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If it was spraying coolant from the water pump, why is only that inclined part in front stained? (first pic)
I think it leaks after the engine is stopped and cools off, then that pipe in pic 5 contorts and sprays the still hot coolant. Maybe the coolant crust has "sealed" the crack somewhat now.
You're right ... nothing above that bar has stain on it, so the water was dripping down, not spraying up.
Okay, I think I'm just going to do a round of cleanup on the cooling system. The car is ten years old and has 120k miles. About time to proactively replace all those items that are failure prone at this age. According to Murphy's law, if I don't replace the water pump or radiator hoses or fittings now, they'll fail next month.
I'll put together a list of parts and post it for review.
Jkowtko, the 68-45 part isn't in that diagram - it's in another diagram that shows the radiator itself as well as the connecting hose, as part #65 iirc (not to be confused with the #65 in the diagram Glyn posted, which shows the hose socket itself).
I think I've got it here ...
... but I show a different part number for #65 than the one you mentioned.
==========
PARTS LIST
==========
Copying from EPC-net these are the following parts I would plan to purchase from the above diagram:
#65 ... A 003 997 17 89 ... Sealing Ring (qty 2)
#60 ... A 203 501 57 82 ... Hose, on radiator, top
#102 ... A 003 997 06 89 ... Plug socket, breather line
Since the top radiator hose is the hot one, I believe it is most prone to bursting (as it did on our Honda), so I would replace this one at a minimum, along with the thermostat fitting.
Below is what looks like a newer of Glyn's diagram from EPC-net ... they are slightly different though:
From the above diagram the parts on my purchase list are:
#5 ... A 271 200 10 01 ... Water pump
#17 ... A 271 203 02 80 .... Gasket, water pump to timing case
#56 ... A 271 203 05 75 ... thermostat (I believe doesn't include 68 or 74)
#65 ... A 271 200 12 56 ... Fitting, cooling water outlet
#68 ... A 029 997 21 48 ... seal ring (fitting)
#74 ... A 271 997 00 45 ... seal ring, cooling water outlet
#106 ... A 001 997 55 41 ... seal ring
#122 ... A 013 997 98 45 ... O-ring
#130 ... A 271 200 15 52 ... Heater feed, at cylinder head (includes #140, #146, and #149)
#140 ... A 027 997 90 48 ... Seal ring
#149 ... A 022 997 98 48 .. seal ring (for temp sensor)
The temperature sensor was replaced twice already so I don't plan to replace it right now other than a new seal since I have to remove it from the pipe. The thermostat was also replaced a few years back along with the temp sensor, but I would replace that again just to reset the clock on that entire segment of the cooling system.
Are there any changes to the above list that you would recommend?
I also have two part number discrepancies to note -- on parts.com I found the following:
A 271 200 02 01 ... water pump which appears to include the gasket
A 271 203 06 02 ... heater feed pipe at cylinder head
Are these part part numbers just old? Or are they packages which include seals/gaskets?
Okay, I just purchased Heater feed pipe #130 at the local dealership ... $59 + tax. It includes the O-ring #140, temp sensor #146 and O-ring #149.
I also picked up the Breather line plug socket #102 on the first diagram ... $10.50 + tax.
Other parts were on backorder so I stopped here.
They had the water pump in stock ... for $249! So I also passed on that. Parts.com has one listed for $123 with a different part number, and shows that it includes the gasket. Since The water pump isn't leaking right now I think I'll have some time to verify that the one from parts.com is just an old stock number, and hopefully still genuine MB.
The new pipe is on, so if anyone needs a perfectly good #130 pipe that just needs an o-ring, let me know.
Fyi I snapped the head off the radiator drain plug when I was tightening it, so my project is on hold in the driveway until the dealership gets in this minor part (they didn't have it in stock). Argh!
$80-100 and I can't find it anywhere cheaper. Other than the pipe socket #102 which costs $10, it's just two rather small pieces of 5/16" ID pressure coolant hose and a bent piece of 5/16" metal tubing. Makes no sense why it's priced so high.
Fyi the hose is stamped with the part number for the entire tube assembly ... so it looks like they have no intention of selling the pieces separately:
That being said, I would like to replace the two pieces of rubber tubing on this since they are showing signings of hardening with age. Short of just heading to the auto store and buying bulk hose, does anyone know where I can get this those from?
