Sever coolant leak when I shut the car off - where is from?
Thread Starter
Junior Member
Joined: Jul 2012
Posts: 46
Likes: 3
From: Halifax, Nova Scotia Canada
W211 CDI
Sever coolant leak when I shut the car off - where is from?
Dear All:
All of a sudden, I got a coolant leak. Ironically, it does not leak when the car is running; but, as soon as I shut the car off, it starts leaking with a steady stream. I cannot figure out where it is coming from, at least when I look from both top and bottom , I cannot see the location of the leak. The coolant runs along the plastic channel piece that is below the radiator.
Any hint would be much appreciated.
Regards,
All of a sudden, I got a coolant leak. Ironically, it does not leak when the car is running; but, as soon as I shut the car off, it starts leaking with a steady stream. I cannot figure out where it is coming from, at least when I look from both top and bottom , I cannot see the location of the leak. The coolant runs along the plastic channel piece that is below the radiator.
Any hint would be much appreciated.
Regards,
MBWorld Fanatic!
Joined: Sep 2016
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From: TX
2023 GLE3502W, 2024 GLC3002W, 1967 Pontiac GTO 4 sp (sold...sniff)
I googled E320 overflow tank and got this. Could one of the small hoses under the tank come off? Worth a look.
http://www.carparts.com/details/Merc...E&gclsrc=aw.ds
http://www.carparts.com/details/Merc...E&gclsrc=aw.ds
Thread Starter
Junior Member
Joined: Jul 2012
Posts: 46
Likes: 3
From: Halifax, Nova Scotia Canada
W211 CDI
I have already checked that - no issue. The coolant seems to come on the lower levels (I think). Moreover, why should it start leaking form the reservoir, after I shut off the engine?!
Thanks very much for your comment, anyway.
Cheers,
Thanks very much for your comment, anyway.
Cheers,
MBWorld Fanatic!
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From: In the Shadow of the Tetons
2013 ML350 Bluetec
How stiff is your radiator hose after the car has been allowed to cool overnight? If there's still pressure in it, you might want to do a pressure test on the cooling system to see if you've got a blown head gasket. Other than that, I wonder if you've got a water pump going bad.
MBWorld Fanatic!
Joined: Sep 2016
Posts: 1,189
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From: TX
2023 GLE3502W, 2024 GLC3002W, 1967 Pontiac GTO 4 sp (sold...sniff)
How stiff is your radiator hose after the car has been allowed to cool overnight? If there's still pressure in it, you might want to do a pressure test on the cooling system to see if you've got a blown head gasket. Other than that, I wonder if you've got a water pump going bad.
MBWorld Fanatic!
Joined: Sep 2016
Posts: 1,189
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From: TX
2023 GLE3502W, 2024 GLC3002W, 1967 Pontiac GTO 4 sp (sold...sniff)
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MBWorld Fanatic!
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From: In the Shadow of the Tetons
2013 ML350 Bluetec
If that's the case, then a pressure test on the cooling system will allow you to see where the coolant is being pushed from. Take the bottom plastic panels off, pressurize the system, and start looking closely.
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From: s.f. bay area
s500 GL450 GL63 Z71XL Yukon 67 396 SS velle 68 Vert Camaro 69 RSSS Vert Camaro 75 Blazer
Faridtaheri, Coolant systems still have pressure after you shut off the motor if the motor is in normal operating temperatures because the coolant expands when hot. Make sure you do not overfill the overflow reservoir/expansion tank when it is hot. You are almost guaranteed to have it leak out the excess. When you shut of the motor, the engine actually gets a little hotter because the coolant is no longer flowing and not cooling down and it builds up pressure.
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From: V E G A S
1922 Ford Model T / no OBD
Coolant pump would be my first suspect.
With pump turning the centrifugal force keeps coolant out of shaft seal, but when the engine stops, it will pour via bad seal.
Bottom of the pump housing has small drainage hole. Try to get to it, or stick your phone camera to confirm.
Leak will have washed out dirt in the area.
With pump turning the centrifugal force keeps coolant out of shaft seal, but when the engine stops, it will pour via bad seal.
Bottom of the pump housing has small drainage hole. Try to get to it, or stick your phone camera to confirm.
Leak will have washed out dirt in the area.
Thread Starter
Junior Member
Joined: Jul 2012
Posts: 46
Likes: 3
From: Halifax, Nova Scotia Canada
W211 CDI
OK! I will definitely check the coolant pump (same as water pump I hope?!).
However, I had a leak on my Beemer's water pump, but, that was leaking all the time, not when only engine gets shut off! In any case, I will investigate the pump.
Cheers,
Farid
However, I had a leak on my Beemer's water pump, but, that was leaking all the time, not when only engine gets shut off! In any case, I will investigate the pump.
Cheers,
Farid
MBWorld Fanatic!
Joined: Jan 2009
Posts: 9,224
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From: V E G A S
1922 Ford Model T / no OBD
That reminds me the old joke that the same brush can be:
-toothbrush
-fingernail brush
-shoe cleaning brush.
But don't you dare to reverse the order.
