water pump (3) bolts to 15 lb-ft. At this time, turn the crank pulley at least twice around and realign the timing marks for a last check. Remember it's very easy to change it now. If for some reason you hit resistance, don't force it, valves may be in contact with the pistons.
  36. Install timing belt covers.
  37. Install new v-belts. Again, not too tight. Overtightened belts wear bearings in expensive items such as hydraulic pumps!! Use marks as a basic guide but still set tensions accordingly. Belt should be able to twist 90 degrees between pulleys or 4-6mm deflection between pulleys. On A/C compressor, back adjustment bolt off engine block after slide bolts are tightened (note: front A/C compressor bolt also holds together an oil sealed surface so be sure to tighten properly. If not tightened, it will leak.
  38. Now reassemble the rest in reverse order.
  39. When filling coolant, be sure to open bleeder valve on heater hose where it goes through the firewall. It may be difficult to get flow here until the car is started and the level in the coolant tank goes down. Then replenish the tank and when the engine gets warm, it should start to flow out of bleeder. Water can be run in the system and brought up to operating temp to help clean it out. Then drain it again and refill with new phosphate free anti-freeze.

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