My factory pump for the SC cooling system recently went out so I bought a bosh 010 pump and decided I wanted to do Split cooling at the same time but since I’m cheap and didn’t want to buy a DTK heat exchanger or use a BMW power steering reservoir I decided to do my own kit, here’s what I used

1L aluminum coolant reservoir off amazon

2x ORB -6 to pipe thread fittings

2x pipe thread to 5/8” hose barbed fitting

Teflon tape for the pipe thread sections of the fittings

6ft of 5/8” radiator hose from autozone

5/8” to 5/8” straight barbed fitting

misc sizes of hose clamps and caps for factory coolant lines

so first I started by deciding where I wanted to mount the reservoir, decide behind the grill would be the best place I mounted it using zip ties for the time being

Then I removed the stock feed hose and capped it off with 5/8” rubber caps and hose clamps just to be extra safe

after that I got to putting on the correct fittings and running the hoses, bottom hose is a feed that goes directly to the pump, what I ended up having to do is cutting the stock molded line and putting a 5/8-5/8” fitting for the feed line ,I didn’t realize the pump was actually 3/4”. The return line comes straight off the heat exchanger and up to the top port on the reservoir. Routing the return line was a little tricky since I didn’t want it to get any kinks, what I did was run it up and behind the headlight, there’s a little area that goes up and back behind the grille there so I finagled it thru there and up to the new reservoir. For the S55 I had to cap off the factory bleed port to fully separate the system.




I filled it with Valvolines Mercedes coolant and bled the system and was good to go, sorry not to good at write ups but hopefully this helps some people out there if you have any questions feel free to ask

 

UPDATE: wife hit a rabbit shortly after doing this so I took the time to reroute one of the hoses, I bought a molded 90 degree hose, connected it to the HE and ran the hose straight up and then over to the Reservoir, I've also installed a 75mm FSP and even with the cooler being slightly bent on full throttle pull on a 100 degree day temps never exceeded 148 degrees Farenheight with stock coolers, will be getting a custom one installed shortly. will post an update once custom one is installed

 

Have you added the other heat exchanger? if so how did you route the tubes?

 

routing was more or less the same had to extend one of the hoses a bit as the new cooler is noticeably larger. It doesn't sit how I like some need to rework that so I can get a new bumper on the car

 

One thing I should note, when doing split cooling the way I did it's reccomended to cap off the airbleeder line coming off the IC return line or coolant will be pushed back into stock reservoir

 

But have you any @Budget Audio solutions for this car? That might be more interesting to many of us than split cooling. Just sayin...

maw

 

man I wish I did haha