Getting Alternator Off? - PeachParts Mercedes-Benz Forum

ubertino · #1 09-26-2010, 07:38 PM

While wrenching on the engine I lost a 10mm wrench that fell behind the harmonic balancer part of the crank. I found it though (win) and have even been able to get some little claw hands and magnetic thingies to grab it. But. The round part of the wrench is stuck and it won't pull out at the very narrow angle that I have available. So the next best step is to remove the alternator to try and then reach behind that.

I've got the top rear 17mm nut off, and I've got the bottom 17mm nut about 1 inch out, with slow going unless I buy a ratcheting crescent wrench. I think that this is a purchase that will be made soon.

Other then these two 17mm bolts and the wiring bit in the back, what am I missing to get the alternator out? I see the nut that is used for changing the belt tension, is this going to be involved in removing the alternator? It's sorta loose right now, but that bottom bolt is a *****. Hanes says to remove the two bolts, take off the belts and wiring and call the job done, but there's not much for any kind of reach with that bottom bolt.

Help from those who've done this before?

qwerty · #2 09-26-2010, 07:48 PM

Quote:

Originally Posted by ubertino

The round part of the wrench is stuck and it won't pull out at the very narrow angle that I have available. So the next best step is to remove the alternator to try and then reach behind that.

There are two notches in the back of the balancer. Maybe you could move either the wrench or rotate the balancer. The wrench went in; there has to be a way for it to come out.

Quote:

Originally Posted by ubertino

Hanes says to remove the two bolts, take off the belts and wiring and call the job done, but there's not much for any kind of reach with that bottom bolt.

Due to excess length of the adjusting rod, you need to remove the alternator adjusting bracket in order to remove the alternator.

ubertino · #3 09-26-2010, 07:55 PM

Is there a special secret to removing that bracket? I think I've got a deep 27mm socket, I'm going to try and rotate the crank just a smidge.

The wrench fell in at one angle, and then twisted as it went in the rest of the way.

Yak · #4 09-26-2010, 09:31 PM

Pics of bracket in this thread: Alternator adjusting bolt

Yes, to remove the alternator you will need to remove the 90-degree adjuster bolt as it goes through the alternator. Loosen the nut on the rear, loosen the nut on the bottom, then unscrew the 10 mm (13, maybe?) nut and slide the 90-degree adjuster backwards. When it's completely unscrewed, remove the nut on the back, flip the thin threaded section out of the bracket "sleeve" and remove the bolt.

This seems like overkill to get a wrench out though. have you tried a coathanger or wire hook through the box end from above?

qwerty · #5 09-26-2010, 11:58 PM

Quote:

Originally Posted by Yak

Yes, to remove the alternator you will need to remove the 90-degree adjuster bolt as it goes through the alternator.

There is no need to do that.

ubertino · #6 09-27-2010, 12:26 AM

I spent three hours with two magnetic feelers and two little claw extenders, and a coat hanger with no luck. Tomorrow I'm going rotate the crank a bit and if that doesn't work then I'll finish taking off the alternator.

Qwert- if I don't remove the bolt, can the alternator still pull off?

vstech · #7 09-27-2010, 07:44 AM

to get the alternator out, you need to remove all three bolts from the back side of the alternator.
two pass through the alternator itself, one bolts the pivot point on the upper bracket to the block. it's up under the EGR assembly, so if you have a metal shield covering that, it's gonna be difficult seeing the bolt.
the bolt with the adjuster nut on it, only has a nut on the back side. it's not necessary to remove the nut, just loosen it well, so the alt is free.
get everything loose, and the belts off, and the alt just drops out.

toomany MBZ · #8 09-27-2010, 08:24 AM

To get my alt completely out of the car, I had to remove the bracket circled in the pic. As per qwerty's first response.

ubertino · #9 09-27-2010, 08:35 AM

It's getting daylight, time to start wrenching!

qwerty · #10 09-27-2010, 09:02 AM

Quote:

Originally Posted by toomany MBZ

To get my alt completely out of the car, I had to remove the bracket circled in the pic. As per qwerty's first response.

That isn't what I said. I said to remove the adjusting bracket, not the mounting bracket. (Removing the mounting bracket with the alternator in place would be quite a feat.)

Quote:

Originally Posted by vstech

to get the alternator out, you need to remove all three bolts from the back side of the alternator.

You are clearly confused.

qwerty · #11 09-27-2010, 09:23 AM

Quote:

Originally Posted by ubertino

Qwert- if I don't remove the bolt, can the alternator still pull off?

If you have the type of adjusting bolt with a threaded rod welded to the bolt head, you won't even be able to remove it unless you remove the adjusting bracket. But since you are not changing the alternator, there is no need to separate the alt from the adjusting bracket; just remove the alt with the bracket.

vstech · #12 09-27-2010, 09:37 AM

wahh. consufedd?

nahh. the upper bracket needs to be disconnected from the mount, and the other lower bolt in the alt, and the adjustment nut. all 3 on the back side of the alternator...
how am I confused?

toomany MBZ · #13 09-27-2010, 11:40 AM

Quote:

Originally Posted by qwerty

That isn't what I said. I said to remove the adjusting bracket, not the mounting bracket. (Removing the mounting bracket with the alternator in place would be quite a feat.)

Sorry, misunderstood.

I had to remove that circled bracket as the bolt closest to the engine didn't have enough room to come completely out, thereby hindering removal.

snookwhaler · #14 09-27-2010, 04:36 PM

Loosening the alternator belt adjuster, Removing the Lower alternator bolt and then the bolt at the back of the "adjusting bracket" let my alternator come out fairly quick. The alternator comes out with the adjusting bracket still attached to the alternator.

The first time I removed mine it was a serious PITA because the mounting bolts were worn almost in half and they were VERY difficult to get out. I got pictures of that whole fiasco on here somewhere. Be sure to inspect the mounting bolts and replace them if they are seriously worn.

I remember other members have had problems with the "welded nut" on the front of the adjusting bracket breaking loose. So, keep an eye out for that.

Now I can remove the alternator in about 15 minutes with no issues.

EDIT: Worn alternator bolt.