# Timing Belt and Water Pump Replacement; 1990 Audi 90 Quattro



## Asphalt Unlimited (May 24, 2008)

Ok guys, there's already one in the DIY section, but i figured i'd type one up with photos and DETAILED instructions on how to Change a timing belt and water pump on a 1990 Audi 90 Quattro. So, here it goes...

Step 1: Remove grille and Outside Temperature Sensor. The Temp sensor has three prongs on it, all you have to do is squeeze them and pull it out. The grille should have two screws on the top, and once those are out it should come up and then out.


Step 2: Remove the front support. It will be four 10mm bolts on the outter edges (2 on each side) and three 8mm bolts between them, and two screws at the bottom. Now before you just try to yank that piece out, take a look at the hood release cable that stretches across it, there are three black clips holding it there. To remove from the clips, put your fingers on the cable, push up out of the clip, then push to the front of the car.


Step 3: You don't HAVE to do this step, but it helps to do so. Remove the secondary radiator. It will be the two hoses on the driver's side, and two 10mm bolts on the bottom that you must get from the bottom, and a 10mm swivle socket helps a lot.


Step 4: Next are your accessory belts. The first to come off is the Alternator. Loosen up the 13mm bolt that holds the alternator to the block, then use a 13mm wrench on the gear ratchet on the alternator bracket, turn CLOCKWISE to loosen the belt, and COUNTER-CLOCKWISE to tighten back up. Next is the compressor for the a/c. It has a 13mm bolt and nut on the bottom for the slide, a 15mm bolt on the top and bottom of the side that bolts to the block. Lastly is your power steering pump belt. 15mm bolt on the block ear, 13mm BEHIND the pully, and then to adjust tension, use the 13mm long bolt to move the pump up and down.
Step 5: Remove the 7 shaped braket from the passenger side of the block. It will be two 17mm bolts. HINT; The bottom bolt comes out, the top one does not need to, the bracket is slotted so you can just pull the bracket up.


Step 6: Remove the plastic belt cover from the block. This is helt on using two odd looking nuts. The are flare nuts, but on backwards, to take off, use a 6mm allen socket. You may have to adjust the water pump to remove it, if so, see steps 11 and 12.


Step 7: Now to remove the crank pulley. NOTICE!!! Remove the four 6mm allen blots from the pulley FIRST. If you remove the center bolt and then try to pull the pulley off, you may end up pulling the inner crank drive for the timing belt. So remove the four 6mm allen bolts, then the center bolt, which is 27mm. You may need to put the car into gear to keep the motor from turning (if you have the car in the air), if so, put it in 5th gear to keep the motor from turning over


Step 8. Remove the lower metal cover from in front of the timing belt. This is removed by a 5mm allen bolt on either side.
Step 9: Thread the bolt back into the end of the crankshaft. Put socket back on the bolt. If you put the car into gear to keep the motor from spinning, put in neutral now. Turn the motor over until the Little dot on the camshaft pulley meets up with the arrow on the valve cover. Mark the dot and the arrow with a paint marker or something of the like so that it is easier to see later on. pick a spot on the crank gear and on the block itself and mark with a paint marker to make sure you'll have both the cam and the crank lined up. Pull the spark plug wire on the first cylinder, and then the spark plug with a 5/8" spark plug socket. Stick a long screwdriver or a long 1/4" drive extension down in the hole to make sure that the piston is at top dead center (as far up as it can physically go in the cylinder).
Step 10: Remove the camshaft gear, even with the belt still on. it is easier to loosen and tighten the belt with the water pump once the new water pump is on. I know it's not metric, but i used a 13/16 socket, and it worked fine. If you don't have an impact tool, put the car back in gear for this step and this one only.
Step 11: Remove the Inner metal plate. Sould be three 10mm bolts on the front, a 13mm bolt on the passenger side, and a 13mm bolt for the water pump that must come out. Place the plate off to the side.
Step 12: remove the remaing bolts from the water pump. This will be a 6mm allen bolt on the top of the driver's side, and a 13mm bolt right below it. Also make sure the bracket goes on the same way it came off. The pump should now come right off.
Step 13: Clean the area around where the water pump mounts too with a piece of emry or sand paper. wipe dust off with a shop rag or towel. Put the new seal on the new pump, lube up with some motor oil, but not much, just enough to keep the seal wet. Put the pump on the block, and put the bracket with the 6mm allen bolt and the 13mm bolt back in to hold it on. Bolt that larger metal place back onto the block. now once the passenger side water pump bolt is in, go ahead and loosen the other two back up a bit.


