GL Class (X166) 2013-2015 after facelift became GLS (X166)

GL450 coolant hose leak update, problem identified!

Old Feb 15, 2020 | 11:36 AM
  #26  
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2007 S550, 2013 GL450
A little bit of spit on the male connectors and a lot of elbow strength with a twisting motion while pushing it in. The bottom one went in pretty easily, but the top one gave me a hell of a time.
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Old Mar 31, 2020 | 12:10 PM
  #27  
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what size socket do you need to remove the bolt for the coolant hose?

also, how do you get the poly-v belt off?


thanks!

Last edited by bcgrant; Mar 31, 2020 at 04:52 PM.
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Old Mar 31, 2020 | 12:41 PM
  #28  
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found the drain plug. driver side on the inner edge. black plastic knob. easier to see looking down through the engine bay.
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Old Mar 31, 2020 | 06:50 PM
  #29  
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Is the bolt circled in yellow required to be removed or do the two hoses come out together? I cant get in to get this bolt out.

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Old Mar 31, 2020 | 11:18 PM
  #30  
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i had to take that bolt off, but it comes out pretty easily if you just come at it from the bottom side underneath the vehicle. The top nut stays put well enough to get it off.
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Old Mar 31, 2020 | 11:20 PM
  #31  
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i sent a reply to this message, let me know if you didn't get it @bcgrant . not sure why it didn't show up here.
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Old Apr 1, 2020 | 12:15 AM
  #32  
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One more question. The third coolant tube came with the clamp in the picture. How did you tighten it?





Last edited by bcgrant; Apr 1, 2020 at 05:36 PM.
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Old Apr 1, 2020 | 12:17 AM
  #33  
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Originally Posted by rickyanalog
i had to take that bolt off, but it comes out pretty easily if you just come at it from the bottom side underneath the vehicle. The top nut stays put well enough to get it off.

thanks man. That was super easy from underneath.
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Old Apr 1, 2020 | 05:35 PM
  #34  
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Old Apr 1, 2020 | 09:00 PM
  #35  
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Thanks. Was thinking that bolt was holding on the pulley and that there should be a separate bolt. Thanks for your thread. Helped me a lot.

Got the replacement done today. Did take about 5 hrs plus a a second trip back to the dealership for an additional hose I broke and a trip to Home Depot.


1. Be very careful removing the third hose that attaches to the passenger side turbo coolant hose. I was super gentle and the plastic fitting still broke. Luckily the passenger side turbo coolant hose is very accessible and easily to replace. Nothing like the driver side. But it did require buying the fourth hose at +$80.

2. The one hose that attached to the center of the engine (I believe) has a plastic fitting that goes into the metal. When trying to remove it the plastic fitting broke off and was stuck inside. Tried to pry it out with every pick tool possible but no luck. Finally got it out by screwing a screw from home depot the same size as the plastic. Screwed it in and then pulled out the screw and plastic fitting. This required a trip to Home Depot.


Every coolant hose I touched (all 4) broke at the plastic sections. There was also visible deterioration on the inside of the plastic. It’s pretty sad they used such a crap plastic. My gl550 only has 38k which is pretty bad for these all to be cracking. Parts guy was not surprised as all and they were fully stocked with these parts.

$350 in parts and 5+hrs and my leak is fixed. All parts are replaced with the same cheap plastic that will likely fail again at some point. At least it’s good for now.

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Old Apr 2, 2020 | 01:02 AM
  #36  
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Originally Posted by mtm
Great, glad you got it sorted. So how did you finally get to the fitting on the side of the turbo? Any tricks to it?