Fyi I finished the coolant flush today. drained the radiator only and refilled with distilled water 5 times. Each time I drained 1 1/4 gallons of water, so 3/4 gallon is hiding in the system. Per the photo the last drain was pretty much clear, so no need to pull the plug on the engine block for this effort.
My final fill was straight blue coolant, one gallon, and top off with water. That ends up with a 50/50 mixture.
Wow, that's pretty dark...
Hmm, looks like per manual, there is less than 2 gallons in the system.
However, my coolant strength meter was showing weak strength after I filled the mix according to the manual. So full gallon of MB coolant in then top off with water seems the right thing to do.
I mentioned that on post #23. Oh well, can't do any wrong by replacing that pipe.
I would eventually like to replace all of the plastic and rubber in the cooling system ... because eventually those parts are going to break. I don't mind having spent the $60 instead of maybe 5 ... saved a lot more than that on labor ... enough to buy the water pump, thermostat, housing, upper radiator hose and all seals and o-rings.
Fyi I am getting ready to toss the old parts, which includes a good header pipe, temp sensor, and overflow hose nipple adapter. If anyone wants them I have them posted in the Classifieds --
Did my pipe #130 today. The o-ring was squared even worse than on jkowtko's picture...
What made me laugh though, is that the front bolt was loose! Maybe from all the coolant lubricating it and the vibration helping it unscrew?
I found it easier to undo the three bolts on the metal exhaust shield and remove it out of the way, then the two bolts on the pipe are a piece'a'cake.
Lubed the o-rings with a dab of silicone grease and they went in effortlessly.
A fairly definitive, cheap, and easy way to find the leak is with a pressure tester. Although I haven't used my pressure tester on my c230 yet, it looks like there is an adapter that fits on the expansion tank. Just make sure the car is completely cool, pump it up, and see if it holds pressure and it coolant shoots out. You can google the procedure, or just ask someone at Advance Auto. No more mystery coolant leaks!!
Would it be possible to find the dimensions of these O-rings somewhere? Like if any of you happen to have a #140 in hand, what is the outer diameter and thickness?
Because I can get literally any type in the world from a local company that has hundreds upon hundreds of standard rings on the shelves.
If they don't have it in store, they can make one of almost any size by welding together the ends of raw string material. NBR, Viton, you name it.
Which is vastly preferable to ordering a single darn ring from some importer and waiting a week to get it, paying $20 just for the shipping of a 50-cent thing.
... but I show a different part number for #65 than the one you mentioned.
==========
PARTS LIST
==========
Copying from EPC-net these are the following parts I would plan to purchase from the above diagram:
#65 ... A 003 997 17 89 ... Sealing Ring (qty 2)
#60 ... A 203 501 57 82 ... Hose, on radiator, top
#102 ... A 003 997 06 89 ... Plug socket, breather line
Since the top radiator hose is the hot one, I believe it is most prone to bursting (as it did on our Honda), so I would replace this one at a minimum, along with the thermostat fitting.
Below is what looks like a newer of Glyn's diagram from EPC-net ... they are slightly different though:
From the above diagram the parts on my purchase list are:
#5 ... A 271 200 10 01 ... Water pump
#17 ... A 271 203 02 80 .... Gasket, water pump to timing case
#56 ... A 271 203 05 75 ... thermostat (I believe doesn't include 68 or 74)
#65 ... A 271 200 12 56 ... Fitting, cooling water outlet
#68 ... A 029 997 21 48 ... seal ring (fitting)
#74 ... A 271 997 00 45 ... seal ring, cooling water outlet
#106 ... A 001 997 55 41 ... seal ring
#122 ... A 013 997 98 45 ... O-ring
#130 ... A 271 200 15 52 ... Heater feed, at cylinder head (includes #140, #146, and #149)
#140 ... A 027 997 90 48 ... Seal ring
#149 ... A 022 997 98 48 .. seal ring (for temp sensor)
The temperature sensor was replaced twice already so I don't plan to replace it right now other than a new seal since I have to remove it from the pipe. The thermostat was also replaced a few years back along with the temp sensor, but I would replace that again just to reset the clock on that entire segment of the cooling system.
