This write-up is Robert Kaplan's, verbatim.  He sent nice pictures with it, but (with one exception) I was unable to include them because they didn't cross properly from his platform to mine.  Many thanks to Robert for his efforts.  The one exception picture dramatically illustrates the balance chain drive gear wear problem.

INTRODUCTION

I performed this procedure on a 1991 9000 Turbo.  I decided to undertake this project after reading about catastrophic failures on 1991-1992 model year 9000's resulting from a failure of the balance chain crank sprocket.  My experience validated this concern as the balance chain crank sprocket on my car was about 60% worn.  My car had 155,000 miles at the time I did this project.  Picture.

 This is a fairly large undertaking.  I had the benefit of time since I had my car stored in the garage for the winter.  I don’t really have an estimate of how long it took to do this since I worked on it sporadically over the period of about a month.  However, my best estimate is that the entire project could be completed in a couple of days of steady work by a decent amateur wrencher like myself.

GETTING STARTED

 This project requires removal of the water pump.  Removing, and particularly reinstalling, the water pump is a lot easier if the ac compressor is removed.  I would at least consider getting the ac system discharged in cars already using r134a.  Most shops that do a/c work will evacuate and recharge, when you are ready, for a reasonable fee.  The reason professional assistance is required (beyond the environmental issues) is that a deep vacuum will be necessary before recharge.  In cars using r12 (freon), which are model years 1992 and older, I would consider leaving the ac compressor in place.

 

REMOVING THE CRANK PULLEY (HARMONIC BALANCER)

 I call the “harmonic balancer” the crank pulley.  Because that’s what it is.  Since it’s hard to justify $300 for a pulley, the Saab Dealer calls it a “harmonic balancer.”  They also call salespeople “client advisors.”  But that’s a different tirade.

 

REMOVING THE TENSIONER ASSEMBLY

 

REMOVING THE POWER STEERING PUMP AND BRACKET.

 There are two hoses attached to the power steering pump.  

 The bolts holding the power steering pump onto the bracket can be seen through the holes in the power steering pump pulley.  

 Now you have to remove the bracket.  

 

REMOVING THE ALTERNATOR

Don’t even try to remove the alternator without first removing both the power steering pump and the power steering pump mounting bracket.

REMOVING (AND REFITTING) THE WATER PUMP

 I was able to remove my ac compressor since my system had conveniently discharged itself.  I am sure removing and refitting the water pump is easier if the ac compressor is removed than it would be otherwise.  If you can, remove the compressor and the compressor mounting bracket.  The water pump is right below the ac compressor.  If you don’t remove the ac compressor, then I would suggest getting a hand mirror so that you can see what’s going on down there.

The water pump is held onto the timing cover by three bolts.   There is also a fourth bolt that is the lower bolt for the ac compressor mounting bracket, which screws into the top of the water pump.  If your car is a turbo, there is a bolt with a 19mm head securing the turbo cooling line to the back of the water pump.  In all cars, the water pump also connects directly to the block via a round connector.  The last fixed connector is the metal pipe which runs across the back of the timing cover right above the oil pump.  In addition, there are 2 rubber hoses connected to the pump.

First, unscrew the bolts holding the pulley onto the water pump and remove the pulley.  I did not do it this way because I did not think to loosen the pulley bolts while the belt was still on.  I was not able to remove the bolts without some tension on the pulley, but I really didn’t try that hard.  Since I had removed the ac compressor, I was able to pull the water pump out with the pulley still on.  It might be possible to loosen the water pump pulley bolts by just grabbing the pulley with one hand and loosening with a wrench in the other hand.

 Disconnect the rubber hoses by loosening the hose clamps and pulling the hoses off.  Next, if turbo, remove the 19mm bolt at the back of the water pump.  One look at that bolt and you are going to groan.  Yes, that bolt must come off even though seeing this bolt, and getting a wrench on it, are 2 different things.  However, hopefully the 2 hours I spent trying to get at this bolt will save a lot of time and aggravation for others.  Here’s how: Get a 3/8" extension bar of at least 18" in length.  Attach a u-joint to the end of the extension and attach the 19mm socket to the u-joint.  Get underneath the car.  Starting from the opposite side of the exhaust, push the extension bar up toward the bolt staying as level with the bolt as you can.  Basically, you run the extension directly below the air intake and the turbo to the back of the water pump.  With your other hand, support the u-joint and push the socket on to the bolt.  NOW remove the bolt.

 Next remove the lower bolt for the ac compressor bracket.  You may have already removed this if you removed the compressor and bracket.  Note, when removing this that the wire for the oxygen sensor is attached here.  Below the ac compressor bracket bolt are the top 2 mounting bolts for the water pump.  Remove these 2 bolts.  At the bottom of the water pump is the third mounting bolt.  Remove this also.