I went from the front with a 12inch 3/8 ratchet to get the bolt off. It was pretty easy except being extremely hard to see. 8M. Getting the 2 hose fitting’s out was a Pain. Use a pry bar to put outward pressure while rotating the hoses up and down. It eventually comes out. Top line first and then bottom line. Top line is way easier. Bottom line took me some time. Be careful what your pry bar is pushing off.
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Old Apr 3, 2020 | 08:28 AM
  #37  
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job well done. mine took much longer and I almost gave up at certain points. It's a good thing I'm stubborn. But happy you got yours done.
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Old Jul 8, 2020 | 10:07 PM
  #38  
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Thanks to all the advice and pics, I was able to get the bolt off those 2 turbo coolant lines. It wasn't so bad but now I'm having a hard time pulling them out. Any ideas or tips on how you guys pull them out without damaging anything else?
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Old Jul 9, 2020 | 06:50 PM
  #39  
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Originally Posted by diamondblak05
Thanks to all the advice and pics, I was able to get the bolt off those 2 turbo coolant lines. It wasn't so bad but now I'm having a hard time pulling them out. Any ideas or tips on how you guys pull them out without damaging anything else?
had to use a long flathead screwdriver and pry it in there to wiggle them out. It was not fun, but they finally came out.
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Old Jul 10, 2020 | 04:28 PM
  #40  
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Originally Posted by rickyanalog
had to use a long flathead screwdriver and pry it in there to wiggle them out. It was not fun, but they finally came out.
I'm trying with a pry bar and a flat screw driver. Basically destroying the pipe but still can't get it out. This is really frustrating.
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Old Jul 10, 2020 | 05:40 PM
  #41  
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The upper coolant return line on the driver's side that breaks at the plastic component is the easiest fix. I learned this the hard way. Take the new hose assemble and remove the clamp to detach the plastic piece and using a new hose clamp of your chosing, attach the new palstic part to you old line still in the vehicle. This is how the dealer techs do these in less than 30 minutes. No serious disassembly required. refill and check the coolant level with the proper stuff and be done with it.
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Old Jul 16, 2020 | 03:00 PM
  #42  
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Originally Posted by rwhyde
The upper coolant return line on the driver's side that breaks at the plastic component is the easiest fix. I learned this the hard way. Take the new hose assemble and remove the clamp to detach the plastic piece and using a new hose clamp of your chosing, attach the new palstic part to you old line still in the vehicle. This is how the dealer techs do these in less than 30 minutes. No serious disassembly required. refill and check the coolant level with the proper stuff and be done with it.
Are you talking about the the driver side line with the large plastic housing? Or are you talking about the driver side line that the plastic housing mounts to the center of the block
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Old Jul 20, 2020 | 03:57 PM
  #43  
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Just did the 2 driver side lines. Was really easy getting to the bolt at the turbo from the front of the engine with a small 1/4 inch ratchet and i believe a 7mm socket. The hardest part was prying them out of the turbo. Oh and the part numbers vs parts diagram is different. The lower line apparently was revised but not revised when i got the part from the dealer. Overall job took about 2.5hrs. The pass side look very easy as everything is exposed.
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Old Aug 4, 2020 | 04:54 PM
  #44  
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Mine just sprung a leak at the plastic part that's bolted on the engine on the driver side. Parked the car OK, and then it just started spraying coolant on the exhaust pipe and splattering it everywhere.

I was hoping it would be an easy job once the air inlet pipe is removed but looks like a major PITA.
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Old Aug 8, 2020 | 09:49 AM
  #45  
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Originally Posted by zzz4
Mine just sprung a leak at the plastic part that's bolted on the engine on the driver side. Parked the car OK, and then it just started spraying coolant on the exhaust pipe and splattering it everywhere.

I was hoping it would be an easy job once the air inlet pipe is removed but looks like a major PITA.
if you have worked on cars before, its relatively easy. Use a 1/4 ratchet for nearly every hard to get to bold.. go at the bolt on the turbo from the front of engine not from the top
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Old Aug 9, 2020 | 05:47 PM
  #46  
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have struggled to remove the lower bolt on part A2782002551. Spent a couple of hours trying to get the socket on the bolt head. Tried from every angle, no luck

Since it's the upper plastic part is broken, I'll probably remove the good piece from the new part and make my own part without messing with the lower bolt.
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Old Aug 11, 2020 | 09:54 AM
  #47  
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Old Aug 11, 2020 | 09:58 AM
  #48  
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This is on the driver's side. The top 3-way plastic pipe was deteriorated and two of the outlets just crumbled away. To remove the part, I need to somehow remove the bolt at the bottom where the aluminum pipe connects to the engine and pry it away. Earlier it was sdaid that the bolt holds two pipes togeter and I'm hoping my problem pipe is above the other one, otherwise I will have to unhook both of them which has the potential of breaking more things
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Old Jan 15, 2023 | 09:36 PM
  #49  
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Originally Posted by rickyanalog
So in my previous post, I was not able to tell what part number it was that was broke. I knew it was a coolant hose, but it turned out it was actually 2 different hoses. The part numbers are 278-200-09-00 and 278-200-10-00. One of them is the coolant hose for the turbocharger. Now the REAL problem begins.I can not for the life of me figure out how to get these 2 hoses out. I have removed the driver side wheel and fender in hopes of being able to access them from there. But there is a metal heat shield completely blocking access. I removed the skirt from underneath front end thinking maybe I would have a better shot from there, and nope. I'm really stuck here and any help would be greatly appreciated.



I've cuted a hole of 3" thru the heat shield.

This is the view from the driver side.
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