Engine Coolant Loss 2010 S550
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Junior Member
Joined: Aug 2007
Posts: 50
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From: Honolulu
2010 S550
Engine Coolant Loss 2010 S550
Last week I got a "Check Engine Coolant" message/alert displayed briefly after starting the car in the morning (engine as cold as it ever gets in Hawaii). After engine warmed the display cleared, engine temp normal and no indication of a problem throughout the day. Debated simply adding a little water, but decided to go with the MB recommended spec no. 325 (P/N Q1 03 0002) Anti-Corrosion/Antifreeze Agent from the local dealer for ~$38/gal.
It took about 0.8 quarts of fluid to bring the level just above the full (cool) tab in the surge tank.
Now I'm just wondering if its common to lose minor amounts of coolant over time? I've had the car 1.5 years, driven 75/25 city/highway) and 13,000 miles; one "A" service completed last December.
I did a search of the forums and the net and it didn't seem to be a common issue...
It took about 0.8 quarts of fluid to bring the level just above the full (cool) tab in the surge tank.
Now I'm just wondering if its common to lose minor amounts of coolant over time? I've had the car 1.5 years, driven 75/25 city/highway) and 13,000 miles; one "A" service completed last December.
I did a search of the forums and the net and it didn't seem to be a common issue...
MBWorld Fanatic!
Joined: Dec 2001
Posts: 3,430
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From: USA
W140 Mercedes S350, W221 S550 sport
Last week I got a "Check Engine Coolant" message/alert displayed briefly after starting the car in the morning (engine as cold as it ever gets in Hawaii). After engine warmed the display cleared, engine temp normal and no indication of a problem throughout the day. Debated simply adding a little water, but decided to go with the MB recommended spec no. 325 (P/N Q1 03 0002) Anti-Corrosion/Antifreeze Agent from the local dealer for ~$38/gal.
It took about 0.8 quarts of fluid to bring the level just above the full (cool) tab in the surge tank.
Now I'm just wondering if its common to lose minor amounts of coolant over time? I've had the car 1.5 years, driven 75/25 city/highway) and 13,000 miles; one "A" service completed last December.
I did a search of the forums and the net and it didn't seem to be a common issue...
It took about 0.8 quarts of fluid to bring the level just above the full (cool) tab in the surge tank.
Now I'm just wondering if its common to lose minor amounts of coolant over time? I've had the car 1.5 years, driven 75/25 city/highway) and 13,000 miles; one "A" service completed last December.
I did a search of the forums and the net and it didn't seem to be a common issue...
Also do I need a special kind if I just need to top off?
Last edited by Jason B; Nov 14, 2015 at 06:54 PM.
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Joined: Nov 2014
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From: Chicago burbs
2015 S550
You need to get the coolant up to the top of that plastic piece. Use the same color MB coolant that is in the car to top it off. The dealer sells a couple different kinds with different colors.
MBWorld Fanatic!
Joined: Dec 2001
Posts: 3,430
Likes: 187
From: USA
W140 Mercedes S350, W221 S550 sport
So you have to use "Mercedes coolant"? It's down probably only a half a cup, needs topped off. My guy at dealer said I could just put a little distilled water in
Last edited by Jason B; Nov 21, 2015 at 11:59 AM.
MBWorld Fanatic!
Joined: Nov 2014
Posts: 4,242
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From: Chicago burbs
2015 S550
It's a straight fill from what I understand. No mixing. Although I'm sure a little distilled water to top it off is fine.
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MBWorld Fanatic!
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Acura TL 2008 - Acura MDX 2012
Its about $1.99 for a gallon.
Newbie
Joined: Mar 2019
Posts: 1
Likes: 1
S550
2012 S550 w/ 74k . . . had to add coolant twice in past month. No evidence of leaks, just dash notification to "Check coolant level" . . . . thankfully the Dealer tops off at no cost!
Thnx Schumacher
Just wondering what issues may lay ahead ?? thnx All
Thnx Schumacher
Just wondering what issues may lay ahead ?? thnx All
Member
Joined: Feb 2008
Posts: 114
Likes: 10
From: Northern California
2009 S550
A while back I had a similar situation and it turned out the coolant was leaking into the washer fluid reservoir through the heating coil. No evidence of a leak since my washer fluid level was low at the time, so the reservoir was just filling up (unknown to me). You might want to take a look at that possibility.
Newbie
Joined: Feb 2020
Posts: 1
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2012 Mercedes S550
How did you replace it? I think I have same situation. Except now it’s leaking more
how did you fix it? Can you help me? Any videos on YouTube?
A while back I had a similar situation and it turned out the coolant was leaking into the washer fluid reservoir through the heating coil. No evidence of a leak since my washer fluid level was low at the time, so the reservoir was just filling up (unknown to me). You might want to take a look at that possibility.
