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Leaking Oil..What is this part called?

Old Nov 15, 2009 | 09:02 PM
  #1  
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2006 C350 Sport 6MT
Leaking Oil..What is this part called?

Hey guys,

I'm back with another problem

Yesterday I was heading onto the freeway onramp when I gunned my car and it felt sluggish. My friend asked me if I checked the oil level after the last visit to the dealer. So I checked the oil level today and approx I lost 1 quart.

I started to check for leaks, so far I have had 4 leaks.

Well I found a leak. Can someone be kind enough and tell me what the part is called and if it something serious?

Thank You,

Karo

P.S. The leak was a good amount. When I rubbed my finger below the area I got a good amount of oil. I can only imagine on the freeway

Last edited by W203E35; Apr 30, 2010 at 06:06 PM.
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Old Nov 15, 2009 | 11:22 PM
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THE C350
dam dude this sucks. wish i could help but i have no clue what that is. looks like you get another trip back to the dealer. wish my engine bay looked that clean
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Old Nov 16, 2009 | 02:14 AM
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Thanks Trey, yup I guss I have to take it in tomorrow. I already have had 3 leaks before.

Oil Breather was leaking
Rear Cam Plug was Leaking
Oil PCV Cover was Leaking

and now I have a leak from here.

No wonder I thought I was consuming oil. Soo many leaks (i'm not saying i'm 100% sure I am not consuming oil).
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Old Nov 16, 2009 | 02:19 AM
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Ahh found out what it is.

It's the "Rear Main Seal" (Number 33)



1) CYLINDER BLOCK
2) CYLINDER HEAD
3) HEAD GASKET
4) FRONT COVER
5) INTAKE VALVE
6) EXHAUST VALVE
7) VALVE SPRING SEATS
8) VALVE SEALS
9) VALVE SPRINGS
10) VALVE SPRING RETAINERS
11) VALVE KEEPER
12) ROCKER ARMS
13) VALVE LIFTERS
14) ROCKER SHAFT
15) CAMSHAFT
16) TIMING GEAR SET
17) ADJUSTER
18) VALVE
19) TIMING CHAIN
20) TENSIONER
21) CHAIN GUIDE
22) TIMING COVER
23) BALANCE SHAFT
24) WEIGHT
25) PISTON RINGS
26) PISTON
27) CONNECTING ROD
28) BEARINGS
29) FRONT CRANK SEAL
30) BEARINGS
31) THRUST WASHER
32) CRANKSHAFT
33) REAR MAIN SEAL
34) REAR MAIN SEAL RETAINER
35) PULLEY 36) OIL PAN
37) OIL PUMP
38) CHAIN
39) TENSIONER ARM
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Old Nov 16, 2009 | 02:44 AM
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C240
Hopefully it's the last leak you'll have!
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Old Nov 16, 2009 | 03:14 AM
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Originally Posted by laneshift
Hopefully it's the last leak you'll have!
Thanks , I really hope so too. I just checked my paperwork warranty ends on the 20th .

I think it's time to get Johnnie Walker Blue Label and go see my Service Advisor
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Old Nov 16, 2009 | 03:26 AM
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Rear main seal leaks are fairly common, I thought.
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Old Nov 16, 2009 | 03:55 AM
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Wow, how is your engine bay so clean?! The metal doesn't even look oxidized! Granted, my car is a year older, but still!
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Old Nov 16, 2009 | 01:48 PM
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My engine bay looks like that as well, and mine is an 05.
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Old Nov 16, 2009 | 02:03 PM
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That can't be the rear main seal. That can't be seen, because it is between the crankshaft output, and transmission input. You would see that leak commonly right at the split where the transmission and engine meet on the very bottom of the engine. What that is in your pics, I am not sure, let me do some digging.
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Old Nov 16, 2009 | 02:21 PM
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Ok, I looked on EPC net, and that is an expansion plug for a vacuum pump that is no longer applicable, so it is just that, a plug. In the notes it states: See DTB S-B-01.30/23a regarding oil seepage from back of cylinder head. Check you STAR service manual and see what it says.
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Old Nov 16, 2009 | 02:25 PM
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Originally Posted by Karo
I think it's time to get Johnnie Walker Blue Label and go see my Service Advisor
Did someone say Blue Label!!!!!!!!!! I am suddenly VERY thirsty
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Old Nov 16, 2009 | 03:24 PM
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Originally Posted by acr2001
Wow, how is your engine bay so clean?! The metal doesn't even look oxidized! Granted, my car is a year older, but still!
Originally Posted by LILBENZ230
My engine bay looks like that as well, and mine is an 05.
Maybe it's the weather? SoCal is pretty dry maybe this is the reason it doesn't look oxidized?


Originally Posted by johnand
Ok, I looked on EPC net, and that is an expansion plug for a vacuum pump that is no longer applicable, so it is just that, a plug. In the notes it states: See DTB S-B-01.30/23a regarding oil seepage from back of cylinder head. Check you STAR service manual and see what it says.
Thanks, I'm going to try to reinstall EPC and WIS (upgraded to windows 7 hope it works)


Originally Posted by johnand
Did someone say Blue Label!!!!!!!!!! I am suddenly VERY thirsty
Whenever you come down to SoCal I got some Blue Label for you
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Old Nov 16, 2009 | 03:53 PM
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Originally Posted by Karo
Thanks, I'm going to try to reinstall EPC and WIS (upgraded to windows 7 hope it works)

Whenever you come down to SoCal I got some Blue Label for you
It works in Windows 7, I am running it at home. on the Blue Label offer.
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Old Nov 16, 2009 | 07:39 PM
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Yup, You're right it does work.

Blue Label -FTW
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Old Nov 16, 2009 | 11:31 PM
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Originally Posted by Karo
Maybe it's the weather? SoCal is pretty dry maybe this is the reason it doesn't look oxidized?


^me

That explains it! The salt here is pretty harsh.
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Old Nov 17, 2009 | 05:40 PM
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Good news. Nothing major, I took it to the dealer and they said it was the cam plugs. The cam plugs had previously been leaking and I guess the dealer didn't fix it well the first time.
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