SL/R230: Loosing Coolant SOS
08-08-2014, 05:09 PM
#1
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Loosing Coolant SOS
Hoping some of you can chime in on a possible solution.
Subject: 2005, SL55, 50k miles
The car is mechanically stock. I recently started losing coolant every couple days. Enough to trip the light, resulting in 1-2 liter top offs to resolve the issue. Last weekend I got out there to try and find the source. I see no signs of leaking coolant on the outside of the reservoir, radiator, hoses, and motor, and no puddles under the car when parked. The bad news is I see what looks like some sort of lubricant mixing with the coolant. The reservoir bottle had a cream colored jello type substance present. My first guess is motor Oil....
or possibly transmission fluid.
I Dropped the car off for service, my Indi takes samples of motor oil and trans fluid but sees no sign of coolant in either. They pressure tested the cooling system over night, and it held pressure. At this point they are inclined to think it’s some O-ring in the oil cooling system near the oil filter or head gasket(s). I Was hoping for a sanity check on either. Head gaskets seems really out of character to me on this motor.
Thanks for the feedback,
-Audio
Subject: 2005, SL55, 50k miles
The car is mechanically stock. I recently started losing coolant every couple days. Enough to trip the light, resulting in 1-2 liter top offs to resolve the issue. Last weekend I got out there to try and find the source. I see no signs of leaking coolant on the outside of the reservoir, radiator, hoses, and motor, and no puddles under the car when parked. The bad news is I see what looks like some sort of lubricant mixing with the coolant. The reservoir bottle had a cream colored jello type substance present. My first guess is motor Oil....
or possibly transmission fluid. I Dropped the car off for service, my Indi takes samples of motor oil and trans fluid but sees no sign of coolant in either. They pressure tested the cooling system over night, and it held pressure. At this point they are inclined to think it’s some O-ring in the oil cooling system near the oil filter or head gasket(s). I Was hoping for a sanity check on either. Head gaskets seems really out of character to me on this motor.
Thanks for the feedback,
-Audio
08-28-2014, 05:22 PM
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06 SL65AMG, 13 Tesla Model S 60kwh, 02 Jaguar S-Type 3.0, 12 S550 4 Matic, 07 E320 Bluetec, 06 LX470
I would check if its a blown head gasket cause if your not seeing leaks or puddles and lubricant is mixing with coolant then that's not a good sign
08-28-2014, 11:03 PM
#4
With the car running place your hand right up to each exhaust tip(s) and then smell your hand. If it smells sweet there is coolant burning in the cylinder indicating a bad head gasket.
Turn on the defroster with the heat set high and the windows all closed. Does the windshield fog up? If so you likely have a bad heater core. You can also feel the carpet around the firewall/trans tunnel area near the pedals/pass foot well. Either of these conditions indicate a leaking heater core. This is also uncharacteristic of these cars with your mileage.
Either of these you can do at home.
It will be interesting to hear what you finally find.
Turn on the defroster with the heat set high and the windows all closed. Does the windshield fog up? If so you likely have a bad heater core. You can also feel the carpet around the firewall/trans tunnel area near the pedals/pass foot well. Either of these conditions indicate a leaking heater core. This is also uncharacteristic of these cars with your mileage.
Either of these you can do at home.
It will be interesting to hear what you finally find.
08-31-2014, 06:11 PM
#5
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Also, many independent repair shops can check for exhaust gas in the coolant by connecting an instrument to the coolant expansion tank cap. The equipment "sniffs" the fumes in the coolant to detect carbon monoxide or other fumes. Presence of these indicates a leaking head gasket which may allow coolant to seep into a cylinder (or lead to rapid overheating of the coolant by the hot exhaust gasses.)
