M-Class (W163) Produced 1998-2005: ML 230, ML 320, ML 350, ML 400 CDI, ML 430, ML 500, ML 270 CDI

98 W163 ML320 - Coolant leak at Reservoir

Old Jun 19, 2021 | 06:29 PM
  #1  
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From: northern ca
ml320 1998 w163
98 W163 ML320 - Coolant leak at Reservoir

Popped my hood to just to check things out fluid levels and it looks like a I have coolant leak on the Reservoir. Glad I looked :-)
Ordered a new Dorman Coolant Reservoir replacement.
Figured I would do a coolant flush for the first time. After reading AR20.00-P-1142HA instructions / watching a few youtubes, if I understand this correctly,
1. Drain the old coolant.
2. Replace reservoir.
3. Flush with distilled water. (Add distilled water. Heat up engine running heat on high for about 10 minutes. Let cool and drain again)
4. Add new blue coolant concentrate with a 50/50 mix to distilled water... 11L / about 3Gallons

So my questions:
Was going to go pickup Peak or Recochem blue concentrate if I can find in stock. Is there really any difference in coolants as long as it is rated European / Blue?
Any other gotchas that I should be aware of when replacing the reservoir?
Any gotchas about flushing the coolant?
Thank you!
Scr

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Old Jun 20, 2021 | 07:19 AM
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The coolant capacity is 12.7 US qts. Buy Zerex G05 which comes in diluted or not diluted. Pick you choice but understand that the non-diluted must be 50-50.



https://shop.advanceautoparts.com/p/...cal&store=7286

Last edited by Maj. Dundee; Jun 20, 2021 at 07:35 AM.
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Old Jun 20, 2021 | 07:37 AM
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You should also drain the eng. completely by removing the drain ports on both sides of the eng. Proper Torx socket needed.

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Old Jun 20, 2021 | 09:55 AM
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Good morning Maj. Dundee. Thank you for the info.
Especially about draining the engine. I didn't see that in the instructions. I will do some more reading on that. I have the Torx but do you know the NM for re torquing?
Thanks!
Scr

Last edited by scottcruss; Jun 20, 2021 at 10:00 AM.
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Old Jun 21, 2021 | 05:08 AM
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Scroll down the PDF and see Torque Value below Step #24.

You will need two sealing rings and if you choose, you can also replace the two plugs. If one or both of the drain plugs removal does not drain, simply inert a small swrewdriver into the hole to clear the sediment.



Attached Files
File Type: pdf
Coolant Drain.pdf (219.6 KB, 115 views)

Last edited by Maj. Dundee; Jun 21, 2021 at 05:43 AM.
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Old Jun 22, 2021 | 07:54 PM
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A little help if possible... went to replace the old Coolant Reservoir and it had no cooling level sensor on it. New one has. There appears to be a cable wire tied in the back that would be for the sensor. Is this the cooling level sensor cable?
Thank you.


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Old Jun 22, 2021 | 08:32 PM
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Originally Posted by Maj. Dundee
Scroll down the PDF and see Torque Value below Step #24.

You will need two sealing rings....
Hey Mar Dundee, I have been searching and having trouble finding the sealing rings. Would the rings actually be the same copper gasket that the oil drain plug uses?
Thank you.
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Old Jun 23, 2021 | 05:32 AM
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The level sensor is built into the inside of the reservoir.
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Old Jun 23, 2021 | 05:34 AM
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Originally Posted by scottcruss
Hey Mar Dundee, I have been searching and having trouble finding the sealing rings. Would the rings actually be the same copper gasket that the oil drain plug uses?
Thank you.
I provided you with the part numbers. You must go to a dealer and purchase them.
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Old Jun 23, 2021 | 10:17 AM
  #10  
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Check here for the seal rings.

https://www.mercedespartswholesale.c...ing-1129970144
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Old Jun 23, 2021 | 12:11 PM
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Originally Posted by Maj. Dundee
The level sensor is built into the inside of the reservoir.
Thank you. I understand that about where the actual sensor is located. I more meant if that was the correct cable to connect to the sensor to be able to monitor since the prior one was not connected. I was hoping for confirmation since I have not found it detailed in any docs yet and I did not want to simply connect a cable and hope it is the correct one :-)

Originally Posted by Maj. Dundee
Thank you for sending me the link. I was asking about the part because I was having difficult searching for it based on the part #. There are a few places that I have gotten parts in the past but was unable to find. This really helps.
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Old Jun 24, 2021 | 04:12 PM
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It appears that my model does not support monitoring the Coolant Reservoir. The prior reservoir had no sensor on it and there appears to be no monitoring sensor cable that I can find. :-(
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