C55 Alternator Replacement
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2005 C55
C55 Alternator Replacement
I found some DIY and couldn't believe you had to remove the radiator fan shroud to replace the Alternator. Reminding you I'm talking about a 2005 C55 not a C32 which I assume would be relatively easy compared to this.
So just wanted to say, "Yes" that is the only way. There simply isn't room to drop the alternator out the bottom. Imagine a motor mount and if you haven't done one of those you have no clue. The alternator is twice that. It will be a messy job too because you'll drain your radiator and remove hoses to your overflow tank. It will a tuff tug to get your fan shroud out as well, you need 4 thumbs (I used a feeler gauge on one side in lieu of not having more thumbs). I found the plastic pieces, clips and such, would break with the slightest provocation, dealer parts only too. Be prepared to replace your idler pulley and belt. I got a replacement Alternator from PepBoys for about $177 but you can get them from AutoZone too or likely else where of course this is after you leave your old one which is worth about $75. And YES, it won't come with a pulley so be sure you take the one off your core. I have some receipts laying around if you need p/n
I could have just replaced the regulator on the back of the alternator but to be honest, considering the amount of work involved to R&R I decided not to take the chance the DIODES which cannot be replaced (that I know of) were bad. It was tested and was BAD. So decided to replace the whole thing. I didn't do a write up here thinking someone else already has, if not if you catch me within a few days I still may remember things and might have a picture or two.
I have two words to describe it "PITA" & "MESSY". Plan for about 3 hours tear-down taking your time not to damage things like the radiator. I think I put it back together in about 1.5 hours. Not sure how much I saved by not taking it to the dealer. I read somewhere that the alternator from a dealer was around $600. I assume this was just the part, not labor. Nothing like the feel of antifreeze on your hands too, which reminds me - buy brake fluid cleaner, you'll need it.
To be honest, maybe I'm cheap, but I would do this again now that I know how. And though this may sound weird, it seems to run better. Dyno mode shows 14+ volts, before was up and down somewhere between 12 and 13.5.
So just wanted to say, "Yes" that is the only way. There simply isn't room to drop the alternator out the bottom. Imagine a motor mount and if you haven't done one of those you have no clue. The alternator is twice that. It will be a messy job too because you'll drain your radiator and remove hoses to your overflow tank. It will a tuff tug to get your fan shroud out as well, you need 4 thumbs (I used a feeler gauge on one side in lieu of not having more thumbs). I found the plastic pieces, clips and such, would break with the slightest provocation, dealer parts only too. Be prepared to replace your idler pulley and belt. I got a replacement Alternator from PepBoys for about $177 but you can get them from AutoZone too or likely else where of course this is after you leave your old one which is worth about $75. And YES, it won't come with a pulley so be sure you take the one off your core. I have some receipts laying around if you need p/n
I could have just replaced the regulator on the back of the alternator but to be honest, considering the amount of work involved to R&R I decided not to take the chance the DIODES which cannot be replaced (that I know of) were bad. It was tested and was BAD. So decided to replace the whole thing. I didn't do a write up here thinking someone else already has, if not if you catch me within a few days I still may remember things and might have a picture or two.
I have two words to describe it "PITA" & "MESSY". Plan for about 3 hours tear-down taking your time not to damage things like the radiator. I think I put it back together in about 1.5 hours. Not sure how much I saved by not taking it to the dealer. I read somewhere that the alternator from a dealer was around $600. I assume this was just the part, not labor. Nothing like the feel of antifreeze on your hands too, which reminds me - buy brake fluid cleaner, you'll need it.
To be honest, maybe I'm cheap, but I would do this again now that I know how. And though this may sound weird, it seems to run better. Dyno mode shows 14+ volts, before was up and down somewhere between 12 and 13.5.
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1999 E320 4matic Wagon, 2005 C55 AMG - sold, 1998 VW Jetta TDI - sold, 2006 C230 Sport - Totaled :(
Were you trying to pull the alternator out from the top of the car? According to the STAR manual you are supposed to pull it out through the bottom...
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C55 AMG, 300D-T & Karmann Ghia
Effe and I...................1
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2005 C55
From the top. Unless you can lift the engine significantly to make clearance, I don't see how you could get it out from the bottom. I just replaced my leaking motor mounts a month ago and didn't want to disturb any of that again. I personally don't like raising the engine in the first place because even if you are watching closely, you end up stretching a hose or loom unknowingly. Just my personal preference. I don't know who wrote the star manual but perhaps they figured the C55 would be the same as a C32 or perhaps they didn't actually try it.
MBWorld Fanatic!
Joined: Sep 2010
Posts: 1,545
Likes: 6
From: Washington DC
1999 E320 4matic Wagon, 2005 C55 AMG - sold, 1998 VW Jetta TDI - sold, 2006 C230 Sport - Totaled :(
From the top. Unless you can lift the engine significantly to make clearance, I don't see how you could get it out from the bottom. I just replaced my leaking motor mounts a month ago and didn't want to disturb any of that again. I personally don't like raising the engine in the first place because even if you are watching closely, you end up stretching a hose or loom unknowingly. Just my personal preference. I don't know who wrote the star manual but perhaps they figured the C55 would be the same as a C32 or perhaps they didn't actually try it.
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2005 C55
One more thing to add since I've been driving around and noticed. Before the alternator replacement, my A/C would simply just stop and I would have to fiddle around with the controls like pressing Auto on/off, turning the knobs on/off to get it to come back. Usually took about 30 secs and on a hot day that seems like eternity. That problem has gone a way! --- Also, at idle before replacing the alternator, it seemed a bit rough. I figured it was time for wires since I had already replaced all 16 plugs. But that too has gone away so just guessing perhaps the VR was marginal for some time. Perhaps noisy in the sense that it wasn't delivering pure DC but perhaps noisy DC. Like I said, just guessing. These changes could also be due to the fact I disconnected the battery but to be honest I've done that before without seeing these changes. Anyhow, for what it is worth.
Next up, A/C Blower Motor -- it's making a ticking noise so need to see if it is rubbing on something in there.
Next up, A/C Blower Motor -- it's making a ticking noise so need to see if it is rubbing on something in there.
