Topic: W124 Clean up

For those of you that have run the w124.  All the wiring on the inside that runs in the plastic raceways..  did you leave it as is in the chase ways or or did you tie wrap it down??   So many wires that go to the trunk!!!  I'm sure I'll have 100 more before I'm done, but thanks for the advice!

Team Captain - Questionable Compression Racing
1992 Merc-B 400E "Benz Green Machine"
total noobs....

Re: W124 Clean up

We run a W201, so similar vintage wiring. The W201 used a ton of vacuum lines for the windows and locks, so those were all removed completely. Most of the wiring going into the trunk is for lighting and the stereo (and the fuel pump!). I would not remove this, even if you have it disconnected because you never know when you might need a spare.

We removed all of the plastic raceways and have tie wrapped everything FAA-spec, every 4". We relocated the battery to the trunk (get a length of 00ga. cable from a BMW at the junkyard) and all of the wiring that runs to the trunk is tie wrapped to this cable in one big bundle.

If you can find the W124 electrical diagrams, take the time to print them and mark which wires you don't need. Then go one-by-one and remove that which you don't need and label that which you do. It's time consuming but if done right you'll end up with a pile of wiring that you don't need, and a much more streamlined car. We spent a lot of time doing this, but it's easy to troubleshoot issues because we have only the bare minimum.

One important lesson we learned the hard way: the vehicle ground doesn't work the same once you install a cage, remove bodywork, and relocate the battery. If you remove the OEM MB switchgear and replace with your own toggle switches and wiring, you'll want to be attentive to this. This means that relays might not reliably pick up, or current might be higher in places giving hot connections. We solved this by running two 16ga. wires in parallel from the battery negative terminal to a terminal block on the passenger side bulkhead. This is where all of our ground connections are tied to.

Feel free to ask anything, we've been at it for a few years and don't mind sharing our lessons learned.

Giubo Grabbers #190 - 91 Mercedes 190E
2016 CMP Fall South "Heroic Fix" Winner

Re: W124 Clean up

Thanks!!!  One bonus having the M119 is that the battery is already in the trunk!!   I only have a couple of toggles that I am going to add for race number 1, is one to manually activate the twin cooling fans and one for an LED light bar.  I'll probably add more switches once things start to break.

Thank you so much for the advice.   I will take you up on your offer for help!!

Brad

Team Captain - Questionable Compression Racing
1992 Merc-B 400E "Benz Green Machine"
total noobs....

Re: W124 Clean up

On the other end, I left all the wiring alone and in the raceways in our W140. I keep eyeing how much wiring is down there, but keep thinking that I don't want to do battle with solving why suddenly the brake lights don't work and it won't rev over 1500. Early 90s module connectivity is, um, special. I think either approach is valid. I'd like to run standalone EFI and get rid of everything else, but the dyno time needed to get that running just so, ain't cheap.

Tradewinds Tribesmen Racing (The road goes on forever…)
#289 1984 Corvette Z51 #124 1984 944 #110 2002 Passat
Gone but not forgotten, #427-Hong Kong Cavaliers Benz S500
IOE (Humber!) Hell on Wheels (Jaguar)

Re: W124 Clean up

You have the same fears that I have.   Every time I pull out a light bulb I check and see if the car will start rev and shift. 

Let me ask you guys a second question, since I have you here.  What items did you find most valuable to sell.  The interior in my car was roached from having window that was down except for the wood which I saved.  Any other hi-val items to give me a little to work with?

Thanks!!!

Team Captain - Questionable Compression Racing
1992 Merc-B 400E "Benz Green Machine"
total noobs....

Re: W124 Clean up

A guy gave me $400 for the heated power seats. That, and I got $50 for the sunroof assembly. Actually, I got $250 for the sunroof but misquoted shipping ate $200 of it. I would have made good money on the headlight assemblies, but they were already gone- being partially parted out is how you got a good running s500 for $700 in 2011... It would be easier now.

Tradewinds Tribesmen Racing (The road goes on forever…)
#289 1984 Corvette Z51 #124 1984 944 #110 2002 Passat
Gone but not forgotten, #427-Hong Kong Cavaliers Benz S500
IOE (Humber!) Hell on Wheels (Jaguar)

Re: W124 Clean up

thebeedubya wrote:

I only have a couple of toggles that I am going to add for race number 1, is one to manually activate the twin cooling fans

This is a joke amongst our team because the twin cooling fans are an emergency cooling function for the engine, yet in our case they were activated by the climate control system. Why you'd have a non-essential system doing essential work is beyond me...

Be aware, the twin fans put a lot of electrical load on the motor. We've learned that we don't need them at all during the race to cool the engine and just have the drivers turn them on when exiting the track or in the pits. Mercedes built quite a bit of margin into their cooling systems.

Giubo Grabbers #190 - 91 Mercedes 190E
2016 CMP Fall South "Heroic Fix" Winner

Re: W124 Clean up

Did you leave the belt fan??  We were planning on deleting it...

Team Captain - Questionable Compression Racing
1992 Merc-B 400E "Benz Green Machine"
total noobs....

Re: W124 Clean up

thebeedubya wrote:

Did you leave the belt fan??  We were planning on deleting it...

Have had the engine get kinda warm during some races. Have never been able to convince myself that taking a fan off is a good idea. I just run the one remaining condenser fan all the time, the car has a 140 amp alternator (only have one fan because the other one quit) and can handle the load without incident. Trying to get drivers to remember to switch th fan on at appropriate intervals seems chancy.

Tradewinds Tribesmen Racing (The road goes on forever…)
#289 1984 Corvette Z51 #124 1984 944 #110 2002 Passat
Gone but not forgotten, #427-Hong Kong Cavaliers Benz S500
IOE (Humber!) Hell on Wheels (Jaguar)

Re: W124 Clean up

thebeedubya wrote:

Did you leave the belt fan??  We were planning on deleting it...

We removed it but our fan clutch was also failed when we bought the car so it was worthless. During normal racing we run without any fans. We've never had any trouble with also having the trans cooler loop in the radiator, but are splitting that out for next race to give more margin. We also removed one foglamp and cut louvers into the hood so we have a constant flow of fresh air cooling the engine bay.

If your car is a V8, things may be different. The M103/4 inline sixes I think use the same radiator as the larger motors.

Giubo Grabbers #190 - 91 Mercedes 190E
2016 CMP Fall South "Heroic Fix" Winner