MAZDA CX5 was 130F, so still not warmed up enough to race it. ED
At what temp do "cold engine" lights go off?
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Originally Posted by 69GTX
At 100-130 deg F coolant temp following initial startup the engine oil is far from warmed up. Engine oil needs to get to 170-180 deg F....and typically lags coolant temperature. A few members did some self studies in the past and found that at moderate ambient temps of 45-65 deg F it would take 15-20 miles of driving or approx 15-20 min of time to fully warmup your engine oil. High revving when coolant temp is 130-160 deg F doesn't seem to make good sense....especially since the oil anti-corrosion/wear additives don't fully kick in until 170-180 deg F. For higher revving I'd rather see engine oil temp up around 195-215 deg F.
In my 2004 F150, the engine oil temp would never hit the desired temps you are looking for - even after driving for hours at temperatures below zero. Coolant temp would hold around 190, but the oil temp stayed at 180 or below. Oil temp might hit 160 after a 1/2 hour of very spirited driving.
Just one more data point that says one size fits all does not always work...
At 100-130 deg F coolant temp following initial startup the engine oil is far from warmed up. Engine oil needs to get to 170-180 deg F....and typically lags coolant temperature. A few members did some self studies in the past and found that at moderate ambient temps of 45-65 deg F it would take 15-20 miles of driving or approx 15-20 min of time to fully warmup your engine oil. High revving when coolant temp is 130-160 deg F doesn't seem to make good sense....especially since the oil anti-corrosion/wear additives don't fully kick in until 170-180 deg F. For higher revving I'd rather see engine oil temp up around 195-215 deg F.
In my 2004 F150, the engine oil temp would never hit the desired temps you are looking for - even after driving for hours at temperatures below zero. Coolant temp would hold around 190, but the oil temp stayed at 180 or below. Oil temp might hit 160 after a 1/2 hour of very spirited driving.
Just one more data point that says one size fits all does not always work...
I believe I have a Civic in the generation you're referring to. Because I have that light on mine instead of a temperature gauge.
Prior to this car I used to drive an 8th gen Civic with a standard temperature read out, I ended up giving that car away. Since I drive the same route with the newer car that I did with the older, I know where the temperature would be on the gauge relative to each car. You are correct that it's very close to cold temperature. The light goes out for me around the time the bar is roughly less than half of regular operating temperature. I could probably use my reader to see the exact temperature.
I obviously don't like the light because I don't know at which temperature it's going to turn red to tell me it's overheating. I'd rather know ASAP before it even gets close.
FYI: My understanding of why they replaced it is because people were waiting too long to "drive" the car waiting for it to warm up, waiting too long means less fuel economy or more pollution? Especially in colder months?
Prior to this car I used to drive an 8th gen Civic with a standard temperature read out, I ended up giving that car away. Since I drive the same route with the newer car that I did with the older, I know where the temperature would be on the gauge relative to each car. You are correct that it's very close to cold temperature. The light goes out for me around the time the bar is roughly less than half of regular operating temperature. I could probably use my reader to see the exact temperature.
I obviously don't like the light because I don't know at which temperature it's going to turn red to tell me it's overheating. I'd rather know ASAP before it even gets close.
FYI: My understanding of why they replaced it is because people were waiting too long to "drive" the car waiting for it to warm up, waiting too long means less fuel economy or more pollution? Especially in colder months?
Originally Posted by MNgopher
Originally Posted by 69GTX
At 100-130 deg F coolant temp following initial startup the engine oil is far from warmed up. Engine oil needs to get to 170-180 deg F....and typically lags coolant temperature. A few members did some self studies in the past and found that at moderate ambient temps of 45-65 deg F it would take 15-20 miles of driving or approx 15-20 min of time to fully warmup your engine oil. High revving when coolant temp is 130-160 deg F doesn't seem to make good sense....especially since the oil anti-corrosion/wear additives don't fully kick in until 170-180 deg F. For higher revving I'd rather see engine oil temp up around 195-215 deg F.
In my 2004 F150, the engine oil temp would never hit the desired temps you are looking for - even after driving for hours at temperatures below zero. Coolant temp would hold around 190, but the oil temp stayed at 180 or below. Oil temp might hit 160 after a 1/2 hour of very spirited driving.
Just one more data point that says one size fits all does not always work...
Even more reason for your truck to perform an extended oil warmup before applying higher revs of 3500-5500 rpm. At 160 deg your engine oil add pack might not even be fully functional after 30 min of normal driving. If it were my vehicle, I'd be blocking off 1/2-2/3 of the radiator during Jan-March to ensure my oil temp got up to 175-190 deg in a reasonable amount of time. My old 1968 Plymouth GTX had this issue and I blocked off 3/4 of the radiator for 12-20 mile exercise runs during the winter.
