Crawls Backward (When Alarmed)

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SAAB c900 Alternator Removal

So, here's the deal.

The electrical system on my semi-trusty SAAB c900 #2, Greenie (also known by its Swedish name, Grona) has never been quite right in the time I have owned it. It's gotten progressively worse over the last 2 1/2 years. Very long story short, after cleaning connections, cleaning grounds, etc., I have decided to replace the alternator. Lately, putting any load on the system at all causes a voltage drop.

I found that the voltage at the battery would drop from about 13.8 volts to about 11.5 under load. So new alternator it is.

Of course, I first need to get the old one out. You can read much grumbling on the interwebs about this job. To be honest, I didn't find it that difficult, you just need patience and the proper tools. I did it over a period of two days...when I got tired/exasperated, I quit. Took me about 2.5 hours total, and that includes some trial-and-error on methodology. I think I could do it in an hour if I had to do it again.

Lots of pictures, be warned!

If you look closely, you might see the alternator down there under the AC hose and the heater hoses. The first challenge is how to get at it.

Note also the red arrow - that's the throttle cable. It goes under the AC hose on my car, which is unlike my other car. I suspect somebody replaced the hose, and it wound up under the cable.

I point this out because it will come back as an issue later.

From another angle, we see the "Bosch" decal on the alternator. So it IS visible.

Some threads I've read about alternator removal have said "pull back" or "use a bungie" to hold the hoses back for access without removing them. My car is a late 900 (1991) and it seemingly has more hoses here than earlier ones.

I pondered this for a day or so and realized there ain't no way we're getting at...or removing...the alternator without removing hoses. Simple as that.

You may recall (or not) that I have an Autometer mechanical water temp gauge on the car. So first step was to take the sender out of its fitting.

This is actually good, because I mounted the fitting so the sender pointed 'up' and it would be better off angled to the right so that the sender lead doesn't make such an abrupt turn. Here's my chance to change it.

With the sender off, I then removed the clamp and hose off the end that goes to the engine block.

Not too much coolant in any of the lines, by the way - I was able to just stuff clean rags in them to keep coolant from dripping out, rather than drain the whole cooling system.

Next we undo the heater bypass hose, and the hoses at the heater core itself.

Here the top heater hose (coolant going into the heater) is off, and I'm undoing the bottom hose.

There is a bit more coolant here in the hoses, so just be aware. I did lose some - a small amount, but nothing major.

Now the whole thing can be removed as a sub-assembly...or SAAB assembly! Get it?

Ha ha ha.

If you look closely at the hoses, you'll see the four places I undid them - the hose to the block, the heater core, and that bypass line is the one to the right of my hand in this shot.

Now we have much better access to the alternator.

At this point, you should disconnect battery negative lead before proceeding.

Here's the process I used to get the alternator out - with details to follow:

First, I took off the bracket/arm for the belt tension adjustment to release the drive belts.

Then, the second step. The alternator itself is bolted onto a bracket which attaches to the engine block. The appropriate way to remove the alternator is to remove the bolts holding the bracket to the block, and then remove the alternator, still attached to the bracket.

There are three bolts that hold the bracket to the block - one at the top, one on the left near the oil filter, and one at the bottom, under the alternator.

It IS possible to remove the alternator from the bracket, but a hole or dent needs to be made in the firewall to be able to remove the long bolt holding the alternator to the bracket. My car has had this done - but it's NOT recommended. It's not difficult to remove the whole assembly. And I found that I had a difficult time accessing the left-hand nut on that bolt anyway.

Some folks have indicated it's easier to get at the bracket bolts by removing the bolt holding the alternator to the bracket part way so you can swivel the alternator, but I didn't find this necessary.

First, let's get that adjustment bracket/arm off.

Undo the adjustment bolt - it's fairly long. I used a ratcheting combination wrench, I believe it's a 10mm head.

Once the bolt is out, you can then undo the nut holding the arm that the adjuster passes through. This is a 13mm bolt.

I show both of these being removed in the picture.

I found it virtually impossible to get a clean picture of the bolt holding the other end of the arm that bolts to the block.

