What is this leak now?
03-05-2022, 10:31 AM
#1
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What is this leak now?
2015 GL63 is due for 50k service and found this while doing brakes. Any ideas?
03-05-2022, 09:32 PM
#2
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2014 GL450, 1992 W140 300SD, 1993 W140 300SE, 1987 E30 Convertible
If it is bluish greenish it is leak from cooling system vent pipe. Since your car 2015 plastic is fragile and it will crumble if you try to pull it apart. Go by dealership, ask them for both parts number and buy it online - much cheaper.
03-07-2022, 08:43 PM
#3
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(Daily) 07 E320 Bluetec, 08 & 13 C300 4Matic, 83 300D Turbo, 14 E350 4M
It could be one of several things.. fine hydraulic fluid leak from the suspension/active sway bar system, oil from another component being slung by the belt or oil seeping it's way out of the charge air system.
I would choose to ignore it until it becomes a noticeable problem.
As mentioned already, regardless of how you handle it, you almost certainly will have to replace the entirety of the plastic coolant lines that run in front of the engine and to the turbochargers, as theycan, will break as soon as they are disturbed in any way.
I would choose to ignore it until it becomes a noticeable problem.
As mentioned already, regardless of how you handle it, you almost certainly will have to replace the entirety of the plastic coolant lines that run in front of the engine and to the turbochargers, as they
03-08-2022, 09:15 AM
#4
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I just ordered that part, google shop it for pricing, there are a couple dealers that sell it for $90. 166-500-10-91 Looks like the overflow line to me?
I need some CPS's as well, so it made sense to order and overnight. I have a disdain for my local dealer.
I would clean everything up real well, brake cleaner maybe and keep an eye on it every day or so until you find the leak. I would not ignore it, I have the worst luck of fatal failures at inopportune times.
I need some CPS's as well, so it made sense to order and overnight. I have a disdain for my local dealer.
I would clean everything up real well, brake cleaner maybe and keep an eye on it every day or so until you find the leak. I would not ignore it, I have the worst luck of fatal failures at inopportune times.
03-08-2022, 10:36 AM
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2014 GL450, 1992 W140 300SD, 1993 W140 300SE, 1987 E30 Convertible
It is actually 3 parts 166-500-10-91, 278-203-12-17, and 009-997-29-72. I tried to replace one, ended up replacing all 3 because of plastic crumbling. Same decease as Porsches and Audi...
Anyway brake clean it and see if it is leaking again before replacing, because for me it look like oil spray from belt which means could be oil leaking on belt somewhere else. Do not look like coolant.
Anyway brake clean it and see if it is leaking again before replacing, because for me it look like oil spray from belt which means could be oil leaking on belt somewhere else. Do not look like coolant.
Last edited by arsupisemnet; 03-08-2022 at 10:38 AM.
04-11-2022, 11:30 AM
#6
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Thread Starter
The dealership found the roll control hydraulic pump to be leaking and it is being replaced under warranty. It is a roughly $3k repair. Part is 000-329-02-00-80.
05-25-2023, 01:47 PM
#7
I found this thread via a google search, searching for that part number. I'm seeing a similar leak on our 2017 GLS 550 and I also think it's this pump. Looks like it's a $1000 part plus a good amount of labor. I was hoping it was just a pulley bearing that had gone bad.
