SL/R129: My SL500 seems to run cold - unusual?
Thread Starter
Newbie
Joined: Dec 2010
Posts: 14
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1996 SL500
My SL500 seems to run cold - unusual?
Howdy, from Colorado.
I’m new to SL ownership, having just purchased a 1996 SL500 - and I simply love the car. I have noticed however, that on fast and long runs (between 75 and 85 mph) on a cold day the car’s temperature refuses to climb above the second hash mark, which I believe is only 60 degrees Celsius. When I say a ‘cold day’, I am only talking about 30 degrees Fahrenheit (about 0 degrees Celsius) and certainly this is not an extreme situation for the cooling system or engine…
Of course there is a relationship between engine wear and engine temperature (an engine runs most efficiently and with less internal friction when at normal operating temperature) so I’m slightly concerned that such a low coolant temp might increase stress on the engine, etc… Otherwise the coolant temp seems to function normally and as expected, although I have yet to drive the car in any hot weather, and so cannot reliably comment as to the correct workings of the thermostat in the opposite extreme.
I’d like to know if this low temperature reading is normal for an SL500 under these conditions, or perhaps I should investigate this further…? Thanks so much in advance for any replies!
I’m new to SL ownership, having just purchased a 1996 SL500 - and I simply love the car. I have noticed however, that on fast and long runs (between 75 and 85 mph) on a cold day the car’s temperature refuses to climb above the second hash mark, which I believe is only 60 degrees Celsius. When I say a ‘cold day’, I am only talking about 30 degrees Fahrenheit (about 0 degrees Celsius) and certainly this is not an extreme situation for the cooling system or engine…
Of course there is a relationship between engine wear and engine temperature (an engine runs most efficiently and with less internal friction when at normal operating temperature) so I’m slightly concerned that such a low coolant temp might increase stress on the engine, etc… Otherwise the coolant temp seems to function normally and as expected, although I have yet to drive the car in any hot weather, and so cannot reliably comment as to the correct workings of the thermostat in the opposite extreme.
I’d like to know if this low temperature reading is normal for an SL500 under these conditions, or perhaps I should investigate this further…? Thanks so much in advance for any replies!
Newbie
Joined: Jan 2011
Posts: 11
Likes: 0
From: Azle Texas
06 230 chassis
something measuring and or relaying the info is not correct. These cars do not run that cool, it's a big v8 with an average to undersized radiator. The gauge itself behind the plastic screen would be suspect # 1 but the easier one of the two is the temp gage itself on the radiator or the water inlet on the engine, i bet it's one of those.
if you put two motors on a dyno at the same time(side by side) and ran both for 1 year, one at 130degrees and the other at 200degrees, the hotter motor would pass more post engine tare-down inspections than the one that ran cold/cool. cool/cold engine oil doesn't start working til about 190(ish) degrees.
if you put two motors on a dyno at the same time(side by side) and ran both for 1 year, one at 130degrees and the other at 200degrees, the hotter motor would pass more post engine tare-down inspections than the one that ran cold/cool. cool/cold engine oil doesn't start working til about 190(ish) degrees.
