dustinN

Any one knows the location of radiator drain plug? Thanks.

coobah

Usually in the left bottom corner from behind.

equitiesguy

While you can drain the radiator from the petcock located on the driver's side, bottom corner of the radiator, you run the risk of stripping out the garbage plastic threads Valeo/Behr uses for it.

I usually drain mine from the intercooler pump connection. You can save it from there also if you aren't planning on flushing it.

coupesedan

I do it this way too. You can easily control the flow by screwing and unscrewing the cap.

dustinN

Thank you al. I found it. I tried to follow the "how to" section for E class but the color and shape they have mentioned are nothing like what I found, that why I had trouble to locate mine. The drainage plug on my vehicle is black and has a handle that you can open it by hand. Just turn counter clockwise 45 degree and pull it out. Yes, it's on driver side, on the bottom, on the side,

dustinN

equitiesguy

Right. They tend to break, then you have to replace the entire radiator. Anyway, good luck.

dustinN

Oh I see. Can you me the right way? Where is the location of the intercooler pump connection? What does it look like? Thanks.

coupesedan

Just realized you have an E63, so it's not applicable but you may have an Aux water pump in a similar location. Your other alternative would be to disconnect the lower radiator hose, but that comes with the risk of breaking the fitting.

dustinN

It's a bit too much work for me. Thank you anyways.

equitiesguy

When I drain my radiator from the low temperature circuit pump hose I can get nearly 3 gallons out. Car holds 3.5 gallons. Chances are if you flush it once, it's mostly all water at that point. It's also a convenient spot that it can be drained right into a collector, and won't get all over the belts like a radiator hose pull.

Just add back in two gallons of anti-freeze FIRST, then fill with water until it's full and you're more than fine. For 50/50 mix all you need is 1.75 bottles of Mercedes coolant. Remember to use distilled water for perfect pH.

coupesedan

Just use Zerex G48 50/50, $13 at walmart. It’s cheaper per gallon than MB concentrate. If you’re cheap you can save about $5 per 2 gallons by using BMW concentrate.

equitiesguy

You're not supposed to mix anti-freeze types, so that would require a complete purge. I just paid $20/gallon for the Mercedes concentrate, so paying $26 for two gallons is actually more expensive than my $1.00 of distilled water ($21.00).

coupesedan

Mercedes Blue Coolant = BMW Blue = Volvo Blue. They're all G48, just buy the cheapest

dustinN

It leaks badly not too long after I changed my coolant. I think I broke the valve you have mentioned. The tech said I need new radiator. I don't see any leak looking from the top or both side of the radiator. it could be that valve or some thing else from the bottom, didn't get a chance to craw underneath the car yet. Just wish it was a hose or something Lesson learned the hard way.

equitiesguy

I'm sorry to hear that. Should be verifiable by looking at the petcock, and seeing antifreeze. Should check if that has an o-ring that can be replaced you possibly damaged. It's one of the reasons I never screw around with it.

I would also look up high on that side with a UV light for a crack in the tank. That tends to be the side where an older radiator tank would make a 1/4" miniature crack, and run down to the bottom from there.

dustinN

Thank you.

Yuille36

If you fear damaging your radiator or petcock, then take it to a shop and let them purge and fill it. I do this every two years, they use a machine that extracts all the old coolant, then sucks new coolant into the system, thereby removing any air pockets in the entire system. Then we run the car for a few minutes and top off the coolant as needed. Bam.....
Cost <$140 no fears or tears 🤔

machild

If the radiator uses the very common drain 000 500 01 85 and it happens to break you do not have to replace the radiator. They are readily available from online MB dealers and on eBay at about $7 https://www.ebay.com/itm/Radiator-Dr...AAAOSwuxFYuJQS

Yuille36

Here’s a nice picture of the petcock, which is on the drivers side.

equitiesguy

It's not a machine. I have a Snap-on coolant filler that vacuums down the system with air, extracts the coolant, and then refills it. I use it on my 599GTB.

On the CLS55 (or E55) you can just bleed it through the actual bleeder line at the top of the engine (rubber plug, put a hose on it leading back to the reservoir and get out 99% of the air from both sides of the system (low temperature circuit and engine circuit) while the system is filling. As soon as you run the car, it will continuously bleed out the air until nothings left. Use a clear hose if you're new to this type of work, and you'll see solid fluid instead of air bubbles.

The vacuum system also doesn't pull out all of the coolant from both systems, which is why I never bothered with it on the Mercedes. The same way the oil suction won't pull a quart out of the front portion of the engine pan, so any lazy arsehole who tells you otherwise is leaving a quart of dirty oil in your car. Have to let it out from the drain plugs, which I would do anyway over "suction" from the top.

kevm14

I am having a dealer flush my brakes and considered adding a coolant change to the list. I did some poking around the forum and I see no need for the vacuum apparatus that is specified in WIS. Should be totally DIY-able. Plus, a forum member reported a heater valve O-ring failed when vacuum was applied to the system. No need for any of that...

Yuille36

I’ve never bought into the hype, of using suction to extract oil from the pan. I always preferred draining the pan, and oil cooler as this method leaves very little residual oil inside the engine.

dustinN

Update ... I had to replace the whole radiator. The tech estimated 2 hrs for the job but it actually took him 4.5 hrs to get it done. I'm glad I didn't try to do it myself :-)