I set out to upgrade the alternator as mine had died.

Getting at the alternator wasn't too difficult.
Start by removing the lower cover, then remove the RennTech anti-roll bar.
Loosen the belt tensioner and remove the belt.
remove the upper and lower bolts on the alternator and remove the wires on the rear of the alternator. (8mm and 13mm)

Upon inspection the wires were fried ! Insulation missing. The 8 gauge wire from the alternator was ok but the plastic boot was brittle. The insulation was gone off the D wire and it was exposed in a few areas.

There were 2 other wires sharing the same sheath, one to the oil pressure sensor and the other to a low oil sensor (I think).
Both were brittle, missing insulation and somewhat loose. I am surprised I wasn't having more problems with shorts...probably would if the sending unit would have triggered.

I was in the process of removing the wiring as I intend on upgrading to 1/0 cable and traced it back to the starter heat shield (so I removed it - 3 10mm bolts).

I am curious how the wire runs down to the starter, I removed the heat shield but the wire seems to be held in place pretty well....any tips on how to remove it?
How does the starter wire up? it appears to be part of the same cable run.
I'll post some pix soon as I can.

I am concerned about the heat levels these things may encounter, I want to add some protection on all wires if possible.

Thanks for any help!

__________________
Bryan Harter
1992 500E Smoke Silver
2002 CLK55 AMG Cab Silver/Black
2001 Harley Fatboy - Pearl White
2004 F150 FX4 Silver/Grey
1969 GTO Liberty Blue
1956 F100 Black

There was an un sheathed area between the clamp at the starter and the band at the end where the wires are all exposed completely.
I didn't get a good pic but will post one later.

Attached Thumbnails

       

__________________
Bryan Harter
1992 500E Smoke Silver
2002 CLK55 AMG Cab Silver/Black
2001 Harley Fatboy - Pearl White
2004 F150 FX4 Silver/Grey
1969 GTO Liberty Blue
1956 F100 Black

Hey Bryan, How much did that Alternator set you back for. What were the symptoms that it was going out.

Lastly what do you think this is

On my 93 500E, I sometimes feel a pulsing from the engine when driving the car at normal speed. It feels like a really huge load is being placed on and then removed off the engine, sort of like whne the AC compressor kicks on and off...but it happens when the AC is off also. Might it be drag from the Alternator??....What are some other options....

__________________
Regards,

Albert
aldedmon@yahoo.com

I've got the 150A alternator on both my 300D and E500. Cost for a used one is usually $100-$150 plus S&H and installation. You need to use your existing pulley. I posted a detailed writeup, including voltage and current measurements, in a thread a couple of years ago:

Installed a 143A alternator in my W124 (86-95E-class) - with photos

Your intermittent drag probably is not the alternator. Maybe the air (smog) pump? Hard to say...

__________________
Dave
Boise, ID
Check out my website photos, documents, and movies!

I recently did an alternator swap because mine went out. I put in the 143A one as described in the other thread from a later model S class. after a few months, it died. I went to the alternator shop, and he told me those ones are junk, because they have ann internal regulator that can;t be changed. so he took the regular alternator that fits my car, and rebuilt it to 150A for $80.00 (Because I had alredy paid $150 for the previous alternator a few months beforehand. )

So now I have the correct alternator for my car but at 150 Amps instead of the 70 or 80 it was, with the changeable regulator.

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'92 300CE - Sold
2004 C240 - 744 - C7 Wheels - Android Radio
2002 C320 - 816 - Sport Wagon

Say WHAT? All the factory alternators, up to the 143/150A units, have replaceable internal regulators. Both of my 150A units have replaceable regulators behind the plastic rear cover (the regulator is attached with two Phillips screws). Maybe he meant something else...

all I know is he said that he gets those in so often because they fail often.

So my older style alternator is back on the car but redone to 150A. works great for me...

The guy was a whiz, he had it done in 2 hours, including R&R of the alternator.

I think some of them may not have the regulator being changeable... and thats what I had gotten originally.

Alon

__________________
'92 300CE - Sold
2004 C240 - 744 - C7 Wheels - Android Radio
2002 C320 - 816 - Sport Wagon

We have a shop here in Portland, called Faulkner Auto Electric, that is Bosch authorized and can re-do alternators to a larger capacity.

I had a stock 50-amp 300SEL 6.3 alternator (this is for a car that is nigh 40 years old) re-done to 90 amps using Bosch parts.... It cost $200 out the door, no sales tax. This for a friend in Germany, who installed electric aux fans underhood to alleviate heat for the 6.3 engine compartment.

I may this spring have the stock E500 alternator reworked by these folks to max it out as well (OEM parts). Less hassle than dealing with one from another car. Bolt-in mod.

Faulkner is about 2 miles from my house in NW Portland. Looks like a place out of the 1940s, but these places are the best because they do honest work, unlike so many places you see these days... When you go in there you see finished jobs ranging from Model Ts to Hudson Hornets to 60s Muscle cars to VW Bug generators to late-model AMG cars...

Faulkner Automotive Electric
(503) 227-3567
(800) 547-0361
1831 NW 28th Ave
Portland, OR 97210

Cheers,
Gerry

the company is the guy my mechanic has all the alternators done at. it is in northridge area, off of reseda and parthenia area.

eagle auto electric is what it is called I believe.

The shop had alternator and starter parts all over, but the guy knew his stuff and was very nice and willing to work out a deal.

overall my alternator cost me like $225.00 total that is after buying the bigger alternator originally for like $145.00, then after it failed in a few months, having him rework an original w124 alternator to 150 amp for $80.00 (that being that he credited me for the failed unit.

I am thinking it may be time for a new battery, though my blue top optima has been great for the last 5 years, and has never left me with a problem, even when my alternator went out, it still provided enough juice to get me home, where I charged it and was able to get to my mechanic and the alternator guy and it was all good for me. I feel it may be getting a bit tired finally, but it holds charge well and works great.

I have been looking into one of those other brands like SVG, Odyssey or Hawking batteries, which are geared towards high end car audio. but I love optima, great battery but pricey, but mine has more than paid for itself.

I do remember seeing a while back some batteries but I forget the name, where they were half the size of a standard group 34 battery, but had twice the power, and one could fit 2 of them easily in the battery tray designed for one group 34 battery. I have been searchign around trying to find the name, because I would like to buy 2 of them, to put in my car one to runt he car the other for my sound system.

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'92 300CE - Sold
2004 C240 - 744 - C7 Wheels - Android Radio
2002 C320 - 816 - Sport Wagon

Yep, my 143 and 150 amp BOSCH alternator for a 1999 S-class have user replaceable regulators.

In fact, I changed my out myself when I did the upgrade.

Mine has lasted over 3-years.

:-) neil