Are there any changes to the above list that you would recommend?
I also have two part number discrepancies to note -- on parts.com I found the following:
A 271 200 02 01 ... water pump which appears to include the gasket
A 271 203 06 02 ... heater feed pipe at cylinder head
Are these part part numbers just old? Or are they packages which include seals/gaskets?
Thanks. John
Do the 2 bolts for the heater feed pipe have a specific torque value? Mainly the one located at the front of the engine where the coolant goes into the head??? Mine is leaking from front where the bolt is maybe bad o-ring and I think it also has a hairline crack where it bleeds out.
I just tightened mine snug ... which equates to 7-10 ft-lbs.
I also just looked up a spec sheet for torque spec on water pump bolts.
M6 - 10 Nm
M8 - 25 Nm
Since these bolts aren't holding together two pieces of material to prevent a leak (i.e. they have separate gaskets that aren't torque sensitive) I think you just want them snug enough that they don't loosen up over time and fall out.
WTH guys... Looks like my water feed pipe #130 is leaking again where it mates with the head.
What have I done wrong? Not enough torque on the bolt? Pretty sure I lubed the o-ring before installation...
How long has it been? I am only 2 years into mine. Is the O-ring a genuine MB part?
Since it's an o-ring the bolt only has to keep the pipe from coming out of the socket in the head ... torque shouldn't matter as long as the bolt doesn't fall out.
I lube rubber gasket parts with silicone grease now ... if you don't have any you should be able to get it in the kitchen faucet section at the hardware store. it looks like vaseline and costs around $3 for a small container.
I never bothered lubing any of the O-rings and never had any leaks since replacing all the plastic pipes. One thing I'm always afraid of is that the lube might liqueify under high temperature and cake somewhere into the system. Does MB recommend any lube here?
Sounds like bad luck. Hopefully replacing the O-ring solves the problem.
Yeah, I bought an OEM pipe together with o-ring from the dealer.
Replaced a little over a year ago.
I believe I also used some kind of teflon lube called "Aladdin magic lube"
The pipe does not feel loose, so the bolts are ok still.
Hmm, wait. If the coolant is leaking out, it should be leaving these whitish stains? Mine just looks like "wetness".
Maybe that's the excess silicone that liquefied and now sits there...
Hmm, wait. If the coolant is leaking out, it should be leaving these whitish stains? Mine just looks like "wetness".
Maybe that's the excess silicone that liquefied and now sits there...
I can believe this. If you don't have that whitish stain everywhere, and your coolant level isn't dropping, then maybe no problem ...
Hey Guys I finished replacing my water feeder pipe last weekend and everything seems to be holding up great. Took me about 2 hours but struggled with the dam hose clamps and my thermostat housing also cracked when I pulled it out.(Didn't expect that one . I'll post some pictures later on but my pipe was cracked at the header connection so I assume when the system depressurized coolant was seeping out since the there was no more tension with the o-ring.
VVF- the pipe you for from the dealer was that the newer part number version? I would recommend you buy your parts from a website I found called fcperuo.com They have a lifetime guarantee on all their parts for the life of the car. So if like for example the pipe fails or the o-ring they send you a replacement free of charge. They are comparable to autohuaz but with a way better parts guarantee.
Any instructions or videos on removing and replacing this part? I only see the instructions for a different pipe, but may have missed them.
I'd appreciate a quick response as time is of the essence on this- my car had lots of work done and days after picking it up a leak from this pipe left a big puddle on my driveway. Seems like too much coincidence. Any possibility that they may have damaged this pipe, collateral damage when making other repairs? Here's the list of parts replaced:
Engine vent hoses
Camshaft Adjustment Solenoid(s) and Adapter Harness(es)
Intake Manifold R&R
Crankshaft position sensors - Ignition Syst
O2 Sensor- Front of Catalytic Converter
O2 Sensor- After Catalytic Converter
Wiring harness - for engine
Position Sensor
Electrical Wiring Harness
Starter Line
Flange Gasket
TS Electrical Wiring Harn
Exchange Control Unit
2 different Sender Units
04-02-2015, 12:43 AM
(first pic)
. I'll post some pictures later on but my pipe was cracked at the header connection so I assume when the system depressurized coolant was seeping out since the there was no more tension with the o-ring. 
