Originally Posted by jumpman726

If you just need to top off some coolant and you don't want to buy the Mercedes concentrate coolant from the dealer and then have to mix it with distilled water you can get this ready to use PEAK OE coolant at Auto Zone (part# PEBB53) for $20. It's BLUE just like the original color in W212's and according to the label it's designed for Mercedes cars pre-2014. (FYI, the spec on the Autozone website for the boiling point temp is wrong. On the actual container it says the boiling point is 265 degrees (F), which is what Mercedes recommends).

https://www.autozone.com/antifreeze-...20593_715269_0

Originally Posted by superangrypenguin

And this is why I don't buy used cars..

Originally Posted by Vilem

Geniue radiator petcock fits my W212 2010 4 matic , originally for Chrysler and Jeep. Original was Valeo.

As the winter is comming here, I really re-considered possible consequences if my previous solution fails for ex. on a highway. Undesired. Engine execution.Scepticism of some of you was definetelly right. So here it is : I got it shipped superfast, fair price and the resoult is absolutly amazing... Not a single drop since the instalation. Vibration resistant radiator **** drainnplug E class W212 with Chrysler sign on the box. What the hack! . In fact, this one is much more solid with masive knob handle... great. Factory quality now. ..Big thanx to the producer. Rare stuff. Took me weeks to google it out but finally got it down.Every mechanic in the city told me there is no aftermarket eqvivalent and wanted to replacen the whole radiator + ATF where hoses are leading to the other assambly,.... Crazy. Price would usually skyrocket
reaching zilion... :-) GL.

Originally Posted by El Cid

WARNING!!!! Coolant is a dangerous poison. The odor is especially attractive to dogs and cats and it will KILL THEM.
It has to be disposed of properly and not down a drain or in backyard or in storm sewer catch basins. Any liquid that leaks onto the driveway, ground, etc. must be immediately removed and disposed of properly.
Better to let your dealer or an approved auto maintenance facility do this.

Originally Posted by Arrie

After 174000 miles changed the coolant on my 2010 E550. Was able to open the drain without breaking the plug that some others experienced . Sprayed WD-40 on the plug before opening it.

Used my Mity-Vac to pull the coolant out very quickly. Got 5 liters of it out, which is very small amount for a 5.5 liter engine. Manual says 5.2 liters so I think I got it out well. It all came out very clean with faint yellowish color. The new coolant I bought from the dealer is blue so I wonder what I had in my engine as the color is so different? The dealer parts said the one they sold me is the only one they use for all cars.

Anyway, the plug that others have has breaking when removing came out without much trouble in one piece but before I went to do this job, based on the other comments, I went to my local Dodge dealer to see if they have the plug shown in the picture of Vilem's post and they did, see the picture below. This plug is 100% match other than the flat "handle" to turn it is longer than the original part. Cost $15+tax. Far cheaper than buying and changing the whole radiator that MB says.

You can read the Chrysler part number on the plug: 4644269-4. I'm not sure the "-4" is part of it but anyway.

Originally Posted by 1guitar

Just finished changing the coolant in my 2010 E350 and it's about the easiest job you can do. The dealer gave me a quote of about $325, my total cost with some sweat equity of about 1 1/2 hours and $25 for the correct MB coolant that I bought from a MB parts seller for $25 for a gallon which is more than enough, oh, plus two gallons of distilled water, another $3. Here we go, firstly, remove the forward most plastic panel that sits underneath the engine between the front bumper and the engine oil pan, you can't screw it up as it's the first panel you can remove underneath the front of the car, the front of this panel sits forward and above the front bumper, the rear of this panel sits above the panel behind it, it takes a little elbow grease to fit it back in once you've removed it but what I did was place a small piece of blue painters tape next to every hole in the panel where the screws hold it onto the small clips on the chassis so you will remember where every screw and washer should be put back. Once you have removed the panel, get yourself a 6 gallon anti-freeze drain basin, I bought mine at Auto Zone for about $12. With the front bottom panel removed on the drivers side of the radiator you should see a petcock drain screw with a yellow line on it as well as another yellow line above and below it, looking at them they form a straight line. Even though MB directions for flushing the radiator says there should be a round red drain plug, it wasn't there. Mine was just a black drain plug with a yellow line on it. Once you have located the drain plug, turn the plug counter clock wise about 1/4 of a turn until the coolant starts to trickle out of it. Remember, remove the coolant cap that is located on the passengers side of the engine compartment from the coolant reservoir and make sure you have your 6 gallon coolant catch basin under the petcock drain plug that has a yellow line on it. Don't try to fully unscrew the drain plug, just a 90 degree turn will do it. My coolant took about 20 minutes to fully drain and held about 5 quarts to fully refill it. Although the system on my model holds about 8 quarts, as with most coolant systems, you won't be able to get every ounce of old coolant out, don't worry about it. Once your coolant is fully drained turn the drain plug back clockwise (from left to right) about 90 degrees. After that mix your coolant with distilled water at a 50/50% mix and start filling the coolant reservoir, use a funnel when refilling it as you don't want the coolant all over the engine compartment and garage floor. You can just pour in a full gallon before you have to start being mindful of how much more she will take. After you've got a gallon it start her up and turn the heater all the way to HI on Auto and let the engine warm up until the thermostat opens up, after that get in and take her for a short ride with the a/c on if you like as what you want to do is get her to operating temperature, than carefully open the coolant reservoir and finish filling with coolant. If your cap is too hot to remove just let her sit overnight and add enough coolant to bring the level to where you see two lines on the back part of the reservoir, that is where you want your coolant to be as you need to leave some space for the expansion of the coolant when the engine reaches operating temperature. Good luck to all!

Originally Posted by S-Prihadi

There is two way to evacuate air from the cooling system.
I tried vacuum and pressure.
Pressure is cheaper and better from DIY perspective.


Pressure ? Why and how pressure can help ?
Fill up coolant to maximum possible after any kind of work involving coolant partial drain.
Use radiator tester and pressurized to 15 psi and leave it at least 12 hours.
The thermostat is not a 100% blocked type even when not opened, it has small hole.
By pressurizing with air at the coolant recovery bottle, you are also pushing air out from where it is hiding by using coolant as "hydraulic" fluid.
You will add coolant by now.

Next day while keeping eye on the coolant level, turn engine ON and heater to maximum to allow the small electrical motor which circulate coolant to HVAC heater core to also work.
Make sure engine reach operating temperature and do blip throttle to 3,000 ish RPM once in a while, the top hose which is the thermostat housing to radiator should be hot, means coolant is flowing from
engine block to radiator ( thermostat fully open ).

Check coolant level when engine cool down.
Drive agressive next day and check coolant again, usually you need to add a tiny bit here, perhaps 5mm to 1cm coolant level.
By this time, your cooling system is almost zero air.
Control coolant level in the next few days, usually me do the check like 3 - 4 times until I am happy.
Anyway I check my coolant level so often without opening the cap, the white and black plastic color of our coolant recovery bottle is easy to see thru with or without torchlight assist.
My full mark is all white plastic gone.

NOTE : I am in the tropics, so getting my engine hot is easier.