Step 14: Re-install camshaft gear, making sure it is aligned with the marks. Verify that the cranshaft is also aligned with the timing marks. you will notice how the paint marker has now made life a little bit easier







. once they are aligned, wrap the belt around the gears and the pulley. Rotate the water pump to set the belt tension. Correct tension is acheived when you can grab the belt with two fingers, and twist the belt just to 90 degrees.


No all you have to do is reverse the process. Remember to bleed the cooling system after you've re-filled it with coolant.


_Modified by Asphalt Unlimited at 7:52 AM 6/22/2008_


----------



## littlegreek (Nov 24, 2006)

*Re: Timing Belt and Water Pump Replacement; 1990 Audi 90 Quattro (Asphalt Unlimited)*

VERY cool!this is alot more detailed than the other one.Just two things,there is a TDC reference mark on the flywheel which can be viewed through an a hole on the driver's side of the tranny.Oh,did the 27mm crankshaft bolt back off easily?many people use a crankshaft holding tool.


----------



## Asphalt Unlimited (May 24, 2008)

*Re: Timing Belt and Water Pump Replacement; 1990 Audi 90 Quattro (littlegreek)*

no the crank pully bolt did NOT come off easy. I had a 1/2" impact gun on it for about a minute straight before it would let loose. but that's why i put it in 5th gear to keep the motor from turning over.
-Shaun


----------



## europa96 (Mar 6, 2006)

*Re: Timing Belt and Water Pump Replacement; 1990 Audi 90 Quattro (Asphalt Unlimited)*


_Quote, originally posted by *Asphalt Unlimited* »_no the crank pully bolt did NOT come off easy. I had a 1/2" impact gun on it for about a minute straight before it would let loose. but that's why i put it in 5th gear to keep the motor from turning over.
-Shaun


What did you use to tighten it?


----------



## Asphalt Unlimited (May 24, 2008)

*Re: Timing Belt and Water Pump Replacement; 1990 Audi 90 Quattro (europa96)*

i used the impact gun to tighten it as well. I don't know what the torque specs on it are, if you would like i can probobly get them. I just kind of torque that kind of stuff by feel, there's alot of lee-way in the kinda stuff.
-Shaun


----------



## europa96 (Mar 6, 2006)

*Re: Timing Belt and Water Pump Replacement; 1990 Audi 90 Quattro (Asphalt Unlimited)*

Yeah, I've been reading up on the procedure. What kind of impact gun do you have? I've been reading something like 330 ft. lbs.


----------



## Asphalt Unlimited (May 24, 2008)

*Re: Timing Belt and Water Pump Replacement; 1990 Audi 90 Quattro (europa96)*

I have a matco impact gun that's like 600lbs. but i feather the trigger, i don't go all out on it, just kinda "buzz, buzzzzzz, buzz" play with it a bit.
-Shaun


----------



## MikeHock (Dec 9, 2004)

*Re: Timing Belt and Water Pump Replacement; 1990 Audi 90 Quattro (Asphalt Unlimited)*

Interesting. Ive always done my 5cyl timing belts a tad different, mainly because I take off the crank sprocket/pulley as one assembly due to replacing the crank seal. Ive never taken the pulley off of the sprocket.
Always used the proper timing belt tools (or you can make them) to hold the crank while you loosen/tighten the crank bolt.
Nice write up!


----------



## Asphalt Unlimited (May 24, 2008)

*Re: Timing Belt and Water Pump Replacement; 1990 Audi 90 Quattro (MikeHock)*

yeah you SHOULD always use the correct tools. I've got all the specific tools for the newer audi's, but nothing for this style. But throwing it in gear to hold the crank in it's place works well







.


----------



## saab kiwi (Jan 7, 2011)

*Broken drive gear*

Hi everyone, first time poster, but with a bit of a problem. 

My daughter has a 1990 Audi 90, belt broke just before New Year. The broken belt has been removed, but the toothed drive gear on the flywheel appears to have failed - I am unsure whether the gear had previously been over torqued and has failed due to fatigue or has destructed in removing the flywheel. 

Questions are 

1) anyone else seen this? 
2) is this an easy to get part ? 
3) Anyone know the part number? 

Thanks 

Ian


----------



## Mcstiff (Feb 1, 2002)

Why not pull the bumper?


----------



## kuma85 (Oct 22, 2007)

This is great! Thanks!!!


----------



## Audi100A1 (May 21, 2016)

*1990 Audi 100 A1 timing belt replacement*

Hey guys and gals, I have a 1990 Audi 100 A1, I want to replace the timing belt and struts. Anyone know where I can get videos of that? Thank you.


----------

