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2007 E220CDI, 1990 300E-24V, 1987 W124 3.6 AMG build 1993 E500 W124, 94 320CE, 1997 W140 S280
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Discussion Starter #1
Hi all I need to pull the alternator on my 2003 twin turbo S600. I watched a you tube video but that car was the non turbo version and the turbo ones have alot more hoses up front for the charge cooling system.

I am thinking of pulling the fan shroud, air pump and both the coolant tank + screenwash bottle in the hope I can use the same method. Has anyone else removed the alternator on the turbo models and how did you get that sucker out? TIA
 

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2007 E220CDI, 1990 300E-24V, 1987 W124 3.6 AMG build 1993 E500 W124, 94 320CE, 1997 W140 S280
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Discussion Starter #2
This is the video on youtube

 

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2006 S600
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I think removing the alternator is another one of those jobs that you do if you NEED to do it.

Are you sure there's something wrong? I'd want some evidence before rolling my sleeves up that far.

Incidentally, it may give you convenient access to the RHS diverter valve, which is worth replacing if you're in there.

Nick
 

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2007 E220CDI, 1990 300E-24V, 1987 W124 3.6 AMG build 1993 E500 W124, 94 320CE, 1997 W140 S280
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Discussion Starter #4
I think removing the alternator is another one of those jobs that you do if you NEED to do it.

Are you sure there's something wrong? I'd want some evidence before rolling my sleeves up that far.

Incidentally, it may give you convenient access to the RHS diverter valve, which is worth replacing if you're in there.

Nick
Hi Nick, I am pulling the alternator for several reasons. The main being that my S600 has an occasional charging / voltage issue which can be seen in the video below


At the moment I am replacing the engine mounts and fan pulleys so I am going to be already in there quite far doing this work so it makes sense so take the extra time and get the alternator out.

I have a pro rebuilder less than a mile from my home who is excellent and can fully rebuild most of my MB alternator with new slip rings, bearings, brushes + voltage regulators for about £50. Given the mileage and age of the alternator it will benefit from that and he will also test / repair the charging issue and let me know if it was the alternator. So I'll have a nice freshly rebuilt and warrantied alternator in the car and can look elsewhere for the charging issue if it wasnt the alternator.

It would be a pain if I had to spend hours again taking these same parts out to get to the alternator again. So all things considered I'm getting it rebuilt now
 

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2007 E220CDI, 1990 300E-24V, 1987 W124 3.6 AMG build 1993 E500 W124, 94 320CE, 1997 W140 S280
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Discussion Starter #5
And yes the diverter valves are going to be replaced. The evil ABC hose up front is already fresh new so it doesn't need done. Slight oil leak going to check the front crank oil seal whilst in there also
 

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2007 E220CDI, 1990 300E-24V, 1987 W124 3.6 AMG build 1993 E500 W124, 94 320CE, 1997 W140 S280
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Discussion Starter #6
Got it done. That was ridiculous- seriously the MB engineers must be evil to place hoses etc like they did. Entirely different to Clark's video since this car has engine oil cooler lines - right in front of the alternator. + a coolant hose and the charge cooler water steel and rubber lines. Radiator was drained obviously but the charge cooler circuit was not so those lines were not taken off.

Remove the air filter housing, right coil pack, washer bottle, cooling fan, serpentine belt, screenwash bottle and secondary air pump with bracket. Then fully remove the lower radiator coolant hose and you have to press the oil cooler hose downwards whilst wiggling the alternator out of its shell.

Then turn it in several positions and struggle to get it out past the charge cooler metal line. I mean that was TIGHT! Talking 1 or 2mm bigger and that alternator was not coming out. Phew - off to the rebuilder tomorrow to test it first and he will tell me good bad or indifferent. Then rebuild it anyway because I do not want to be pulling the alternator ever again pretty much

20191010_203820.jpg


20191010_211645.jpg
 

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S500 W220 SLK320 R170 C200 CDI W203 Peugeot Expert Van
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Nice write up and pix :)

