Coolant Leak (‘95 C36)
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Coolant Leak (‘95 C36)
Hey Guys,
This has been going on for over a 1yr now, but is getting progressively worse. I filled the reservoir about 400-500 miles ago and it dropped over 1/2. The warning light illuminated earlier - it was over 90f in VA today. I rarely drive the car, there are no visible leaks underneath but it could be dripping on the splash guard.
I had the water pump replaced @ 110k and the car is currently at 145k. The system was pressure checked a few yrs back and passed. The oil looks fine and no contamination in the coolant reservoir. The car cools w/ no issues. The original head gasket was replaced under the factory warranty @ 52k. I swapped out the reservoir cap a month or so ago w/ a genuine replacement . I parked the car on an incline, cranked the heat up, and followed the proper procedure for burping the system. I believe the radiator is original..
I would be interested in hearing where you guys would start to trace the leak? Thanks!!
-Rob
This has been going on for over a 1yr now, but is getting progressively worse. I filled the reservoir about 400-500 miles ago and it dropped over 1/2. The warning light illuminated earlier - it was over 90f in VA today. I rarely drive the car, there are no visible leaks underneath but it could be dripping on the splash guard.
I had the water pump replaced @ 110k and the car is currently at 145k. The system was pressure checked a few yrs back and passed. The oil looks fine and no contamination in the coolant reservoir. The car cools w/ no issues. The original head gasket was replaced under the factory warranty @ 52k. I swapped out the reservoir cap a month or so ago w/ a genuine replacement . I parked the car on an incline, cranked the heat up, and followed the proper procedure for burping the system. I believe the radiator is original..
I would be interested in hearing where you guys would start to trace the leak? Thanks!!
-Rob
Last edited by RPB; May 20, 2018 at 07:44 PM.
Thread Starter
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Joined: Sep 2007
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Thread Starter
Super Member
Joined: Sep 2007
Posts: 754
Likes: 12
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I’m pretty sure my heater core is not the culprit. My car is not displaying any of the symptoms. The last time I ran the heat was a few months ago, but when I did there were no issues.
I can never wrap my head around why some choose to respond w/ the worst case scenario first?!
I wish things were the opposite.
I can never wrap my head around why some choose to respond w/ the worst case scenario first?!
I wish things were the opposite.Last edited by RPB; May 21, 2018 at 01:04 AM.
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From: Land of mountains, cheese, chocolate and watches
12' W204 C63 AMG coupe "T-Rex", 12' W451 Smart Fortwo Pulse (99' W202 C43 AMG + Ultima Can-Am sold)
Do you have antifreeze in the system? Hairline crack on the expansion tank perhaps, but you would see the source normally and easily if antifreeze is present in the cooling mix.
If you can't find any traces, I would think the head gasket in the combustion area as you don't have oil contamination.
If you can't find any traces, I would think the head gasket in the combustion area as you don't have oil contamination.
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From: PDX
1999 C43, 2008 P30 E63, 2014 SQ5, 2024 Model Y Performance
I’m pretty sure my heater core is not the culprit. My car is not displaying any of the symptoms. The last time I ran the heat was a few months ago, but when I did there were no issues.
I can never wrap my head around why some choose to respond w/ the worst case scenario first?! I wish things were the opposite.
I can never wrap my head around why some choose to respond w/ the worst case scenario first?!
I wish things were the opposite.
Thread Starter
Super Member
Joined: Sep 2007
Posts: 754
Likes: 12
...
You already listed no visible leaks, a new water pump, pressure test, no contamination in the coolant, no cooling issues, replaced head gasket, new reservoir cap, and burping the system. The only thing I didn't see was the heater core. It would explain why the coolant level is low and you can't find a leak. Check the passenger side floor board for moisture. Besides, wouldn't the worst case scenario be a blown head gasket?? All a faulty heater core will do is damage your carpet...
I topped off the coolant last night and burped the system. No apparent loss so far after driving today, it prob would be best to get the system pressure checked.
Thanks.
Last edited by RPB; May 21, 2018 at 10:14 PM.
