coolant loss after changing, proper operating temp
02-16-2008, 06:37 PM
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1991 300E 63K miles in Ice Blue
coolant loss after changing, proper operating temp
so, after changing my coolant and other fluids I am getting some loss on garage floor, with no overheating however my temp gauge is just slightly over 80*C
I read it is supposed to be near 100 at normal operating temps... but heat and a/c working properly just the windshield res seems so hot even though I realize it is heated by design... Its hotter that the expansion tank and significantly so.
I have looked and cant see where the fluid is originating but the car is new to me but highly dealership maintained '91 with 63K
Any ideas?
I read it is supposed to be near 100 at normal operating temps... but heat and a/c working properly just the windshield res seems so hot even though I realize it is heated by design... Its hotter that the expansion tank and significantly so.
I have looked and cant see where the fluid is originating but the car is new to me but highly dealership maintained '91 with 63K
Any ideas?
02-16-2008, 08:37 PM
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'98 S500
Take a look at the radiator cap.
I had three problems at once; water pump failure, hidden radiator cap failure, and hidden elbow fitting failure. The small hose connecting the top of the radiator to the expansion tank is listed as part# 0005000894, "90 Degree Elbow Fitting on Top of Radiator for Drain Hose" on AutohausAZ.com
Water pump failed in predictable fashion: bearing failure with leaking water.
Radiator cap was undetected until I inadvertantly snapped the 'cap' off the valve section.
The elbow failed by losing one of its 'legs' and eventually blew out of the radiator, emptying the coolant in a vey messy fashion.
Water loss and temp have not been a problem since replacement of all three.
Hope this helps.
PS If I had known, I would have replaced the elbow the day I bought the car (155,000 mi). Cheap, simple, and quick repair. Failure mode is sudden catastraphic loss of all coolant - a car stranding situation.
Water pump failed in predictable fashion: bearing failure with leaking water.
Radiator cap was undetected until I inadvertantly snapped the 'cap' off the valve section.
The elbow failed by losing one of its 'legs' and eventually blew out of the radiator, emptying the coolant in a vey messy fashion.
Water loss and temp have not been a problem since replacement of all three.
Hope this helps.
PS If I had known, I would have replaced the elbow the day I bought the car (155,000 mi). Cheap, simple, and quick repair. Failure mode is sudden catastraphic loss of all coolant - a car stranding situation.
02-17-2008, 12:32 AM
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1991 300E 63K miles in Ice Blue
checked these 3
hmmmm, thanks for the suggestions
My expansion tank cap looks brand new as does the seal and the coolant is not overflowing from the expansion tank... Waterpump is not making any unusual noises and I cant see any coolant coming from there but not positive about the underside, and the elbow seems fine too.
My expansion tank cap looks brand new as does the seal and the coolant is not overflowing from the expansion tank... Waterpump is not making any unusual noises and I cant see any coolant coming from there but not positive about the underside, and the elbow seems fine too.
02-17-2008, 08:02 AM
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2010 VW Golf TDI
My water pump went at about 67K. It started slow, but became much worse rather quickly. When it is bad, it is easy to see leaking from the source. I had all hoses replaced, thermostat replaced, radiator flushed, and the serpentine belt replaced when they did the water pump. I would recommend the same thing for you.
I also had a bad cap on the expansion tank. I would get a sucked in radiator hose and also lose a little fluid. The new cap fixed the problem.
I also had the plastic elbow break. In fact I think they broke it when they flushed the radiator. For mine, a little piece that broke was never found. It may be sitting in the radiator or maybe it was flushed out. It was never found.
I forgot to look where you are located, but if you are in a cold climate it may not be unusual to run just over 80 degrees when cruising. It will go up when you slow down in stop and go traffic and it will likely climb to 100+ when the weather gets hot outside.
Wow!!! Hawaii!!! You live in paradise!!!
My car ran a bit cooler until they replaced the thermostat. I think the consensus was that an old thermostat can be stuck partially open. They can also fail closed, so it was recommended to keep the new one, even though I rather liked running cooler. Now I have a "CoolHarness" from another forum member that starts my auxiliary fans at a lower temperature. Now they come on at 95 degrees instead of about 105 or more. The cool harness keeps me from going over 100 degrees during hot weather. I was worried that temperatures of 110 degrees and then cooling rather rapidly to about 87 degrees over and over again would contribute to problems with my failing head gasket. I seem to be in a holding pattern with my head gasket right now, so maybe it is working.
The running temperature of these cars is always a topic of concern when the weather gets hot. I know you didn't complain about high temps in your post, but it is good to be aware of the issues. They tend to run pretty hot in hot weather and there are multiple systems that come into play to maintain the proper temperature. Part of it is the 87 degree thermostat, part of it is the low speed fans that cycle due to signals from the AC system pressure, and part of it is the auxiliary fans that come on at high speed at about 105 degrees. If your AC is out of whack, low on charge for example, then that can contribute to higher temps. Also there are some fuses for the auxiliary fans that can be an issue. they are the same fans, but they come on at high speed when the car gets too hot. They cycle at lower speeds to cope with the AC pressure issues.
I also had a bad cap on the expansion tank. I would get a sucked in radiator hose and also lose a little fluid. The new cap fixed the problem.
I also had the plastic elbow break. In fact I think they broke it when they flushed the radiator. For mine, a little piece that broke was never found. It may be sitting in the radiator or maybe it was flushed out. It was never found.
I forgot to look where you are located, but if you are in a cold climate it may not be unusual to run just over 80 degrees when cruising. It will go up when you slow down in stop and go traffic and it will likely climb to 100+ when the weather gets hot outside.
Wow!!! Hawaii!!! You live in paradise!!!
My car ran a bit cooler until they replaced the thermostat. I think the consensus was that an old thermostat can be stuck partially open. They can also fail closed, so it was recommended to keep the new one, even though I rather liked running cooler. Now I have a "CoolHarness" from another forum member that starts my auxiliary fans at a lower temperature. Now they come on at 95 degrees instead of about 105 or more. The cool harness keeps me from going over 100 degrees during hot weather. I was worried that temperatures of 110 degrees and then cooling rather rapidly to about 87 degrees over and over again would contribute to problems with my failing head gasket. I seem to be in a holding pattern with my head gasket right now, so maybe it is working.
The running temperature of these cars is always a topic of concern when the weather gets hot. I know you didn't complain about high temps in your post, but it is good to be aware of the issues. They tend to run pretty hot in hot weather and there are multiple systems that come into play to maintain the proper temperature. Part of it is the 87 degree thermostat, part of it is the low speed fans that cycle due to signals from the AC system pressure, and part of it is the auxiliary fans that come on at high speed at about 105 degrees. If your AC is out of whack, low on charge for example, then that can contribute to higher temps. Also there are some fuses for the auxiliary fans that can be an issue. they are the same fans, but they come on at high speed when the car gets too hot. They cycle at lower speeds to cope with the AC pressure issues.
Last edited by ksing44; 02-17-2008 at 08:21 AM.
