Hey guys, how's it going? Hope all is well.
I did more work on the E420!
So according to my to-do list, I was supposed to do the coolant flush, but discovered some "oh noes" when removing the splash guard.
The lower radiator hose was leaking from two ends, the connection to the radiator and the water pump side.
Also noticed the bottom left side of the radiator was wet. Later discovered it was the nipple on top left of the radiator that was leaking and it was running down on that side.
So I ordered a new lower radiator hose and nipple with O-ring. Also got a new thermostat and the short L shaped hose. Figured might as well replace those while I'm in there.
Coolant mixed with distilled water, also got a hose for draining both blocks and radiator.
Broken radiator drain plug. I mean it looked all fine, but when I was inspecting the car I touched it and it fell apart. Had to use a soldering iron to melt a slot to fit a flat headed screw driver in and was able to unscrew it.
Anyways, I drained about 8.5 quarts from the radiator and both blocks combined.
New coolant vs. old coolant. Notice how the old coolant is orange!
Removing the old radiator nipple took some time! I used the method in the manual with a 9mm straight ring wrench and a flat head. I didn't want it to break and pieces fall into the radiator so I took my time on this part of the job. I later talked to my friend who is a MB technician and he said when the radiator nipple leaks we usually just replace the whole radiator!
New radiator nipple vs. old one. See how the O-ring is so flat on the old one (bottom), it looks like it's part of the nipple.
Replaced the thermostat and the short L shaped hose connection between thermostat and the water pump.
Replaced the lower radiator hose and started filling up the system from the top radiator connection, then the coolant reservoir. Started the car and went under the car to see if anything is leaking didn't find any leaks. Got the car to operating temperature, where the thermostat opens up. This allowed the coolant level to go down so I added more coolant Went under the car again and inspected everything. Didn't see anything leaking. Took the car for a short drive and came back home. Again inspected the system for leaks and didn't see anything.
Next morning I noticed there was coolant under the car!
Coolant was leaking from the same places like the old hose!
This is where I messed up. I should have read about this before ordering the parts. So I got the Rein/CRP hose from RM European. Old hose was also CRP.
I started searching the web to see whats the issue and noticed that this is a known issue with Rein/CRP brand! I've used this brand years before for my 190E and E46 with no problems, but I guess they are no longer reliable.
Called the dealership and bought genuine hose (3x the price of Rein).
Notice how the old hose has bigger opening than the MB one!
Anyways, drained the radiator again and replaced the hose and filled up the system. Been checking the car daily and thank god, it has not lost a single drop of coolant!
Now I have to figure out how to return this to RM European.