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Timing belt replacement for a 5-cylinder '91 200q20v

Timing Belt Replacement Procedure

The timing belt in this picture (not from my car!) is glazed, and cracking. Further investigation showed a seized idler pulley, which means the belt was constantly rubbing against the metal. Amazing it lasted this long! So, spend the extra few dollars, and put in the new idler pulley. Remember that the 200q20v 3B engine is an interference engine, meaning lots of valves will hit the pistons and bend if the belt breaks.

This pictures shows my '91 200q20v after removing the front bumper. The bumper is held on by 2 big bolts (use a ____ mm hex wrench through the cutouts in the bottom of the bumper). After removing the bolts, remove the philips-head screws securing the brake cooling ducts to the bottom of the bumper, and pull the plastic bumper cover forward a few inches. Now, disconnect the turn signal bulbs and let them dangle. Now, slide the plastic bumper cover straight forward and off. It's nice to have a helper, but not required. Put the bumper cover aside with the two bolts and philips-head screws, as you won't need them for a while. I've also removed the grill; removed the 13mm nuts securing the auxiliary radiator (which can then rest on the ground as shown), and loosened the lower intercooler hose. You'll note that I've also loosened the driver's side connection for the lower intercooler pipe and removed the two securing pieces that join the lower pipe to the intercooler. The pipe is inserted an inch or two into the intercooler on the driver's side, and uses a rubber o-ring to seal it with the intercooler. Pull the pipe forward and back to loosen it as you remove it and set it aside.

I removed the "Michelin-Man" hose end where it attaches to the pipe leading to the throttle body, and left it attached to the intercooler. Now, remove the two bolts securing the intercooler to the upper sheet metal, and work the intercooler free. This is probably a good time to inspect the intercooler, connecting hoses, lower pipe, etc. to see if they need replacing (rubber and intercooler gasket, for example), or cleaning and painting.

Now, crawl under the loosen the bolts for the alternator and air conditioner compressor; then loosen the bolts for the power steering pump. Remove the belts and label them.
Now, remove the timing belt upper and lower covers. They are held on by two bolts (___ mm hex wrench). There are two spacers on the studs which attach the cover; remove them and set them aside. Now's a good time to check the tension on the timing belt. Grab the belt between your thumb and first finger about midway between the camshaft pulley and the waterpump, and try to twist it 90 degrees. Your belt may be a bit loose; but mine was fine, and I reinstalled the belt at the same tension. Grab the belt on the other side, between the idler pulley and camshaft pulley, and get a feel for the tension on that side, too.

Don't start taking the timing belt or pulleys off yet; still more to do, first.

Pull the distributor cap, and let it hang to the side out of the way. Don't pull off the wires, unless you're changing the cap as well. If so, transfer the wires one at a time so that you don't mix them up. If you look at this distributor rotor, you'll notice it's in poor shape; the distributor cap center post was mostly gone. The rotor in this picture is pointing forward, and is lined up with the small mark in the edge of the distributor body (at this angle, the mark looks higher, but from straight on, it's centered). That's where it should be to change the timing belt.

This picture shows the window in the transmission housing where the timing mark on the flywheel is visible. (The black rubber hose at the top of the picture is the crankcase breather hose.) Inside the window is a metal pointer which must be aligned with the Top Dead Center mark on the flywheel (a "0"). I marked this "0" with white paint once I found it, for easier future reference.

Now, take your 22mm socket and breaker bar, and place it on the crankshaft pulley bolt. You'll initially align a "dot" stamped into the camshaft pulley with the valve cover gasket on the driver's side of the engine. The dot is stamped into the engine side of the pulley; there may be a second dot on the front of the pulley, but ignore that one.

Turn the engine slowly clockwise while watching the camshaft dot, until it is aligned properly with the cam cover gasket. Now, look at the flywheel for the timing mark. You may find it easier to spot the timing mark by slowly moving the crankshaft back and forth using the socket and breaker bar. If you don't find it, don't worry; that just means you are 180 degrees off. Turn the crankshaft pulley until the camshaft pulley has gone one entire revolution, and realign the dot with the cam cover gasket. Now, look for the timing mark again. Once you see the mark, line up your three points of reference:

camshaft pulley dot with the cam cover gasket on the radiator side;
Top Dead Center "0" mark on the flywheel; and
Distributor rotor pointing to cylinder No. 1 (and mark on distributor body towards front of engine).

Now we're ready to get to work. Now that the engine is properly aligned at Top Dead Center, install the crankshaft pulley securing tool (Audi part number 2084).

(Alternate methods to secure the pulley are available, but I strongly recommend using the proper tool; if you can't buy, borrow, rent, or make one, see this link). The tool mounts onto the crankshaft pulley and the front engine mount. You need to move the rubber support on the engine mount forward (just pull on it) to give the tool room to be mounted. This picture of the crankshaft pulley shows the cutout for the tool about where it should be; between 10 and 11 o'clock. (Note that this pulley has already been removed........ didn't take a clear shot with it in position.)