Ask the rebuilder if the Warranty is Parts and Labour !! :D
 

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2007 E220CDI, 1990 300E-24V, 1987 W124 3.6 AMG build 1993 E500 W124, 94 320CE, 1997 W140 S280
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Discussion Starter #8
Nice write up and pix :)

Ask the rebuilder if the Warranty is Parts and Labour !! :D
I wish labour was Included! At 5+ hours R&R I doubt it very much 😛
 

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2007 E220CDI, 1990 300E-24V, 1987 W124 3.6 AMG build 1993 E500 W124, 94 320CE, 1997 W140 S280
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Discussion Starter #9
Attached is a useful document I found on these water cooled alternators. They are actually brushless units and diodes appear to be a common failure due to the heat at the front of the unit.

My rebuilder has the alternator now and he is to test the rectifier / diodes and VR for the fault. And my instruction is a new voltage regulator and bearings at a minimum whilst its apart. He seen my video and will test the diodes carefully, if in doubt at all they are to be replaced too. Not taking any chances given the inaccessible nature of the TTV12
 

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2009 E350 4M Avant Garde, My Mistress 2002 S600, Wife 2014 C300 4M Avant Garde with AMG
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if you search you will find a way to remove the alternator from the housing without removing the whole assembly
 

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2007 E220CDI, 1990 300E-24V, 1987 W124 3.6 AMG build 1993 E500 W124, 94 320CE, 1997 W140 S280
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Discussion Starter #11
if you search you will find a way to remove the alternator from the housing without removing the whole assembly
I have the alternator already removed. And I did only take the centre section out. Per the photo I posted above. I did not take the whole alternator and water jacket assembly off that would be much more difficult and time consuming
 

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2007 E220CDI, 1990 300E-24V, 1987 W124 3.6 AMG build 1993 E500 W124, 94 320CE, 1997 W140 S280
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Discussion Starter #12
So my S600 alternator was bad. The rectifier plate /diodes were faulty. My hunch was correct as I suspected as much.

He installed a new rectifier plate, new voltage regulator and new bearings so it's a fully refurbished and bench tested unit with warranty. £78. Result!! I cant even buy the parts myself for that much :cool:

PS if any UK members want his details PM me.
 

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Good result.

I was suspicious about the alternator as it had the usual W220 appetite for batteries. I spent ages measuring parasitic leak currents and pulling fuses. I never got anywhere, and presumed it must be the rectifier. However, it was never bad enough to do anything about.

My W221 has a separate battery JUST for engine starting, and that NEVER goes flat.

Nick
 

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2007 E220CDI, 1990 300E-24V, 1987 W124 3.6 AMG build 1993 E500 W124, 94 320CE, 1997 W140 S280
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Discussion Starter #14 (Edited)
Good result.

I was suspicious about the alternator as it had the usual W220 appetite for batteries. I spent ages measuring parasitic leak currents and pulling fuses. I never got anywhere, and presumed it must be the rectifier. However, it was never bad enough to do anything about.

My W221 has a separate battery JUST for engine starting, and that NEVER goes flat.

Nick
That's interesting that you also suspected something was up Nick! I havent owned it long enough to check battery drain but it seems OK in that regard.

Some more info for anyone in the future finding this thread - this is the old rectifer. Note the plastic rectifier bridge is melted and some plastic oozing out of it in places. He said the colour of the diodes is also abnormal showing overheating

20191016_183842.jpg
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20191016_183912.jpg


It was bench tested and a page given with the details. Its pulling 194 amps on his rig and he said it went over 200 amps at higher revs with ease so back in rude heath
 

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2007 E220CDI, 1990 300E-24V, 1987 W124 3.6 AMG build 1993 E500 W124, 94 320CE, 1997 W140 S280
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Discussion Starter #15
Before installing it I wanted to replicate the factory sealing. The rebuilder did use clear RTV underneath but not enough that it was seen around the edge as a solid bead.

So I used some clear high temp RTV and added another bead around the edge to ensure 100% sealing against atmospheric moisture - applied in the same manner as when new.

20191016_194143.jpg
20191016_194306.jpg


Bolts, edges and around the + terminal/ voltage regulator were all sealed like this tonight and will set for 24hrs before I re-fit the alternator
 
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