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I used that one. Make sure to dig around in the hole in the head make sure you get all the of oring and plastic out, mine cracked off and crumbled on the inside.
Slammer, good find. Just curious for my own research, was your car still using MB coolant or off the shelf from the local parts store?
I use only MB factory coolant from the dealer. There's that new blue stuff (Zerex G-48) that supersedes the old beige stuff (Zerex G-05). Both can be used concurrently (ie no need to drain the beige stuff before adding the blue stuff). The stuff in my engine is currently a mixture of both. I used up all my spare jug of beige stuff, then started topping up with the blue stuff as necessary.
Factory is the way to go. Other than the colour (new blue stuff), the coolant looks as good as the day I bought the car. There are 3rd party coolants available that also meet the MB 325.0 specification, but I didn't bother as the price difference is only $10 or so.
Last edited by slammer111; Dec 21, 2022 at 12:06 AM.
HEY IM NEW TO THIS FORUM BUT IM HAVING THE SAME ISSUE ON MY 2005 C230 Kompressor Sedan Sport package. It leaks rarely mostly if i punch the gas an take it over 100 mph. There has also been times i just turn it on an move it eight feet an shut it off an when i wake up in the morning find a leak or spot of coolant I also have looked behind the engine an see the coolant leak just dnt know where exactly its coming from. Also the temp nvr rises over 80 so i know its not causing the car to over heat do i giys think i might have the same problem if so how much would a shop charge me to do the job
My engine seems to be leaking coolant only when cold. I'm looking in the back underneath the vacuum pump and noticing what looks like dried coolant on the tranny case, directly underneath this pump.
When the car is running, nothing seems to leak. However, there's a puddle on the floor when I back my car out in the morning.
Physically below the pump is a coolant hose, which was covered dried/sticky engine oil from when my pump was leaking (which has been repaired since). No coolant - none I could see or feel at least. I wiped down the hose and squeezed the length of it, but couldn't find anything. There are also some dried coolant streaks on the exhaust pipe, up to the cat but not above. Not sure if that's just dried spillage from topping up the expansion tank though. I wiped it down and will look again in a few days.
The front end of the engine seems perfectly dry upon visual inspection. Absolutely no dried coolant.
Any ideas where I should start looking, before I throw more parts at the car? And MB is supposed to be over-engineered..
In this diagram, the hose that goes closest to the leak isn't shown. It's right where the number 124 is (ie connects to the "lower branch" of 130). Anyone have the diagram that would show that hose?
You need to use a pressure tester to locate the leak!!
A pressure tester could be used to find the leak, but this one is pretty obvious because of the wet spot. So far all 3 leaks I've had with the coolant system have been because of cracked plastic pipes - a different one failed for each leak. See above for the PNs for all 4 pipes I replaced. (I replaced the 4th one preemptively)
Also I know I caught all the leaks because the coolant loss has completely stopped.
Last edited by slammer111; Dec 21, 2022 at 12:07 AM.
So thank you for finishing this thread... I was also losing water for quite some time but only when you put foot in the hook.
Randomly decided to Google it one more time... and vola... found this thread and decided to push my phone into the back of the engine.
I'm betting this thread saved me from some serious damage, mine was about to explode.
One question: Would this be normal color for the water to come out? Obviously it's high pressure so it would go all over the place? (the car has 220k kilo's on, so I just need to keep an eye on the headgaskets)
I'm not sure about the colour there. It almost looks like engine oil?
Easiest way to tell - does the fluid turn white when dried? If so, it's coolant. If it's still brown, it's engine oil.
The M271 also leaks engine oil at the back of the engine when the seals fail at the booster pump. This is another common problem. See this thread for additional details. Good luck.
I'm not sure about the colour there. It almost looks like engine oil?
Easiest way to tell - does the fluid turn white when dried? If so, it's coolant. If it's still brown, it's engine oil.
The M271 also leaks engine oil at the back of the engine when the seals fail at the booster pump. This is another common problem. See this thread for additional details. Good luck.
Thanks for the reply sir.
I'm thinking it might be a mixture - The car doesn't misfire or lose oil. (other than your normal amount) It does turn white if you look at the pipe above it - but I agree it looks a bit like coffee (oil water mix)
I checked it now again and it would seem I might have to replace that too. See they are a bit pricey... better than a head gasket though!
Thanks, this was super helpful! May all your mercs hit the 1mil KM mark.
what did anyone who has fixed this pipe remove to get to it? These hoses are in my way and not sure how to remove them without breaking them, any suggestions?
A pair of pliers or a crescent wrench (ie something with a smooth contact surface) works. Squeeze above the ring part, then twist and wiggle the valve upwards. It takes a little bit of wobbling to get it off.
Afterwards, as the rigid plastic pipes can "spin" inside the joints, just rotate the other end of the pipes upwards and out of the way.
Last edited by slammer111; Jul 16, 2020 at 01:01 AM.
