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European 1974 350SLC ,'78 300CD& '80 300CD sold , '81 240D SWMBO's Car '84 300CD & Euro
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I see you didn't bother to clean the copper slip rings in the alternator and this can prevent charging .

To clean slack or remove the drive belt and use metal polish and a clean rag, turn the armature as you get golden color on the slip rings ..Another thing is : it's very easy to install the voltage regulator so the brushes are not sitting squarely on the slip rings .

HELLA is just as good as BOSCH , beware of any other brands, many are made in Germany but never quite reach 14 VDC .

If the bent is slipping it's east to tell by trying ti turn the alternator by the fan blades behind the pulley ~ if it turns with no sound it's slipping .

It you can force it to turn with a squeaking sound the belt isn't tight enough .

If you decide to replace it, ONLY a BOSCH branded & labeled rebuild will do ~ other companies fail to properly varnish the armature windings to they often fail .

The 65 ampere W123 alternator is only on the 1985 year models in the U.S.A. , again, BE WARY of whom you buy from .

Most breakers will have at least one 65 ampere W123 alternator, the BOSCH part number is : AL117X and it will ave that number on a sticker on the side of the alternator if it's a proper BOSCH rebuild .

Most places will sell you a generic one that look the same but at most is 55 amperes .
 

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European 1974 350SLC ,'78 300CD& '80 300CD sold , '81 240D SWMBO's Car '84 300CD & Euro
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980 Posts
No worries, no hurries .

When you're trying to remove the alternator be aware some of the 17MM ATF nuts on the face of the alternator are in fact WELDED IN PLACE and you'll need to undo the 1's from behind ~ seems really tough until you've done it a few times .

I highly recommend cleaning this area before you begin as these cars leak oil and have myriad nooks and crannie where dirt, oil and grease pack in .

There are cylindrical spacers between the sheet metal adjuster and alternator too, don't let them fall and roll away .
 

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European 1974 350SLC ,'78 300CD& '80 300CD sold , '81 240D SWMBO's Car '84 300CD & Euro
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980 Posts
Okay ;

Here's where it gets interesting -

Now I feel badly for tossing out all those good used 55 and 80 ampere alternators...

You don't have any parthaus' there ? seems kind of odd to me .

I buy parts in the U.K. and have them shipped to the U.S.A. on a regular basis.......
 

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European 1974 350SLC ,'78 300CD& '80 300CD sold , '81 240D SWMBO's Car '84 300CD & Euro
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980 Posts
Maybe Ken's Auto Spares ? .


Whatever you do, DO NOT let go of the old dead alternator until the new one is installed and working to your satisfaction .
 

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European 1974 350SLC ,'78 300CD& '80 300CD sold , '81 240D SWMBO's Car '84 300CD & Euro
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980 Posts
First thing is to check the valve gaps, they're almost certainly too close or zero lash .

After that we'll cover diagnosing a miss .
 

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European 1974 350SLC ,'78 300CD& '80 300CD sold , '81 240D SWMBO's Car '84 300CD & Euro
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980 Posts
There you go ~

Typically you adjust the valves and in 500 ~ 1000 miles a few will tihten up, do them again and it should be good for 12months or 12,000 miles .

Always do the basics first .
 
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