Originally Posted by 69GTX
At 100-130 deg F coolant temp following initial startup the engine oil is far from warmed up. Engine oil needs to get to 170-180 deg F....and typically lags coolant temperature. A few members did some self studies in the past and found that at moderate ambient temps of 45-65 deg F it would take 15-20 miles of driving or approx 15-20 min of time to fully warmup your engine oil. High revving when coolant temp is 130-160 deg F doesn't seem to make good sense....especially since the oil anti-corrosion/wear additives don't fully kick in until 170-180 deg F. For higher revving I'd rather see engine oil temp up around 195-215 deg F.
In my 2004 F150, the engine oil temp would never hit the desired temps you are looking for - even after driving for hours at temperatures below zero. Coolant temp would hold around 190, but the oil temp stayed at 180 or below. Oil temp might hit 160 after a 1/2 hour of very spirited driving.
Just one more data point that says one size fits all does not always work...
Even more reason for your truck to perform an extended oil warmup before applying higher revs of 3500-5500 rpm. At 160 deg your engine oil add pack might not even be fully functional after 30 min of normal driving. If it were my vehicle, I'd be blocking off 1/2-2/3 of the radiator during Jan-March to ensure my oil temp got up to 175-190 deg in a reasonable amount of time. My old 1968 Plymouth GTX had this issue and I blocked off 3/4 of the radiator for 12-20 mile exercise runs during the winter.
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Originally Posted by NoNameJoe
I obviously don't like the light because I don't know at which temperature it's going to turn red to tell me it's overheating. I'd rather know ASAP before it even gets close.
I've had a gauge come in handy before. It was my 1995 Integra GS-R and I was stuck in bumper to bumper traffic on a freeway. I'm pretty sure my radiator fan wasn't turning on. I didn't hear it and the coolant temp gauge kept on rising past the usual regulated point. It was also about 85°F outside, but I turned off the A/C and switched the heat to max on maximimum fan. Kept it from going to red when I was stopped, which could be minutes at a time in that traffic. As soon as I got moving even 15 MPH the coolant temp was back to normal until I had to stop.
Not sure what happened, but I never experienced the fan not working after that up to the point where I turned over the car to my insurance company.
I obviously don't like the light because I don't know at which temperature it's going to turn red to tell me it's overheating. I'd rather know ASAP before it even gets close.
I've had a gauge come in handy before. It was my 1995 Integra GS-R and I was stuck in bumper to bumper traffic on a freeway. I'm pretty sure my radiator fan wasn't turning on. I didn't hear it and the coolant temp gauge kept on rising past the usual regulated point. It was also about 85°F outside, but I turned off the A/C and switched the heat to max on maximimum fan. Kept it from going to red when I was stopped, which could be minutes at a time in that traffic. As soon as I got moving even 15 MPH the coolant temp was back to normal until I had to stop.
Not sure what happened, but I never experienced the fan not working after that up to the point where I turned over the car to my insurance company.
The blue cold engine light in my Subaru OB only goes on in the winter. It takes a few miles at least for it to go off.
Originally Posted by 69GTX
Even more reason for your truck to perform an extended oil warmup before applying higher revs of 3500-5500 rpm. At 160 deg your engine oil add pack might not even be fully functional after 30 min of normal driving. If it were my vehicle, I'd be blocking off 1/2-2/3 of the radiator during Jan-March to ensure my oil temp got up to 175-190 deg in a reasonable amount of time. My old 1968 Plymouth GTX had this issue and I blocked off 3/4 of the radiator for 12-20 mile exercise runs during the winter.
I think you are missing the point: even under normal hot summer conditions, the oil temp barely would hit the temps you indicate are required. Expecting that blocking a portion of the radiator will cause it to get that hot in the dead of winter, when it can't even get there easy in the summer is a stretch.
Couple of things:
In the dead of summer, the oil temp virtually never hit 190. The vast majority of the time it might hit 180, even in 90+ degree temps. The only time you would see higher temps is when you loaded the thing up (like pulling a trailer), and then it still never went much past 190. The engine had a decent sized sump (7 quarts) that was exposed to a significant amount of airflow beneath the truck (aka:not through the radiator openings). Even in the dead of summer with lots of runs 1/2 hour to and hour, the oil temp often did not hit 170.
Should I still have been blocking off the radiator in the summer?
