I have found out what the extra radiator & fan are for. Its located on the passenger side just behind the fog light. 
05 CL65
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Cl65 AMG
Sorry still looking an explanation mini Radiator 05 CL65
I spotted a small radiator / fan, passenger side behind the head light / fog light area. Looks like coolant lines but I don't know what its designed to do. It would sure be nice to have a service manual. If anyone know could you fill me in. I am guessing a part of the intercooler/heat exchanger configuration. Sure an interesting car 
Last edited by driveability; Feb 2, 2012 at 01:09 AM.
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GL450
There are various coolers in there. You have the radiator, then the A/C heat exchanger, then the short one that's angled at the bottom is the IC heat exchanger. The ones off to the sides are normally oil coolers and the like.
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Cl65 AMG
Hey I do see the coolers mounted in front of the radiator and just below sits the oil cooler.
This unit stands alone on the passenger side of the car next to the intercooler pump, it has coolant lines and a nice size cooling fan attached.
I guess its part of the heat-exchanger intercooler system. One could surely understand the need to cool intake charge temp but not the engine coolant.
Hst, is it part of the heat-exchanger intercooler / turbo system ???
This unit stands alone on the passenger side of the car next to the intercooler pump, it has coolant lines and a nice size cooling fan attached.
I guess its part of the heat-exchanger intercooler system. One could surely understand the need to cool intake charge temp but not the engine coolant.
Hst, is it part of the heat-exchanger intercooler / turbo system ???
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Cl65 AMG
Thank you for the help, I am sure the mini radiator with a cooling fan stands out from the other coolers sandwiched around the main radiator. I am just looking for its purpose. I read online something about it on the newer 65 model and its described as part of the main cooling system. No mention of it being associated with the heat exchangers etc. If anyone has more info ...
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Cl65 AMG
The small radiator and fan located as stated is connected directly to the main radiator. It tees off the upper and lower radiator hose. I would think its a step above the high speed cooling fan in normal cars. This car is not normal and has a secondary radiator likely for help cooling at lower speeds. Seems to me the main radiator is being hammered by all the sandwiching other coolers. I don't think my pump was working. I did test it but it didn't work a few times on the bench without taping it with a blunt object. Maybe the car will run better !!!! Surely will since I never get on the throttle when the engine is cold. Anyway I'll take some pictures, don't have my lift installed yet so they will not likely be great...
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05,cl65;33ford3wc.
Heres a gess on the small radiator. If this small rad is as you describe maybe its used to cool the engine coolant in cold weather without utilizing the primary fan rad , as that action could delay trans cooling and other components that are still needing warm up.It would be nice to know its intended use before makeing any changes. Good luck with your project.
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Cl65 AMG
Here is a picture of the pump and pluming along with the mini radiator. I know the radiator has a temp switch screwed into it. That's a good thought of its purpose cold weather. Nice going. That would be interesting to test. Maybe the outside temp sensor placed in ice water ? Well I am now working on wiring the system. This was a bear to bleed ! I had to use a pump to get the coolant to move from the main sandwiched heat exchanger and then to the mini radiator 
. I did get it after a hour or so to set it up. I am going to instal temp sensors, maybe one on the mini radiator and one in the air charge at the throttle body.
. I did get it after a hour or so to set it up. I am going to instal temp sensors, maybe one on the mini radiator and one in the air charge at the throttle body.
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Cl65 AMG
I am finding it hard to bleed the new path. Having looked over the options re-routing the lines to keep the pump primed is best. At this point the pump is in-between the mini radiator and the factory IC heat sink. That's not a reliable road map. I'm going to have to add a reservoir and connect it directly to the pump inlet. I would like to have a "low fluid" circuit as well.
P.S. I sold my spare engine & transmission to a Mercedes Benz shop, there going to install it into a SL55. Interesting !!!!!!!!!!!!!!!!
P.S. I sold my spare engine & transmission to a Mercedes Benz shop, there going to install it into a SL55. Interesting !!!!!!!!!!!!!!!!
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From: medina ,ohio
05,cl65;33ford3wc.
I am finding it hard to bleed the new path. Having looked over the options re-routing the lines to keep the pump primed is best. At this point the pump is in-between the mini radiator and the factory IC heat sink. That's not a reliable road map. I'm going to have to add a reservoir and connect it directly to the pump inlet. I would like to have a "low fluid" circuit as well.
P.S. I sold my spare engine & transmission to a Mercedes Benz shop, there going to install it into a SL55. Interesting !!!!!!!!!!!!!!!!
P.S. I sold my spare engine & transmission to a Mercedes Benz shop, there going to install it into a SL55. Interesting !!!!!!!!!!!!!!!!
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Cl65 AMG
Your problem sounds typical of a system where the plumbing routeing constraints make for air locks. In the short term you may get the air out by losening the clamps to cause some leakage, if possible. I have a home retro fit hydronic heat system that after any invasive work wont start unless I bleed the air bubbles with vents in the trapped spots. As simple as this mercedes system is I still cant figure it out with what I can see by looking. I haven't seen a explaination of how merc allows for fluid expansion, I see two lines to the engine coolant resivoir, is one the ic,or do they do it all with that small caped junction in the rear as a closed system. In either case your resivoir may be usefull, it should be able to take the pressure of whatever that cap between the ics is. Hope this is some help, my cars put up for the winter so hard to check anything.
thanks for the input,
I have read that the two system join at the expansion tank, that doesn't seem to be correct. When I remove the small line (one of the two on the tank) and blow it comes out the connection I just exposed. there are two lines, the one that goes to the thermostat housing is most clearly part of the main cooling system. There must be another intersection in the maze of coolant lines
. I am going to look for that, oh maybe my gps will help ? LOL
