||054 109 119 A
||054 903 137
||11.2 x 866*
||034 260 849
||12.5 x 915
||035 260 849 C
||12.5 x 992
* Beware! The owner's manual may incorrectly list 11.2 x 825.
Most of the bolts and tension adjusters are 13mm; however, you'll need a
17mm wrench and socket to get at the alternator pivot bolts.
The alternator tensioner uses a gear on a toothed rack. It is very easy to
push the alternator in too far and get the gear off the rack when trying
to remove the belt. If this happens, you'll have to completely loosen the
gear bolt to get the gear back on the rack. The gear tensioner has a very
large hex nut that forced an anonymous owner to use a 10" adjustable wrench
(affectionately know as a "knuckle buster") to adjust the tensioner gear.
The front pivot bolt is best accessed from outside the car through the lower
Remember to back off the A/C tensioner when you're done to get it off the
The manual says that the belts are tight when you can move them the following
distance at a center point between the pulleys:
A/C 5mm (5/16" ????) -- somebody's got a problem with unit
P/S 10mm (3/8") -- the power steering pump belt should
NOT be as tight as other belts on the car. It should be rather loose actually,
just to the point where it doesn't squeal. The main cause of failure on PS
pumps is the bearings, and that's due to overtightened belts!! Believe me,
you don't want to know how much a new pump is.
Alternator 2mm (5/64") new
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:
Water Pump (P/N 034 121 004, <$60 for German, <$40 for Graf, stay away
from GMB! [Japanese]) If you decide not to replace the pump, you'll still
need a new o-ring (035 121 043) for it! (new pump comes with o-ring)
Stationary Idler Pulley (Tensioner) (<$40) Put in freezer to ease
Front Crank Seal (<$10)
Front Cam Seal (<$10)
All accessory V-Belts (they have to come off anyway)
Flush Coolant (it's got to come out with the water pump anyway)
Inspect the aux. radiator. This will be a good time to replace it if it's
Special Tool 2084 - crank pulley positioning tool ($65 to $95 to buy, Blau
may rent this tool). Alternative is to use the parking brake (all wheels
on ground!) with transmission in 5th gear. The transmission and brake will
react the torque. You decide.
Special Tool 2079 - crank pulley torque tool, not required, few have used
it but it is listed in Bentley.
Special Tool 3034 - timing belt idler pulley puller, not required, easy to
jackstands or ramps
torque wrenches (need a big one for the crank bolt)
large drive breaker bar ( minimum 1/2" drive)
cheater pipe (to extend breaker bar)
3/8" drive hex bits including 5 & 6mm (buy these if you just have Allen
wrenches, they are worth it)
combination wrenches and sockets in 10, 13,15, 17, and 22mm
Bentley manual - not required but good back-up
Loctite 242 (blue)
(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.
Spray WD-40 or other penetrating lubricant on the mounting bolts for the
A/C compressor, alternator, and the hydraulic pump.
Put the idler pulley in the freezer (aids in installation).
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.
Disconnect the battery. Make sure you have the radio
security code if it is the OEM head unit.
Remove grill, remove sensor mounted on back of grill and leave attached to
Remove plastic belly pan.
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.
Disconnect headlight washer hoses from the bumper, then set bumper aside.
Remove the plastic shield mounted in the center, where the bumper was. Note
orientation before removing.
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.
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.
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.
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.
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.
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).
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.
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
Remove the upper timing cover with the two socket head nuts and the lower
cover with 2 bolts.
Remove the spark plugs to allow the engine to turn over easily.
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.
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
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.
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.
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.
****WARNING: DO NOT TURN THE CRANK OR CAM WITH THE TIMING BELT OFF!!!!****
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.
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.
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
Install the rear shield, and install pivot bolt for water pump through shield
but do not tighten it.
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.
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.
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!!!!
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.
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.
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.
Install timing belt covers.
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.
Now reassemble the rest in reverse order.
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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