paulsbrookspe

Been dating someone with a 1999 230 SLK. Recently the alternator light is coming on, the local aftermarket MB repair shop wants about $900 to replace the alternator. I have no problem turning wrenches, but am a bit wary without a repair manual. Would like to be the hero here, but don't want to look like an idiot. So, a few questions:

1. How many components do I need to remove to get to the Alternator?
2. From what I have read, it is most likely the voltage regulator....thoughts?
3. Can the regulator be replaced without removing the alternator?

Any thoughts or advice will be appreciated.

Thanks!

MarcusF

The voltage regulator is a normal wear part. How normal? Mine has been changed twice and I keep a spare at home. The regulator costs $25 and the second you see a worn one next to a new one, you'll know why it's a normal wear part. This link may help.

On the off chance that you actually need an alternator, a good rebuilt one costs $300. If I needed an alternator, I'd take mine to my local starter/alternator rebuilder and have him rebuild mine. If I have mine rebuilt, the electrician will install a COMPLETE kit for under $100. The complete kit costs about $25 retail and it includes brushes, bearings, and diodes. No, a regulator isn't included. This is opposed to what most chain stores call a rebuild. Most chain stores contract out their alternator rebuilds to someone who rebuilds them for near nothing. They cost so little because they're not actually rebuilt. Whatever part is broken is typically replaced, and the other parts in the kit are saved. If it needs brushes, it gets brushes and a coat of paint. If it needs diodes, it gets diodes and paint. The same for bearings.

Some people can change the voltage regulator without removing the alternator. Removing the alternator is so simple, that I just take it out. To remove the alternator, remove the belt, unplug the wiring (careful not to short it), and remove the two bolts. It's pretty simple.

I hope that helps.

paulsbrookspe

thank you!

I took a peak under the hood, was pretty crowded. Do I go from below?

How do I release tension on the belt?

MarcusF

I accessed the alternator bolts from the top. I disconnected the electrical connections from below.

On a CLK430/55, the belt is loosened by turning the 17 mm bolt that is to the lower left of the tensioner pulley. I think you can access the bolt from underneath with the splash shield removed. I can access mine from either the top or the bottom.

paulsbrookspe

Thanks. The 230 is a tight engine compartment. My concern is/was it will be similar to my Volvo V90....you have to remove the steering pump (i.e. another component) to get to the alternator

alexyates

Hi,
You don't have to remove any other parts, just take the belt off, then undo the alternator from underneath, obviously you'll need to remove the engine cover from the underside. I did mine in no time, piece of cake.