Khan 55

Good day my fellow W209 owners. From what I have read, the model 55 AMG is a little more unique compared to a C32 and some other models. I mention this because I have done some reading up on the forum and I see only on a C32 AMG do you require bumper removal. However another forum member has removed his bumper and mentioned it was easier to access the trans lines but he had done so to repaint his bumper. I might do the same as my poor bottom section has cracks and chips all over it now due to my dumbness of thinking the PDC would tell me if the car was far enough from the curb or not.

None the less, here goes.

I had just replaced, sometime during April of last year, my upper and lower coolant hoses as well as a new thermostat and a new radiator over flow bottle pressure cap. Not to mention, I also filled up my radiator with all new, possibly 4 or 5 liters of pure blue MB anti freeze and the remainder being water. Fast forward a year and few months later, I had done an engine oil service and air filter replacement 3 weeks ago. I also used the Mighty Vac tool to suck up some of me old steering fluid and replaced it with new Pentosin FUSCH's green fluid. Dumb me over filled it but I said I would drain it a bit later on when I had the time. So I get the car ready for my friend's son to use on his school year end function but to our surprise, the day of the function itself, horror struck. I was messaged and called numerous times only to be informed of steam being emitted from the front of my car or under the hood/bonnet. I was also sent 4second videos which didn't quite clearly indicate the problem to me but I thought, oh well, another coolant hose ruptured despite it being somewhat new. Will just have to call up agents and pay another ~$110 for the upper coolant main return hose.

So I go to collect the car after the ordeal and inspect the leak myself, sadly I find its the radiator that has developed a crack below the coolant return hose. I don't understand how this could have happened but anyway, I topped the expansion tank off with coolant and drove it slowly to my home. I parked it off and then confirmed again that it indeed is the radiator leaking.

Does anyone on here know why or have an idea as to why my radiator has cracked? The car has roughly 274 000km on it now. The radiator was replaced at some point as the BEHR sticker shows year of manufacture to be 2010 of November sometime. I don't have any oil and coolant mixing with the engine. I will check if there is heat coming inside the cabin area when I turn on the heater but when I had replaced the hoses, the tensioner, idlers, auxiliary belt as well as water pump all turned fine with no sounds or restriction when turning by hand. Anyway, I headed down to, well not a local MB dealership as they didn't have stock but drove for 40 minutes to the one which did have stock only to pay roughly $450 for a new radiator and 4 liters of blue coolant. Sadly the part inside the box is a Valeo brand that was manufactured in 2021.

Do I continue and use this part as I am sure the issues of coolant and ATF mixing with Valeo radiators should be a thing of the past and have now been addressed or can I return the radiator and try an obtain a BEHR one although I doubt I will as another parts store had some DBR or CBR brand for $150 so that's a no for me. If I use this Valeo radiator, should I fit an external oil cooler for the transmission and call it a day or just use it as normal? I was informed to do so by a gent whose father is an ex Mercedez Technician with regards to the external oil cooler.

I will upload photos using the WIS as a guide on how I go about replacing this so as to help others in future although this same repair is probably uploaded on Youtube.

Your input, comments, ideas are all welcome. Thanks to Rudeney for the WIS documents. Makes my life easier having to start up my PC at home, starting the WIS, then looking through for the relevant files.

Khan 55

Tools required:
a container/bowel for collecting old ATF and for collecting old coolant
shop rags or linen paper towel
cable ties/zip lock ties
a set of screw drivers, long, big, tiny and small but only flat head type (used for prying connectors as well as locking tabs on radiator)
set of o-ring pickers. There is an alternative name for it. (used for replacing o-rings, assist in prying off clamps on hoses, assist in lifting or maneuvering hood lock cable
size 10 spanner
size 10 socket and ratchet but the smaller the better. I used it 1/4" drive set for this exercise.
Side cutters and universal/combination pliers
set of torx driver sockets albeit you will need a T6 or T8 only.
new o-rings, 2 green ones for ATF lines and 2 black for coolant hoses
vegetable oil for lube
6 or 7 litres of MB Coolant. NB CLK55 AMG models use 12 litres of coolant so the remainder will be distilled water
1 litre of ATF depending how much you lose upon ATF line removal
2 new lower radiator cushion rubber mounts