 Now pull the pump to your right to separate it from the metal hose running across the timing cover.  Then pull the pump toward the right and down to pull it out of the block.  As soon as the pump is free, it can be removed from the car.  With the ac compressor in place, I am not sure if the pump can be removed from the front or if it has to go out through the right fender.  If the ac compressor is removed, just pull the water pump up and out.

Look at the long tube on the back of the water pump to see if the connector is attached.  If it’s not there, reach up to where the water pump goes into the block and pull the connector out.

If you are replacing the water pump, as I was, then you need to separate the 2 halves of the pump.  The replacement is only for the front part.  Unscrew the bolts holding the pump together and pull the back part off.  Throughly clean the mating surface of the back part of the pump you will be re-using.  I used a utility knife and then brake cleaner to get the old gasket off.  The new pump comes with a new gasket and new o-rings.  When reassembling the pump, I used Loctite 518 (anaerobic gasket maker) on both sides of the gasket because this is what Townsend recommended.

Next, turn your attention to the round connector.  Remove the old o-rings and throughly clean this whole item.  I again used brake cleaner to clean this inside and out.  Fit the new o-rings and work petroleum jelly into them.  Fit the large end of the connector into the end of the water pump.  It’s a tight fit so tap it in with your hand.

When it comes time to reinstall, everything is the reverse of removal.  However, pay attention when putting the back of the pump into the block that you don’t bang up the o-ring trying to figure out where the hole in the block is.  If you crane your neck, you can see the hole from the side.  Also, if you didn’t remove the ac compressor, note that the top of the pump mounting flange goes under the lower mounting bracket for the ac compressor.  When reattaching the pulley, torque the nuts to 6 ft./lbs.  I was able to do this holding the pulley in one hand and using a ratchet wrench with the other.  I did not say that was easy.

 

REMOVING THE OIL PUMP

Looking at the front of the timing cover, the oil pump housing is bolted directly to the timing cover.  On 91-93's, the oil pump cover is a large irregularly shaped cover held on with bolts.  On later years, the pump cover is round and is held on (I think) with a snap ring.  The crank position (knock) sensor is attached to the front of the oil pump housing with 2 torx screws (I believe they are T-25).  Remove the sensor.  I covered it with a finger from a rubber glove.  Remove the wire for this sensor from the mounting bracket on the timing cover and let the sensor hang behind where the power steering pump used to be.  Later model cars may not have this sensor.

 Remove the 17mm nut from the bottom right corner of the oil pump housing.  This is the oil pressure relief valve.  Remove the spring and the little cup the spring fits into.  You may have to stick your pinkie in to get the cup out.  If getting the cup out is a big problem, try again after the pump is removed.

Remove the 12mm bolts securing the pump housing.  Now remove the longer 13mm bolts.  Pull the oil pump housing away slightly from the timing cover.  Reach your hand behind the pump cover and pull the oil pump housing off the crankshaft, making sure that it all stays together.

Examine the back of the oil pump housing.   Those 2 gears are the oil pump.  Picture.  Note that the outer gear has a small dot on it that you can see.  Make sure, when you put it back together, that this dot is again facing you.  You are supposed to keep the alignment of the gears the same when you put it back together.  Meaning that the same teeth on the gear sprockets should interconnect at the same place.  I am not sure I was totally successful doing this.  If you are going to be replacing the main seal, you will have to remove the gears.  Otherwise, I suppose you could just leave them in.  Also, if the gears look at all questionable, it is a very good idea to replace them since weak gears may not be able to re-prime the pump when the engine is restarted.

 

REMOVING THE TIMING COVER

Now everything is removed except the metal hose running across the timing cover and the bracket holding wires to the side of the timing cover.   Picture.

 

BALANCE CHAIN AND SPROCKETS

The balance chain system consists of a chain, four sprockets, one tensioner and two independent guide rails.  There is also a third guide rail which is actually the outside edge of a timing chain guide.  The sprockets include a crank sprocket, an “intake” sprocket, an “exhaust” sprocket and an “idler” sprocket.  The intake and exhaust sprockets are attached to the respective intake and exhaust balance shafts. Picture (note the color code text on the picture page). 

 Before disassembling anything, examine the intake and exhaust sprockets.  You will note that there is a groove on the edge of each sprocket which lines up with a groove on the balance shaft housing.  There is also a raised mark on the balance shaft behind the sprocket which should be aligned with the groove on the sprocket.  When the motor is at top dead center, these marks should all line up.