But I have my finger on it in this picture - if you reach down you'll find it.

Here I have a socket on it. Not too hard to get to, but hard to photograph. I think this one also is a 13mm.

Note that the adjustment bolt and the bolt it passes through have been removed.

Once the arm is out, you will be able to push the alternator forward to free the belts from the alternator pulley(s). The alternator should swivel up and down at this point. You'll need to swivel it to access the top and bottom bracket bolts.

Here's the belt adjustment arm removed.

The angle of the lens is distorting the picture - it is NOT as long as the door!

Note the bushing on the far (engine block) end - I'll replace this. If you're going to take it all apart, you should be replacing these.

Remove the wiring from the alternator. The green lead just pulls off the terminal, while the red lead going to the starter needs to be unbolted.

And there is a ground lead on the bottom of the alternator that needs to be removed. It's also bolted on.

Different years may be different, but my ground ran up under the top bolt on the alternator bracket, which we'll see momentarily.

I had to undo the ground, because it runs across the top of the left-hand bracket bolt and the bolt can't be accessed with the ground lead in place.

I used a bungee cord to hold back one of the heater hoses to get it out of the way.

Here's the top bolt for the alternator mounting bracket. Note the ground wire that goes under it.

You can swivel the alternator downward to access this bolt.

I first undid this bolt entirely. Mistake. The bolt is too long to clear the alternator with the bottom bracket bolt still attached. So I screwed it back on, but left it loose enough to swivel the ground lead to the right in order to access the left-side bracket bolt.

With the ground lead moved out of the way, and the alternator swiveled down, it's easy to see the bracket bolt to the left of the alternator.

In theory (according to the interwebs), all three bolts should be 6mm hex. However, as you saw on my car, my top bolt is a standard 12mm bolt. Not sure if this is common to late models or not. (My other car is a 1992 so I can check it).

It's not really important, just something to note.

So now we can remove that hex bolt on the left side of the bracket.

I was all prepared to use a long extension and a universal joint on my ratchet, but all I needed for the left and bottom bolts was a shorter (3 inch...75mm or so...) extension. And of course a 6mm hex drive socket.

After the left bolt is undone, you can undo the bottom bolt. Due to its location, I couldn't get a shot of it.

However, you should be able to see it looking under the alternator from the left side. Use a flashlight (torch) and you'll see it.

I was able to guide the hex wrench using my left hand on the end of the wrench and my right on the ratchet. Not too hard to get at it - you're just working blind.

After you get the bottom bolt off, you'll be able to remove the top bolt.

The three bracket bolts removed - and placed in their relative positions. Note the left bolt is shorter than the other two.

I'll clean up the ends of the ground lead before it goes back on.

The top of the bracket fits under the AC compressor bracket, so the alternator needs to be pivoted to the left to free its mounting bracket from the AC bracket.

And then the alternator can be moved down away from the block. Careful - it's heavy!

Whoo hoo. Almost there.

The alternator and its bracket are now free to lift out of the engine compartment.

The red arrow points to the location on the block where the left bracket bolt goes.

All is going well now...but recall that I pointed out the location of my throttle cable earlier? I couldn't lift the alternator up out of the engine compartment - it just wouldn't clear the throttle cable!

So I had to remove the end of the cable.

I just bent back the tab holding the end of the cable to the throttle assembly.

There's a spring clip that holds the cable to the bracket. The red arrow shows where the plastic mount on the cable is mounted.

In the picture, I've already undone the clip, and pulled the cable out of the bracket. Easy.

Then I'm able to lift the alternator up out of the engine compartment.

Success!

I'll put the alternator in a vise and remove the bolt holding it to the bracket. There are bushings on the bracket also that I'll replace.

Here's what we have with the alternator removed.

You can now clearly see the AC compressor bracket in this picture - note how its bottom fits over the alternator bracket. And you can also see the left-side and bottom alternator bracket mounts on the engine block.

I'll take this opportunity to clean up this corner of the engine compartment now that I have good access.

 
 
 
 

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