First off, place a suitable container under the coolant drain plug and drain all the coolant after loosening or entirely removing the red plug under the radiator. It will be located on the passenger side front for EU cars and Driver side front for US vehicle models. I don't have a photo of this as I didn't want coolant spilling on my phone or touching my phone with the coolant after some leaked on my hands. Thereafter, open the expansion tank bottle to remove pressure from the system and allow excess coolant to drain as well. This will ensure there is very little to no coolant left in the radiator.
I then removed the bottom connector from the aircon FREON pressure sensor by pressing the tab gently and giving it a slight tug once the plug tab lever was above the notch on the sensor. I did the same for the fan connector at the bottom. Again I don't have photos pf these but will update the post with them after I snap a few.
I then moved on to the bottom coolant supply hose and pried the clip up so I could gently tug on the hose and get it out. Be mindful of the little coolant that will spill from here. Once it stopped dripping coolant, I used a linen paper to block the orifice. I then removed the lower ATF line by prying the clip up and then gently tugging on the line. I once again caught the old ATF in a bowel/container.
I then moved to the top of the engine bay and removed the front engine cover. I then removed the two screws that hole the front emblem and grill from the upper valence. You then need to check on either side of the grill where the rubber air guides are positioned and then slightly push the bumper outward so the locating dowel of the grill slides out of the slots in the bumper. You will then be able to remove the grill after detaching a connector from the sensor in the grill.
I then removed two bolts from the power steering lines that hold on to the frame in the front or front end cross member as depicted in the WIS and my photos taken. I then removed two lower bolts that cannot be seen but I have taken a photo of them once they were almost out that hold this front end cross member or PDC frame with its sensor to the lower crash bar of the bumper. Then remove the two connectors on the horn as well as the horn itself as this will aid in you being able to move the wiring harness out the way for the horn wires as well as the PDC sensor itself. Remove the PDC sensor connector as well. Be gentle as you don't want to break any of your MB connectors.
You then need to use a tiny flat screw driver with a clip removal tool to get to the 3 plastic retaining clips that hold the air duct section in place under the front end cross member or PDC frame. You will need to push the tiny flat screw driver from behind the clip under it so the tab can be pushed off its seat, then you can lift the retaining clip up from the front of its tab. Be extra gentle with these as I thought I had been but ended up breaking my last one that held my air inlet dam in place. Sadly this inlet dam or air cowl only has the retaining clips that can be purchased separately.
Then remove the 4 bolts, 2 on each hood lock mechanism. I started with the further one in my case the passenger side one where it would be your driver side one in the US. I used a o-ring picker to pry the hood latch cable out of the hood locks on both sides. I had to gently remove the plastic cover around them to do this. You will also need to detach the sensor connector on the one hood lock mechanism. I then detached the hood lock cable from under the plastic lock/positioning grommets that hold the cable under the front end frame. You will then be able to remove both hood locking mechanisms.
You then need to remove the 2 retaining pins that look like big black screws that help in locking the radiator in place. I used a torx socket this time a long with my trim removal tool to help lift it as I loosened it. Once both are out, you will need to then gently pry together using your index finger and thumb the retaining clip that seats under this pin. This retaining clip is what mounts in the rubber mount on either side of the radiator. I then got both out and my entire radiator and A/C condenser were loose or moving freely back and forth.