To remove the balance chain:

In theory, the balance chain crank sprocket simply pulls off the crankshaft.  However, the drive dog for the oil pump rides on the crankshaft directly in front of the balance chain crank sprocket.  I could not get the drive dog to budge.  What I ended up doing was putting on work gloves and pulling out on the balance sprocket.  With much effort, the drive dog finally moved a little.  I then tapped it back to where it was with a hammer and screwdriver and pulled again.  Eventually, the drive dog and sprocket came off the crankshaft.  I think the problem was largely just the film of dirt on the surface of the crankshaft.  I throughly cleaned the exposed portion of the crankshaft and the inside of the drive dog and was able to refit it without too much trouble.

Another thing to examine here is the ridge into which the cutouts in the crank sprockets fit.  This ridge is actually a removable key.  Make sure that this key is seated neatly in the groove on the crankshaft and that it fills the cutouts in the sprockets.

I did not find it necessary to remove the intake or exhaust sprockets.  These sprockets and the idler sprocket appeared to be in very good condition and I decided not to replace them.  The intake and exhaust sprockets would be tricky to get off because the bolts rotate with the sprocket (as opposed to the bolt on the idler sprocket, which does not).  If I had needed to remove them, I probably would have wrapped the old chain around the sprocket, held it tight with vise-grips and then tried to get the bolt off.  I suspect that refitting new sprockets would be even more of a challenge than removing the old sprockets because the intake and exhaust sprocket have to be torqued fairly tight, and the groove in the sprocket has to be aligned with the mark on the shaft.

My 91 came with metal guide rails.  The guide rails seemed in good condition and I did not replace them.  I understand that later model year cars have plastic guide rails.  These are very cheap and should be replaced.  The chain and tensioner should also be replaced as a matter of course.

 To re-assemble:

REFITTING THE TIMING COVER          

The next step is to refit the timing cover.  Before doing anything, you must thoroughly clean the mating surfaces of the timing cover, block and sump.  I used a full can of brake cleaner getting the oil residue off.  Note that the timing cover fits onto posts in the block.  On my car, the original grease was still there, but was dried out.  The cover will not want to go back on if you don’t get rid of this grease.

Also, examine the head gasket.  Mine had a little bit of abrasion on the bottom right side.  I trimmed this off with a razor blade.  The clearances are so tight refitting the timing cover, that lose material from the head gasket could bunch up and cause the timing cover not to go all the way on, or damage to the head gasket.

The last thing to take a good look at is the black o-ring in the oil sump surface.   I read a post on the TSN about someone getting this bunched up putting the timing cover back on and subsequently losing oil pressure and the motor.  This was not an issue on my car since it didn’t move at all.  

The next step is to apply the sealant.  However, before doing that, I tried a couple of dry runs figuring out how the timing cover fits back on.  This proved to be very useful when I was ready to put it back on for real.  I was also able to reassure myself that the sump o-ring would stay in place.

 

REFITTING THE OIL PUMP

This is a good opportunity to replace the oil pump o-ring and main seal.  The main seal is not that hard to do as long as you note how deep the original seal was.  Use a screwdriver to pry out the old seal.  Use a tube (or socket) the same diameter as the outer edge of the main seal to pound the new one in.  A plastic plumbing pipe extension piece can work nicely.   [QUASI NOTE: I missed the proper depth when I put in a new seal.  As a consequence, the new seal leaked for a month or so, but it did seal effectively after it had some time to wear in.]

The o-ring for the oil pump is another story.  If you have one of the early 2.3's like mine, the o-ring is about the diameter of a cake plate and fits into zig-zagged groves on the back of the oil-pump cover.  Plan on an hour to get that sucker in well enough to get the pump cover back into position.  The problem is that o-ring is so big and the grooves are so erratic that as soon as you get it in on one side, it pops out somewhere else.  It does actually fit even though you will surely think you were sold the wrong part.  Try to avoid throwing the oil pump cover across the garage as I am sure it would be expensive to replace.   [QUASI NOTE: Maybe something like Vaseline or axel grease would help to keep the o-ring in place.]

 

REFITTING THE REST

 The rest is basically just the reverse of removal.  Remember (I didn’t) that the alternator has to go in before the power steering pump bracket.  Also, the top bolt for the alternator is the one with the washer.  Make sure that the oxygen sensor cord is correctly secured.

  Don’t forget the following basic things:

    1.  Re-install the engine oil drain plug and fit a new oil filter.

    2.  Re-install the radiator drain plug.

    3.  Refill with engine oil, steering fluid and coolant.

You are supposed to prime the oil pump before restarting the car.  The way to do this is to crank with the DI cassette disconnected until the oil light goes out.  I just cranked for about 10 seconds.  If you start the car and the oil light does not go out, shut down right away.  You may have a weak oil pump unable to re-prime.

The power steering pump may be noisy at first because there will be air in the system.  I have found that turning the wheel from full lock to full lock a few times will cure this.  Also, it takes a while for the air to bleed out of the cooling system so keep an eye on the coolant level