Now that the crankshaft pulley bolt is free, pull out the pulley and inspect it. The pulley also works as a harmonic balancer; it's made of rubber and metal, and absorbs vibration from the accessory belts and prevents their damaging the engine. Make sure it's in good shape, then set it aside.

The back side of the crankshaft pulley, showing the key that locks the pulley to the crankshaft (along with the mega-torqued bolt).

Here's a closeup of the old crankshaft oil seal, installed on the crankshaft. The white material inside the crankshaft is the old threadlocker used the last time the belt was changed; this should be cleaned out at this time.

New crankshaft oil seal, ready for installation. Note that the water pump is removed.

Here's the removed water pump, impeller side. The two slots on the bottom allow the pump to pivot on the upper bolt, increasing and decreasing tension on the timing belt.

Here's a view of the block with the water pump and idler pulley removed. The thermostat is visible in the mounting hole for the water pump. Note that the metal inner upper timing belt cover is still in place; we did not change the camshaft oil seal, so we did not remove the camshaft pulley, which is required to remove the inner belt guard. Its possible to slip the water pump out from behind the inner guard; just don't overly bend it.

At 01:30 PM 4/1/98 -0500, you wrote:
>Hi All:
>
>Did my timing belt and water pump yesterday. I wanted to replace the idler pulley but couldn't get it off. I don't have the special puller and my regular puller wouldn't fit in the confined space. No, I didn't >pull the IC. Any McGiveresque solutions out there?
>
>Mark Pollan, '86 5KCSTQ 250K Miles
>=20
Harbor Freight tools has a cheap steering wheel lock plate remover for $6.99. Just use that and the washer and nut that comes with it. Get a 10mmX1.5 boltX80mm long, then cut 1.5" off of each leg. File or grind 2 parallel flat surfaces on the end of the bolt (so you can grab it with a crescent wrench). Fits perfectly. To remove pulley put washer on bolt and stick thru hole in puller. Thread bolt into pulley and try to keep the legs in line with the oil pump housing boltheads. Turn bolt to pull out pulley. DONOT use the mounting bolt to install the pulley!!! On my 4kq, you can use the puller to press in the new pulley. Remove bolt and washer, then thread on nut that came with the puller, then the washer. Reverse the puller so the legs face the body. Place the head of the bolt with another washer against the face of the pulley right where the holding bolt goes. Holding the end of the bolt with a crescent wrench, use another open end wrench to unscrew the nut. Make sure the pulley is straight before you apply real pressure! You may have to repeat several times, take your time and go slowly. Popped right in for me. YMMV
Regards,
- -Tony
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Another method is to use a round electrical box (like for a ceiling fan), with washers and a similar bolt to that above. I've also used the cover plate to further reinforce the metal box, so it doesn't get crushed by the head of the bolt and washers... chris

As we all know, timing belt failure can be not only expensive but embarrassing. Changing the timing belt on an I5 engine requires removal of the harmonic balancer and pulley assembly from the front end of the crankshaft - the torque required making this a bit of a problem. Without a doubt the best way is to employ the Audi special tool (2084) to hold the system immobile. Another way is to put the car in gear and stand on the brakes - placing great strain on the transmission.

Allan Jones (ampj-at-tiac.net) and Mike Tipton (miktip-at-worldnet.att.net) of the international quattro mailing list have developed a third method.

1. Strip accessories and turn engine to TDC using the distributor mark, "0" mark on the flywheel and the mark on the rear of the camshaft gear.

2. Either remove a single transmission bolt - the easiest is the one directly behind the flywheel timing aperture - or obtain a spare (Audi part # N 010 488 3 - M12 x 85).

3. Directly below the bolt removed, and below one or two sensors, are two holes in the side of the flywheel housing. These may be hard to see around the bulge - a long light and a mechanic's mirror are useful. The front hole of the pair is the one used.

4. While watching the hole in the mirror, turn the engine 15 to 20 degrees clockwise (viewed from the front) using a socket on the camshaft pulley. The flywheel holes are quite large and hard to miss if the engine is turning slowly - and should be perfectly lined up to take the bolt.

5. With the bolt in place, the crankshaft bolt can be broken loose. Leave it finger-tight.

6. Leaving the crankshaft bolt and harmonic damper in place for the moment, remove the blocking bolt and turn the engine back to TDC.

7. Change the timing belt and anything else you feel like doing.

In the immortal Audi phrase, refitting is the reverse of removal. Assemble the engine at TDC. Once the crankshaft pulley bolt is a little over finger tight, the engine can be turned to line up the holes again.

The torque given for the crankshaft bolt in the Audi microfiche - 350 Nm or 258 lb ft - assumes that Audi's torque multiplier (2079) is being used. Without 2079, the correct torque is 450 Nm or 332 lb ft. Audi recommend coating both threads and mating surfaces with AMV 188 000 02 -an anti-corrosion compound - but do not state that the bolt must be renewed, unusual for a high-torque fixing.
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I prefer the audi tool, as the potential for damage using the above method seems too high (to me...). A number of people own the tool, and use it every 60,000 miles, so they don't feel bad about loaning it out for a weekend or so....