I then removed the 4 bolts that were positioned on either side of the lock mechanisms. You will now be able to remove the entire front end frame or PDC frame member from the front of the vehicle.
I then removed the air ducts from the front air dam or cowl. If you look inside them from the front, you will see there is a tab at the bottom that holds them in place. I gently pried them at the front whilst pulling them at the rear to get them off so I could gain access to the radiator fan.
You should now be left with a gaping front end as can be seen in my photo.
I then pried the radiator clamp at the top hose and gently tugged on the hose till it came off. I didn't battle as much as I did the last time when I replaced them as both my hoses are fairly new. The first time I removed this hose, I had been swearing all kinds of slurs to get it out the radiator as I tugged at it and wiggled it vigorously as well as sprayed some lubricant aid around it.
I then removed the top ATF line by prying the clamp holding it as well, then giving it a few gentle tugs aft and it popped out spilling some ATF. I once again used linen paper towels to block the lines and orifices.
Next step was getting the fan out. It is quite heavy for what it is but the housing of the fan is not. So be gentle with it or else you may have to replace your fan housing. It is held in by 4 positions on the radiator. The bottom two are sort of slots whilst the upper two have tabs that need to be depressed to get the fan and housing off its seat. NB to move the upper coolant hose out of place so you will have space later. I pulled up on the one side of the fan housing whilst depressing the tab on the radiator and had the one side lift up. I then done the same on the opposite side and had the entire fan and housing come straight up off its mounts on the back of the radiator housing. It is best to lift the entire unit upward whilst holding the sides rather than the center as opposed to holding the curve above the fan blade which may crack or worse. I have added photos of the tabs and their locating positions as well as a photo of the entire assembly so one can see where the mounts are or how to better deal with them personally.
I then moved on to detaching the A/C condenser from the radiator itself. I started at the top sections as you need to pry one part of it and then the top part of it which then allows the locating dowel of the radiator to slide out of the A/C condenser bracket. The condenser should then be free at the top. I then went under the car and gently pushed the radiator off the slots on the A/C as the radiator assembly has sort of like triangle fixtures that slot over this locking it in place. I was then able to remove the radiator by lifting it upward from its position.

The NEW RADIATOR will have the following:
all new clamps to lock both ATF lines as well as coolant hoses
a new drain or PET cog for the coolant

You will need to use the old rubber mounts or buy new ones. I replaced mine with new and have attached a photo of it.
You will also need to remove the square rubber mounts located in the top of the old radiator or get new ones however, I didn't see the need for this. I will admit, when you refit them to the new radiator, PLEASE ensure they are as flat as possible to prevent further issues when reinstalling everything. If not, this will affect the alignment of your front end member or PDC member when you are reinstalling the retaining clip for the radiator and its retaining pins.

You can then reinstall the radiator by locating it in its lower rubber mounts. I then reattached the A/C condenser to the radiator by ensuring the slots at bottom were mounted under the radiator triangle like mounting points and ensuring the tab and locating dowel at the top were positioned correctly. You will hear an audible snap once its in place.
I then fitted the lower coolant hose after inspecting my o-ring, taking note, my coolant hoses don't have more than 2000km on them so after they looked fine, I cleaned them and applied cooking/vegetable oil to them and reinserted the hose, thereafter locking the clamp in position.
I then installed the fan and housing unit, making sure to get all mounting points in place. There are 6 in total I think. One at bottom centre and one at centre top. Another 4 located on either side. I would recommend to pay special attention to locating the top centre first then getting the two upper outer ones pass the tabs and then the bottom outer two will slot into place. Then giving a gentle nudge will allow the entire fan and housing to locate at the bottom as well as enable the top to mount flush with the radiator mounting points for the fan and housing.
I then cleaned and inspected my upper radiator hose o-ring. Again, not more than 2000km on it and no signs of wear or bulging or cuts/burrs so I lubed it with vegetable/cooking oil and reinserted the hose, thereafter clicking the locking clamp in position.
PLEASE NOTE: I then did the same for both of my ATF lines. After I position the bottom line and then locked the clamp, I battled a bit to get the line itself to locate in the position tab of the radiator housing. So it might be better to first locate the line in the housing tab fixture and then place it into the hole for the oil cooler or vice versa. I prayed and used some persuasion and it managed to lock into the tab fixture without breaking anything.

