Installed a 143A alternator in my W124 (86-95E-class) - with photos - Page 4 - PeachParts Mercedes-Benz Forum

gsxr · #46 03-09-2011, 02:50 PM

JohnM. · #47 03-09-2011, 08:39 PM

Just put in a 120A S320 alternator a few months ago. Night and day difference. With my stock 65A alternator, my headlights used to dim slightly after 3000rpm, and at redline they were very very dim. After shifting the lights would go back to full brightness. Not very confidence inspiring.

abaddsm · #48 03-10-2011, 08:15 AM

Thanks for the info. The stock 94 E429 alternator is rated at 60-110 amps and I got it for $50 shipped on ebay! Nice wheels on that 91 300e. They look like Porsche turbo wheels in that small pic.

JohnM. · #49 03-10-2011, 08:58 PM

They are actually 17" replicas of the wheels found on the "C58 Brabus"

vstech · #50 11-07-2011, 10:55 AM

Quote:

Originally Posted by Gravedigger

Finally upgrades to 143 amp alternator. Ran a #2 ground to alternator bolt and 2 #6 to alternator output. and a # 10 to the for the small wire. All terminal ends are soldered on.

I can idle with headlights on high , fog lights on after-market driving lights on and my Fluke meter reads 13.98 volts. What an amazing upgrade.

... not sure of the need for this step.
the alternator is attached to a solid aluminum bracket, bolted to the block, and there is a large copper braid connecting the block to the body of the car.
this would eliminate the possibility of a voltage drop from the battery to the block through the body I suppose...
certainly if charging issues are happening, adding an additional ground to the alt frame could help. as could cleaning all the existing connections, and brackets.
Hmmm...

amosfella · #51 11-07-2011, 11:07 AM

Quote:

Originally Posted by vstech

... not sure of the need for this step.
the alternator is attached to a solid aluminum bracket, bolted to the block, and there is a large copper braid connecting the block to the body of the car.
this would eliminate the possibility of a voltage drop from the battery to the block through the body I suppose...
certainly if charging issues are happening, adding an additional ground to the alt frame could help. as could cleaning all the existing connections, and brackets.
Hmmm...

a quick buzz with a dremel tool and a steel brush on the mounting holes for the alternator is always a good thing... and a dab of dielectric grease. solved a number of charging problems for me....

lorainfurniture · #52 11-30-2011, 05:53 PM

I did this upgrade about a month ago thanks to gsxr's posts. I can finally turn my stereo up without my amp shutting down.

Just FYI, the wires are about 1 foot too long for my 89 300e. I just coiled it once near the battery.

bdtsr · #53 12-31-2011, 09:24 PM

Well after reading this thread way too many times and wanting to do the upgrade, I just purchased a 150amp unit on eBay for $100 shipped. Thanks to gsxr's pics, I was able to get the same part#. Now I have to wait for it to arrive. While waiting I will measure and make up the cables. I have tons of battery cable so that won't take long.

michakaveli · #54 01-01-2012, 09:26 PM

I sooooooo need this mod for my '97. The 65amp unit spec'd for my MY is pathetic.

Golden Ears · #55 04-17-2012, 12:31 PM

Thanks for the upgrade..I was wondering where this thread was... it is a no brainer. Years later..no issues.

cyberdyne · #56 11-09-2012, 03:45 AM

Is this upgrade needed in my 1992 400E or does it have a larger output alternator already?

The battery is also in the trunk. Does this change the cables required?

gsxr · #57 11-09-2012, 10:46 AM

Quote:

Originally Posted by cyberdyne

Is this upgrade needed in my 1992 400E or does it have a larger output alternator already?

The battery is also in the trunk. Does this change the cables required?

The 400E and 500E will have a 110A-120A alternator stock. If you have increased electrical loads (big stereo, overwatt lights, etc) then it would still be a good idea to upgrade to the 150A alternator.

The wiring on the 400E/500E is completely different. No wiring changes are necessary, although you can add an extra 4ga from the alternator to distribution block if you want... that's a bit overkill though.

JamesDean · #58 11-23-2012, 12:59 PM

I just scored this beasty on ebay for $40. Its the 143a unit. Listing said it was in perfect working condition and everything.

I plan on installing it on my 300D 2.5 and was curious if I would have to do any pulley swapping or re-clocking of the alternator.

lorainfurniture · #59 11-23-2012, 03:29 PM

on my 300e I had to swap the pulleys. it had a slightly different offset. I could not get it with the wrench, so I ran it up the street to the mechanic, and paid him 5 bucks to swap the pulleys with an impact wrench.

gsxr · #60 11-23-2012, 04:12 PM

You'll have to swap the pulley for sure, as the offset and diameter are different.

You can't tell if you need to re-clock until you compare the back of your 143A unit with the existing alternator & brackets. The new alternator doesn't need to have the terminals in the exact same location, they can be slightly different; as long as no brackets or pipes interfere with the wiring, AND the wiring is long enough to connect. Don't forget to replace the tiny stock B+ wires with larger cable similar to what is shown in my photos.