Also, your months are off for the climate here; November is actually as cold or colder than March here... so it would be 5 months of blocked radiators. To be blunt, not what anyone does here. Engines are not grenading all over the place as a result.
Even more reason for your truck to perform an extended oil warmup before applying higher revs of 3500-5500 rpm. At 160 deg your engine oil add pack might not even be fully functional after 30 min of normal driving. If it were my vehicle, I'd be blocking off 1/2-2/3 of the radiator during Jan-March to ensure my oil temp got up to 175-190 deg in a reasonable amount of time. My old 1968 Plymouth GTX had this issue and I blocked off 3/4 of the radiator for 12-20 mile exercise runs during the winter.
I think you are missing the point: even under normal hot summer conditions, the oil temp barely would hit the temps you indicate are required. Expecting that blocking a portion of the radiator will cause it to get that hot in the dead of winter, when it can't even get there easy in the summer is a stretch.
Couple of things:
In the dead of summer, the oil temp virtually never hit 190. The vast majority of the time it might hit 180, even in 90+ degree temps. The only time you would see higher temps is when you loaded the thing up (like pulling a trailer), and then it still never went much past 190. The engine had a decent sized sump (7 quarts) that was exposed to a significant amount of airflow beneath the truck (aka:not through the radiator openings). Even in the dead of summer with lots of runs 1/2 hour to and hour, the oil temp often did not hit 170.
Should I still have been blocking off the radiator in the summer?
Also, your months are off for the climate here; November is actually as cold or colder than March here... so it would be 5 months of blocked radiators. To be blunt, not what anyone does here. Engines are not grenading all over the place as a result.
Is the oil being heated up to higher temperatures at critical points like the cylinder wall piston area and then cooled off as it circulates only to hit that higher temperature on the next cycle, whatever that is?
In other words, will the oil temperature vary depending on the location in the engine?
In other words, will the oil temperature vary depending on the location in the engine?
Originally Posted by PimTac
Is the oil being heated up to higher temperatures at critical points like the cylinder wall piston area and then cooled off as it circulates only to hit that higher temperature on the next cycle, whatever that is?
In other words, will the oil temperature vary depending on the location in the engine?
Yes! The oil is essentially the coolant for the lower part of the engine. It's expected and relied upon to carry heat away from critical parts and dissipate it from the pan, or an oil cooler if one is installed. This oil-as-coolant function is especially critical in air-cooled engines, relatively rare on the streets today, but still common in aviation. It's no less important, however in liquid cooled engines, wherever they may be found.
Is the oil being heated up to higher temperatures at critical points like the cylinder wall piston area and then cooled off as it circulates only to hit that higher temperature on the next cycle, whatever that is?
In other words, will the oil temperature vary depending on the location in the engine?
Yes! The oil is essentially the coolant for the lower part of the engine. It's expected and relied upon to carry heat away from critical parts and dissipate it from the pan, or an oil cooler if one is installed. This oil-as-coolant function is especially critical in air-cooled engines, relatively rare on the streets today, but still common in aviation. It's no less important, however in liquid cooled engines, wherever they may be found.
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Originally Posted by 69GTX
At 100-130 deg F coolant temp following initial startup the engine oil is far from warmed up. Engine oil needs to get to 170-180 deg F.... High revving when coolant temp is 130-160 deg F doesn't seem to make good sense....especially since the oil anti-corrosion/wear additives don't fully kick in until 170-180 deg F. For higher revving I'd rather see engine oil temp up around 195-215 deg F.
Not necessary. Locally the oil temp will be higher and any EP will be activated in HTHS conditions in a passenger car - not a race car ( different rules there.) Me? I refrain from high revving/high load until my oil temp is above ~160F. Actually on the 85 cu.in. VW turbo, there is no high revving Only super high load at mid rpms. Poor little engine crammed with 18psi forced to act like a 3 litre.
At 100-130 deg F coolant temp following initial startup the engine oil is far from warmed up. Engine oil needs to get to 170-180 deg F.... High revving when coolant temp is 130-160 deg F doesn't seem to make good sense....especially since the oil anti-corrosion/wear additives don't fully kick in until 170-180 deg F. For higher revving I'd rather see engine oil temp up around 195-215 deg F.
Not necessary. Locally the oil temp will be higher and any EP will be activated in HTHS conditions in a passenger car - not a race car ( different rules there.) Me? I refrain from high revving/high load until my oil temp is above ~160F. Actually on the 85 cu.in. VW turbo, there is no high revving Only super high load at mid rpms. Poor little engine crammed with 18psi forced to act like a 3 litre.
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