Then fit the radiator retaining clip into the radiator upper rubber mounts.
I then placed the front end member or PDC member back in place. I fitted the hood cables to the hood lock mechanisms then inserted their bolts but didn't tighten it down until later when everything was centralized. I then reattached the hood cable to the under mounting plastic fixtures on the front end member. I also inserted the 4 bolts that mount this entire member on to the top of the main body frame but again, not torqued down as to help centralize it later.
I then fitted the two bolts at the front of the crash bar to the bottom of the front end member followed by the two bolts for the P/S cooling line and its mounting fixtures.
I then placed the radiator retaining pins in place. I then reattached the horn and it's two electrical connectors as well as the PDC sensor connector. I then reattached the bottom A/C pressure connector as well as the fan connector.
I then reattached the air ducts to the main air dam cowl. If your top fixtures aint broken like mine, you can now install the 3 retaining clips to hold the air dam in place under the front end member.
You can now also mount the special plastic fixtures for your electrical lines that you would have removed earlier to get the front end member off. There will be 2 for the lines on the horn and PDC sensor as well as grill sensor and another that would hold the top coolant bleed line that feeds the expansion tank.
You can then fill the radiator with new fluid as per the instructions on the agents fluid. I have bought 6 litres of anti freeze. Our radiator specifications mentions 12 liters of coolant.
You will also need to top up the ATF. I am conducting an ATF service whilst this scenario dawned on me so I will make sure to follow the WIS instructions using dip stick and measuring ATF level when engine is cold and then rechecking when ATF temp is at a certain point then add as necessary. I didn't really lose more than 500ml from the ATF cooler in the radiator. Surprising and I decided to conduct the ATF service just in case I would have any coolant mixing.
Thank the Lord, when I drained my trans, there was not alot of ATF, roughly 3 litres and its all reddish in colour. So it seems my ATF and coolant did not mix. I will remove the trans sump and clean the magnet as well as replace the filter and sump gasket and collect the remainder of the fluid from the trans sump pan into my container with the other 3 litres so I can refill the same amount. Albeit conducting the correct WIS checks thereafter to ensure correct ATF level.

I hope this write up helps, but as mentioned, there are probably videos online of this already by today's day and age.
I would rate this on a difficulty of 1-10, probably a 5 for myself. I didn't battle much with anything taking into consideration I am a qualified mechanic and I have already done my coolant hoses and thermostat early last year. This exercise is just time consuming but well worth it in the end.

Drain coolant here



retaining clip on air duct to front end member

2 mounting screws for grill to front end member

lower bolt for P/S line to front end member

2 lower bolts for front end member to crash bar

upper bolt for P/S line to front end member

Bottom coolant hose removed

Upper radiator to A/C mounting tabs

Upper radiator to A/C mounting tabs

Lower rubber mount and tab for A/C to radiator

Lower radiator to A/C mounting point

removal of hood lock mechanism & special attention to plastic housing tabs

special attention to plastic housing tabs

bottom of plastic housing tab on hood lock mechanism

plastic housing mount on hood lock mechanism

Use o-ring picker to pry hood cable from lock mechanism

Use o-ring picker to remove hood cable from lock mechanism

Radiator retaining pin and clamp

radiator retaining clamp

radiator retaining clamp

Front end member removed

Upper center mount of radiator fan housing

Side mount of radiator fan housing

Side mount of radiator fan housing and upper radiator hose removed

Lower slot or mounting stay for radiator fan housing

Lower slot or mounting stay for radiator fan housing

Bottom center mount of radiator fan housing

fan and housing removed. Take note of mounting points



Remove upper radiator bushing/mounting

Using a pick, slot it at an angle, push down and then turn pick straight, then gently pull up whilst wiggling to get bush out. Alternate slots for better results

Upper radiator bush removed

Assistance from pick to get bush out

Lower mounting bush, 2 needed

Replacement radiator

Take note of mounting stays. Remove blank off plugs for ATF cooler

Take note of mounting stays

The installation photos will be the reverse of removal. Be gentle as your parts might be old. If you are only replacing radiator, it would be best practice to replace coolant hoses as well as thermostat. I am budgeting to replacing my water pump as well after this failure.

Thanks to previous post dealt with on this forum that helped me out with this task.

cm60k

Amazing write up bro..

-;-ZAYED-;-

Khan 55

Shukran brother Zayed . Was happy with the out come. Just need to order some of those stupid plastic mounts for the electrical cabling from agents and possibly another liter of coolant. Had a very sore lower back after yesterday as majority of the time I spent trying to position the new radiator in between the side member chassis legs, then the same with the fan and housing, then at one point the darn thing got stuck and the top mount wasn't in. Had some difficulty trying to get it free again but I managed eventually.
Will see during the course of the week if I can drop the transmission sump and do all necessary work to have it ready before next weekend. Lucky this aint my daily ride.

AMGForce

Hi all I was wondering if someone can please assist me. I have an engine cooling fan issue the part no. Is A2035001093 but this is coming up 6-700 just for the part. Is there any other radiator fan I could posisbibly use a clk320 or any other part numbers which will work I know mines a 850w but the rest c209 come up as 600w even AUTODOC comes up with different part numbers but still shows as compatible