'04 C320 Oil leak at Oil level sender 0-ring
#1
MBWorld Fanatic!
Thread Starter
'04 C320 Oil leak at Oil level sender 0-ring
Hi,
On my recently purchased '04 C320 4Matic, oil is heavily leaking from the Oil Level sender unit that is mounted on the oil pan on the passenger side. I think the o-ring on the sender unit is the culprit.
I bought new o-ring at MB dealer. I see that I'll have to drop the lower oil pan to replace this o-ring. There is no gasket for the lower oil pan; I think I'll have to use sealant.
O-ring is the part # 11 in the attached picture.
Oil pan is #35 in the other picture.
Question: what sealant is appropriate for this application?
If any one else replaced this sender unit or the o-ring, any tips?
On my recently purchased '04 C320 4Matic, oil is heavily leaking from the Oil Level sender unit that is mounted on the oil pan on the passenger side. I think the o-ring on the sender unit is the culprit.
I bought new o-ring at MB dealer. I see that I'll have to drop the lower oil pan to replace this o-ring. There is no gasket for the lower oil pan; I think I'll have to use sealant.
O-ring is the part # 11 in the attached picture.
Oil pan is #35 in the other picture.
Question: what sealant is appropriate for this application?
If any one else replaced this sender unit or the o-ring, any tips?
#2
Super Moderator
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If you can't get the Benz sealant then the Yamabond series from Yamaha is excellent for sealing aluminium casings with no gasket. Yamabond 6 = thick & expanding - Yamabond 5 = thin. etc.
On no account use crap like Formagasket.
The racing fraternity survives on Yamabond.
On no account use crap like Formagasket.
The racing fraternity survives on Yamabond.
Last edited by Glyn M Ruck; 10-05-2010 at 09:37 AM.
#3
Super Moderator
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Oh! & never seen this job done on a 4Matic but make sure that the sensor/sender is not cracked. Likely just the O ring.
#4
MBWorld Fanatic!
Thread Starter
Thanks Glyn for your feedback. I am not familiar with Yamabond. I will try in the order of MB sealant, Yamabond. Besides, I like the word "yama" the destructor.
Here are some pictures of the leak...
I have cleaned up the entire area and I have narrowed down the source of the leak as the oil level sender unit (hopefully, it's the o-ring).
Here are some pictures of the leak...
I have cleaned up the entire area and I have narrowed down the source of the leak as the oil level sender unit (hopefully, it's the o-ring).
#5
MBWorld Fanatic!
Thread Starter
Here is the update:
I bought the O-ring and the sealant at MB dealer and took the car to indy mechanic. Long story short, we couldn't get the lower pan separated from the block. We removed all the bolts that hold the pan (we made sure that ALL of the bolts are out); however, the pan stayed put as if the thing is welded. Couple of other mechanics tried as well... no luck. I didn't want to break the pan since I didn't have the replacement pan in hand. We put everything back... 3 mechanics shook their head. Looks like I will have to take it to the dealer and see if they have any tricks for removing the pan.
Anyone experienced something like this?
I bought the O-ring and the sealant at MB dealer and took the car to indy mechanic. Long story short, we couldn't get the lower pan separated from the block. We removed all the bolts that hold the pan (we made sure that ALL of the bolts are out); however, the pan stayed put as if the thing is welded. Couple of other mechanics tried as well... no luck. I didn't want to break the pan since I didn't have the replacement pan in hand. We put everything back... 3 mechanics shook their head. Looks like I will have to take it to the dealer and see if they have any tricks for removing the pan.
Anyone experienced something like this?
#6
MBWorld Fanatic!
Thread Starter
Finally, I ended up taking the car to MB dealer. They 've replaced the o-ring at a cost of $550 (charged for four and half hours of labor while the technician worked on the car for less than 3 hours). Glad that o-ring is replaced. That oil leak bothered me...
While I had the car at the dealership, I asked them to set Xenon=Present in the DAS. The technician tried for 15 minutes and came back and asked me if I had the instructions (which sub menus to go go to). He said that he forgot which sub-menus to go to. I looked up on this forum and showed him the instructions and he was able to set Xenon=Present. They charged me $57 for labor for changing that setting.
While I had the car at the dealership, I asked them to set Xenon=Present in the DAS. The technician tried for 15 minutes and came back and asked me if I had the instructions (which sub menus to go go to). He said that he forgot which sub-menus to go to. I looked up on this forum and showed him the instructions and he was able to set Xenon=Present. They charged me $57 for labor for changing that setting.
#7
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$600 - Ouch! You have to tell them what to do & they still charge. What a bloody cheek!
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#8
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Thread Starter
arggggg the saga continues. Oil leak at the o-ring (on the oil level sensor) is continuing even after paying nearly $600 for replacing the o-ring. I took the car back to the dealer and showed the oil leak. They are going to have to drop the pan again and see why it's still leaking. I made an appointment for Wednesday...
:-(
:-(
#10
MBWorld Fanatic!
Thread Starter
Glyn, I took the car back to the dealer for re-doing the work.
They claim that the oil is leaking from the Oil Level Sender Unit itself and not the 0-ring (because the o-ring is new). Since I didn't pay for diagnosis when I had the work done week ago, now I have to pay another $600 to re-do the work (drop the pan and replace the Sender Unit) PLUS I have to pay for the Oil Level Sender unit. As you can understand, I was not happy. I went to the manager and to the owner of the dealership and I explained the situation. Finally, we agreed that I pay for the price of the new part (Oil Level Sender unit) and one hour of labor. So, the total came out to $244. This is in addition to $550 I paid a week ago. Prior to taking the car to the dealer, I tried to replace the o-ring at an indy (they couldn't get the pan to separate because of the silicone sealant) and paid $100.
So, in the end, I paid $900 to replace the o-ring and the Oil Level Sender Unit. It is a lot of money just to take care of that oil leak.
I will watch the oil level sender unit area closely and see if the oil leak stopped.
They claim that the oil is leaking from the Oil Level Sender Unit itself and not the 0-ring (because the o-ring is new). Since I didn't pay for diagnosis when I had the work done week ago, now I have to pay another $600 to re-do the work (drop the pan and replace the Sender Unit) PLUS I have to pay for the Oil Level Sender unit. As you can understand, I was not happy. I went to the manager and to the owner of the dealership and I explained the situation. Finally, we agreed that I pay for the price of the new part (Oil Level Sender unit) and one hour of labor. So, the total came out to $244. This is in addition to $550 I paid a week ago. Prior to taking the car to the dealer, I tried to replace the o-ring at an indy (they couldn't get the pan to separate because of the silicone sealant) and paid $100.
So, in the end, I paid $900 to replace the o-ring and the Oil Level Sender Unit. It is a lot of money just to take care of that oil leak.
I will watch the oil level sender unit area closely and see if the oil leak stopped.