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'08 E63 AMG Wagon. C280 (320) track/drift slag. Wife has CLK500 Convertible
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Discussion Starter #1 (Edited)
Well, it was bound to happen... It's a '92 500SE with almost a quarter million miles on the clock, so the original loom did pretty well!

All was well untill I took the car off the road for a month to fit the hydraulics (story to follow in a few weeks). I must have disturbed something, as the car would start-up and run OK until warm, then one bank would shut down. Not good. I figured it was the loom (as most people on here seem to have come across this common problem at one time or another), so took some covers off, and indeed, things were not looking good:



I enquired at the stealership for a new one - £532, which is just over $1000 US. Bugger that, I'll make my own...

Wire: £15
Heat shrink: £3
Electrical tape: £1
Tweezers: £1

Total cost: £20 (oh, and two evenings work!)

So, out with the old:


When I started to strip it down, I realized just how bad the original loom was - how was this working at all?!




Trying to figure out how to get all the connectors apart without breaking them was the biggest challenge, and the main connector to the body was the most awkward. It took an hour of very carefull prying to get all the glue/waterproofing out before I could pull the wires through enough to expose both sides of the connector.

Then there was the problem of getting each pin out. By pushing into the little slot each side of each pin with a modified (ground down) pair of tweezers, I could release each pin in turn:


Same method was used for the injector connectors:


 

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'08 E63 AMG Wagon. C280 (320) track/drift slag. Wife has CLK500 Convertible
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1,027 Posts
Discussion Starter #2 (Edited)
I carefully cut all the knackered wire from each connector, then soldered in new wire. Here are two injector pins with new wire:


And back together:


What better place to repair the loom than on a Mercedes v12 coffee table in my front room. Luckily, I have a very cool/understanding wife!


A couple of the connectors required some head scratching on how to get them appart. This 4-pin connector at the front on the engine was one of the more interesting ones!

Carefully cut around with the Dremmel:


New Wires soldered and in place:


And melted back together with the soldering iron:


Yeah, I know, not the neatest job, but it is strong, water tight and you really don't notice it back on the car.

OK, the MAF sensor... With thanks to one of v12Uberalles excellent "how-to's", I knew how to get this connector appart - unfortunately, I'm an impatient kind of chap, so cut it open with the dremmel!


It actually cleaned up nicely when put back together - honest!
 

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'08 E63 AMG Wagon. C280 (320) track/drift slag. Wife has CLK500 Convertible
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1,027 Posts
Discussion Starter #3 (Edited)
Loom now complete except main connector:


Just this little bunch to go:


Now I know I used all black wires, which may cause issues if I ever need to trace a fault, but I figured that there are only 22 wires to the main connector which would never take too long to trace, and one roll of black wire costs way less than 22 rolls of multi-coloured wire!

Main connector coming back together:


Completed loom!:


And back on the car, it's all looking fairly good:


Only made one small error - the wires to the front-of-engine connectors were very slightly too short (note to self: measure twice, cut once!), and would have been a little tight through the original ducting, so they now come out a couple of inches further up, but it still looks neat enough:


Pic of main connector installed with new cables:


On starting it up, I couldn't believe the difference! The engine has always wobbled slightly when idling - now it just stays completely solid. It seems to want to rev more more freely, and there is definately more power (especially low down torque). And even after sitting in traffic for a half hour, it just purrs contently! I guess the old loom had been on it's way out for a long time...
 

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1994 S420
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501 Posts
I like the Guiness on the table haha
 

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SEC 600 V12 2dr COUPE (RHD) One of the chosen few.
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2,233 Posts
Excelent job.. will you post a copy of it into the Kowledge base please..It will help others..I know you get these loom roblems when you dont run for a time.. I think its condensation and moisture due to lack of engine heat to keep things dry...
 

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F250 7.3TD Mercedes Benz W140 S600 1996 119k k's(sold), MB W124 300E 1989 261k k's(sold)
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464 Posts
A couple of evenings well spent, or saved. Impressive stuff. Did you make a map of the how all the wires came back to the main loom?

Now, have you put the old wires to any use? Weaved a lampshade perhaps ;) !
 

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1992 V12
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107 Posts
That's the way to save a whole lot of cash. I wish the S600 was that easy to do. I just redid my MAF re-wire last weekend.:thumbsup:
 

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'07 CLK350
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1,144 Posts
Awesome work! Thanks for sharing.

Question: Is that a V12 engine block holding up your coffee table? Way cool! :thumbsup:
 

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1996 S600
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200 Posts
Very high oogle factor in this DIY. Determination, improvisation, inspiration. You got it all. Still, don't know quite what to think about the 120 block under glass . . .
 

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Premium Member
1997 S600 (sold)
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4,660 Posts
Very nice work. I love your cost analysis. The tweezers were even really cheap. :) Hard to argue with that as justification for your efforts. Thanks for posting. Definitely inspirational.

Brett
 

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1914 Mercedes 28/95 hp, 83' 300SD, 93' S420, (three) 94' S420's, 95' S500 & 96' S600
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284 Posts
Outstanding innovation and inspiration to all.
Robert is in his corner applauding and yelling "WAY TO GO!"at top of his lungs. Fantastic to see this quality of work.

As suggestion... support your multiple conductor/pin in connectors at the area just before (50mm or so) each connector with tape or shrink sleeve as in "MB factory production harnesses". Reason: The harmonic vibration of the engine can/will cause premature failure at conductor to pin solder connection(s). Reared evidence in Failure analysis of vibration of "multiple soldered conductors" with and without circular support 50mm to 70mm of connector pin solder of multiple conductors.

Great to witness this type of work! Dietrich
 

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Seen as this has been bumped, can I ask... Is this do-able on a 1997 S420? Or is it only for the pre-96 engines?

PS: How did the move go? Hope your settling in well.
 

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'08 E63 AMG Wagon. C280 (320) track/drift slag. Wife has CLK500 Convertible
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1,027 Posts
Discussion Starter #20
Seen as this has been bumped, can I ask... Is this do-able on a 1997 S420? Or is it only for the pre-96 engines?

PS: How did the move go? Hope your settling in well.
Oh goodness, this really is bringing up an old thread! It was only a problem on pre-95 cars, so a '97 s420 will not have this issue.

We move to Germany next Tuesday. Boxes everywhere. Look forward to just being there! Thank you for your comment.
 
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