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Alternator removal and reinstall x51

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I'm trying to replace my voltage regulator and have been following the very fine and detailed guides around on the net.

However, I'm utterly unable to get my alternator out. I'm also unable to get it back together, so as it is right now the car is not running. Whops.

Are there any great tricks to get this going? Just copious amounts of wd40 on the pressed bushing to get it pushed back in?

And then "twist and turn" the alternator out ? I've never seen the pictures for this on a x51 as mine is, could the metal intakes be

tighter then the plastic ones or am I just too afraid to "punish" it to get everything loose?

I never thought I'd have to make a topic to get an alternator loose, but here I am oops.gif

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Here is what the service manual says. I suspect you may have to loosen the intake even more.


1. Disconnect the battery and cover terminal or battery. Undo the fastening screw for the air cleaner housing and the hose clamp on the throttle body.

2. Disconnect the electrical plug connection on the air flow sensor and remove the complete air cleaner assembly.

3. Relieve the drive belt at the tensioning pulley and remove the belt.

4. Disconnect the electrical plug connection on the vacuum switchover valve and unclip the switchover valve from the holder.

5. Undo the holder at the intake distributor(2 screws) and remove. Pay attention to the sealing ring (vacuum line for brake booster) when removing.

6. Undo left fastening screw (in direction of travel) and unscrew.

7. Undo right fastening screw (with deflection roller) by three turns. A gentle tap on the fastening screw loosens the threaded bushing in the generator arm (use aluminium mandrel). Unscrew fastening screw and remove with deflection roller.

8. The generator must be turned clockwise so that the swivel arm is near the crankcase and the holding arm projects beyond the fastening eye.

9. Carefully pull the generator back a little and undo the electrical connections, or press the plug connection to the generator housing, release (arrow A) and pull off. Pullout generator to the rear.

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Thank you very much Loren!

The guides I've found on the net never mentioned step 5. I have a fairly strong feeling that step is, by far, more important then one would think.

As for step 4, I merely loosened the bracket and put the bolts back into the manifold to ease the access as they where no longer in the way, might be beneficial to remove it all together, but I'll have to have another look.

I'm not so sure a "gentle tap" in step 7 is accurate either as I was unable to get it to "pop" in with some light-ish taps with a hammer and a piece of wood. I think I'll try to get some wd40 onto the threaded bushing, don't really know if it'll manage to penetrate into there, but it shouldn't hurt either I think.

I'll have to look into step 5 some more. If I'm unable to get this loose I'll probably have to flatbed it to PCO to get this sorted, which, for a simple alternator removal, is quite amazing :-p.

Thank you again.

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I just did this DIY alternator removal. Once the two 14 or 15 mm bolts were removed, I could rotate the alternator off of it's supports. I didn't really understand the mallet tapping because the alternator started

moving little by little until I got it clear from the two brackets.

I really had to look at what I was trying to do as far as "how to get it free". I kept turning it until I

could see the only way it was going to come out of there. It will come out towards you once you can visably

see what rotation is required.

From what I am reading, it sounds like it won't start rotating? I did use "Aerokroil" on the threaded bushing for the long bolt on the right. I don't think I really needed to do it.

I hope you get it free and moving because once you do that, a lot of wiggling and it will position itself to come forward and out.

I had to do this just for replacing the oil filler tube. I didn't need that "special splined" tool because

I did not have to remove the alternator pully. Good luck.

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Thank you both for the great tips. I'll probably have time tonight to have a go at it, last night I ran out of time and only made it to the car to add some wd40 to the "points of contact" between the engine and the alternator.

Rapewta; you're understanding it right, I'm unable to "turn" it around, but I'll try again :).

logray: do you mean I should use a pry bar between the intake and the alternator to get it free ?

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Oh man, just finished the job. Put about 10.000 light hammer taps on the long bolt, it didn't go back in all the way, but it must've gone that thousand of an inch further in. It was still basically stuck, but it did loosen just that much.

I did start tapping the lower part of the alternator with a wooden hammer, used a big screwdriver and silly amounts of time to get it irked out.

Finally did get it out, replaced the voltage regulator and got it into the basement to deal with the pressed fitting. Very easy to get it back into "default" position with a pipe on the backside in a vice. That did the trick.

At this point, I sort of figured out exactly how easy this job is if the bearing decides to properly pop back in after a few knocks during removal. Installation was stupidly easy with the bearing pressed in.

Thank you all for the help, your help was, well, very helpfull :D.

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Yea... you and a lot of patience and good advice got you through it. It is not easy for a first timer. I know.

You stuck with it and saved a ton of money if you'd taken (towed) it to the dealer. See... we can do anything if

we research it and put our skills to the test.

This website is a great tool to help us that are at the bottom of the food chain.

Glad you made it happen. Happy motoring.

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