Thanks for the help, I got the hoses off and replaced the pipe. Had to pry the broken piece out like everyone else. Used the smallest wrench I had to stick in the hole and pull it out. Fun stuff. Now for the oil leaking cam solenoid and the breather hoses 😜
Here's a pic of the plastic piece that gets stuck in the engine if anyone is interested. Easiest way to get it out is use something to put in the hole and hook the back of the plastic and pull it out.
So I finally got around to replacing the next coolant pipe. This is the physically big one (271-200-15-52) above the exhaust manifold. Looks like MB has superseded this one - the original part was 271-200-11-52.
Tools required:
Coolant extraction device (if you don't want to kill fish)
External Torx E10 bit
Various extensions - I used a 2", 3", 6", and 10" for this job; a flex extension would honestly be best in this case
Hose clamp tool (pliers *may* work if you're lucky)
Coolant for topping up (if required)
Pry tool (slot screwdrive also works) for removing hoses from pipe
Instructions
1. Open and drain the coolant expansion tank. I only drained about 75% of it, but it was sufficient. As long as the level drops below the lowest point of the pipe (the connection with the O-ring), you're good.
2. Disconnect pipe socket (the flimsy one that seems to be exploding on everyone). Pry up the wire connector with a screwdriver, and unplug.
3. Disconnect the 2 connectors. One is the coolant temperature sensor; the other is some 3 wire connector and harness, not sure what it does. The latter broke on me (plastic is way too this on this piece) when I was trying to unhook the tab. The part for that thin piece is A203-545-30-28, and the other half of the connector is 000-545-25-84.
4. Remove heat shield above exhaust manifold. 3 external Torx bolts. Note that one is slightly longer than the others - this one goes towards the front of the car. To get this thing out, I had to flex (almost to the point of bending it) the part to wiggle it out. There is 1 cable (goes around the power steering reservoir) that may get in your way, but on my car it was zip-tied. I simply fed more cable upwards to get the required slack. The cable can be fed back down through the zip ties after the job is complete.
5. Loosen 2 hose connections towards rear of car. Pliers may work depending if the tabs are at a good angle, but this I would imagine is luck of the draw. My hose clamp pliers took these off in seconds. Pry off the hoses, being sure not to damage them.
6. Remove bolts for pipe (2 total). A 2" or a 6" extension will work, but nothing in between because of another part in the way. A flex extension would probably work best here.
7. Remove pipe. The O-ring connection is tight - wobble the pipe back and forth and eventually it'll pop out.
Reverse everything when done and you're good to go.
Looks like the 15-52 piece is made of a different kind of fibre-reinforced plastic. The plastic is black instead of dark brown, but the fibers have a much more shiny appearance. The old pipe is the top one in the photo.
Hey guys I'm new to this forum and I have the same problem. That feeder line had a crack at the bend towards the front of the engine and I think also from the bolt its seeping out. When you reinstalled the pipe what torque vales did you use if any for the two bolts that support the feed line. More importantly the one that mates with the cylinder head at the front of the engine? I just ordered the new feed line and also has the new part # vs the original in my car. Does that new feed line come with a new temp sensor or do I still need to get a new one?
I didn't use a torque wrench at all. I just made sure the bolts were snug.
The bolts for the coolant pipes really just hold them in place. They're not load-bearing.
My new feeder pipe came with a temperature sensor already attached and clipped in. If it doesn't, just reuse the old one. Might need a new O-ring though.
Last edited by slammer111; Nov 26, 2020 at 07:42 AM.
Febi is a reputable aftermarket vendor so you'll probably be safe. I've seen aftermarket o-rings go bad though, so for those personally I'd stick to the dealer.
To be honest, it's just a pipe. Its only jobs are to not leak, and hold the associated hose in place. Not too much that can go wrong to be honest. If you need one, give it a go and let the rest of us know if there are any problems.
Last edited by slammer111; Dec 21, 2022 at 12:10 AM.
Wow, very timely for me this post floated to the top of the forum. Thanks a bunch for this thread Slammer! It appears I have this same leak. Where are you guys getting your parts from these days? An OEM source or website that has the parts diagrams would help me a bunch - I'm not sure if the parts are the same for my sedan vs the coupes.
Also, is anyone else having problems viewing the pictures posted? I click on them and a window pops up but just stays blank. I'm on a pc with Windows 10 and have tried on both the Edge browser as well as the old Internet Explorer.
Besides the dealer, there are many choices (you guys are lucky in USA). RMEuropean, FCPEuro, and AutohausAZ come to mind. AFAIK, the sedan and coupes have the exact same engines and powertrains. Nothing to worry about there.
The pictures on this site haven't shown up properly for years on my computer. If you figure this one out please let me know.
Last edited by slammer111; Nov 26, 2020 at 07:42 AM.
I am new to this forum and I have the same identical coolant leak. Actually I originally posted about the leak in the benzworld forum and one member ( very nice of him ) inserted a link to this thread.
I am willing to give the aftermarket part a try, can't remember the name. I think it is something like Febi?. Where can I buy this part, aftermarket?.
The other question I have is, I am not sure what I need to move out of the way to get to the part in the back of the engine.
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