Help with Alternator DIY guide please!!
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Joined: Sep 2018
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1999 clk 430
Help with Alternator DIY guide please!!
Hi to all, had a problem with my 1999 clk 430, I was driving home when the red battery charge on the message center appear, went to autozone ( I know , I know) and they told me that my battery was faulty, I got a brand new battery and the car was fine for 2 days, on 3rd day driving back home ABS SRS lights came on and my car start to loose power until it died on the freeway, after towing my car back home I jump start the car to park it on my garage, car turn on and was able to park it, I did disconnect the battery positive terminal while it was on, the car didn't died but all the light were dimming and flickering, and the card sound like it was losing power, today I turn my car on and took it again to autozone they told me that it was my alternator, Im was looking in youtube for a video how to remove it, but couldn't find anything, I'm not mechanic savi but I was able to change the water pump on my BMW 540i 1997 and I'm thinking try to dot it myself, any advice will be appreciated, fuses or things to check before buying and alternator, and in case I need to change it please help me with a guide for beginners
Thanks in advance for taking your time reading this post
Thanks in advance for taking your time reading this post
Last edited by Ellioth Zombye; Sep 21, 2019 at 11:02 PM.
Super Member
Joined: Jan 2015
Posts: 920
Likes: 46
From: Worcestershire UK
W124 260E
You might be able to just replace the battery voltage regulator it sits in the rear part of the alternator . This is cheaper than replacing the alternator . .The battery will ,,if low on charge shut down the engine to save information loss from the computer
MBWorld Fanatic!
Joined: Nov 2001
Posts: 1,258
Likes: 209
From: Boston North Shore
2001 CLK320 Cabrio
Ellioth.......From you initial post, it appears that the alternator is not changing the battery.
While there can be other reasons for this, such as wiring connections, a common problem is that the graphite bushes in the voltage regulator wear down, such as they no longer make a connection to the alternators slip rings (see the videos below).
On your CLK430 it's probably going to necessary to remove the alternator to replace the regulator, but on the CLK320, I'm pretty sure the regulator can replaced from underneath (e.g. after just removing the splash plate), without removing the alternator.
During W208 production, MB used both Bosch and Valeo alternators, so you will need to determine which one your vehicle is equipped to purchase the correct part (e.g. using your VIN and checking the EPC (electronic parts catalog), dealership parts department or the label on the alternator.
While there can be other reasons for this, such as wiring connections, a common problem is that the graphite bushes in the voltage regulator wear down, such as they no longer make a connection to the alternators slip rings (see the videos below).
On your CLK430 it's probably going to necessary to remove the alternator to replace the regulator, but on the CLK320, I'm pretty sure the regulator can replaced from underneath (e.g. after just removing the splash plate), without removing the alternator.
During W208 production, MB used both Bosch and Valeo alternators, so you will need to determine which one your vehicle is equipped to purchase the correct part (e.g. using your VIN and checking the EPC (electronic parts catalog), dealership parts department or the label on the alternator.
Last edited by Serndipity; Sep 22, 2019 at 01:37 PM.
Thread Starter
Newbie
Joined: Sep 2018
Posts: 13
Likes: 0
1999 clk 430
Update with a Question
Ellioth.......FUrom you initial post, it appears that the alternator is not changing the battery.
While there can be other reasons for this, such as wiring connections, a common problem is that the graphite bushes in the voltage regulator wear down, such as they no longer make a connection to the alternators slip rings (see the videos below).
https://www.youtube.com/watch?v=uQP8...KrhrT&index=15
https://www.youtube.com/watch?v=VnKZ...KrhrT&index=22
On your CLK430 it's probably going to necessary to remove the alternator to replace the regulator, but on the CLK320, I'm pretty sure the regulator can replaced from underneath (e.g. after just removing the splash plate), without removing the alternator.
During W208 production, MB used both Bosch and Valeo alternators, so you will need to determine which one your vehicle is equipped to purchase the correct part (e.g. using your VIN and checking the EPC (electronic parts catalog), dealership parts department or the label on the alternator.
While there can be other reasons for this, such as wiring connections, a common problem is that the graphite bushes in the voltage regulator wear down, such as they no longer make a connection to the alternators slip rings (see the videos below).
https://www.youtube.com/watch?v=uQP8...KrhrT&index=15
https://www.youtube.com/watch?v=VnKZ...KrhrT&index=22
On your CLK430 it's probably going to necessary to remove the alternator to replace the regulator, but on the CLK320, I'm pretty sure the regulator can replaced from underneath (e.g. after just removing the splash plate), without removing the alternator.
During W208 production, MB used both Bosch and Valeo alternators, so you will need to determine which one your vehicle is equipped to purchase the correct part (e.g. using your VIN and checking the EPC (electronic parts catalog), dealership parts department or the label on the alternator.
I was able to removed the alternator and here some pics on my voltage regulator, still confused, should just change the voltage regulator or should I buy a new alternator, please help me to
e
MBWorld Fanatic!
Joined: Nov 2001
Posts: 1,258
Likes: 209
From: Boston North Shore
2001 CLK320 Cabrio
Ellioth......you have made a lot of great progress.
Your 1st picture, verifies that your vehicle had a Bosch alternator installed, showing both the OE MB and OEM Bosch part numbers.
As suspected, the next 2 pictures definitely show severely worn brushes and/or weak springs. Note that the brushes don't even make contact with the slip rings on the alternators rotating armature shaft.
The last picture shows the part number for alternator's voltage regulator, from which you'll be able to price and purchase a replacement voltage regulator vs a completely re-manufactured, which will also replace additional wear components (e.g. bearings, clutch pulleys, terminal hardware etc.).
Here is the Bosch part number (AL0766X) and typical price for a completely re-manufactured alternator. Note that there is a $100 core exchange and that you'll reuse the belt pulley from your current alternator.
https://www.fcpeuro.com/products/mer...-bosch-al0766x
You'll learn more regarding the specifics on the Bosch re-manufacturing process and benefits at:
https://www.boschautoparts.com/en/au...partID=AL0766X
