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Oil Teperature v Engine wear graph?
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Originally Posted By: mitsuman47
Edit: Found it. It was an oil pan heater. And it looks like the Fe was the only thing that improved.
Jetta with oil pan heater
Nitpicking, since I myself have been nitpicked to death, the visc on the last two UOA's ..the ones showing the reduction, is 2cSt lower than the previous 4. While I'd like to lean toward the oil warmer being responsible, we're kinda left with a hole there for data to escape or enter through.
..but it's "evidence" none the less.
Thanks for that.
Edit: Found it. It was an oil pan heater. And it looks like the Fe was the only thing that improved.
Jetta with oil pan heater
Nitpicking, since I myself have been nitpicked to death, the visc on the last two UOA's ..the ones showing the reduction, is 2cSt lower than the previous 4. While I'd like to lean toward the oil warmer being responsible, we're kinda left with a hole there for data to escape or enter through.
..but it's "evidence" none the less.
Thanks for that.
Originally Posted By: Gary Allan
Originally Posted By: mitsuman47
Edit: Found it. It was an oil pan heater. And it looks like the Fe was the only thing that improved.
Jetta with oil pan heater
Nitpicking, since I myself have been nitpicked to death, the visc on the last two UOA's ..the ones showing the reduction, is 2cSt lower than the previous 4. While I'd like to lean toward the oil warmer being responsible, we're kinda left with a hole there for data to escape or enter through.
..but it's "evidence" none the less.
Thanks for that.
The Guy lives in Florida for crying out loud!
If he was going to go to all that trouble, he could have at least moved to Winnepeg!
Originally Posted By: mitsuman47
Edit: Found it. It was an oil pan heater. And it looks like the Fe was the only thing that improved.
Jetta with oil pan heater
Nitpicking, since I myself have been nitpicked to death, the visc on the last two UOA's ..the ones showing the reduction, is 2cSt lower than the previous 4. While I'd like to lean toward the oil warmer being responsible, we're kinda left with a hole there for data to escape or enter through.
..but it's "evidence" none the less.
Thanks for that.
The Guy lives in Florida for crying out loud!
If he was going to go to all that trouble, he could have at least moved to Winnepeg!
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Yeah ..the nerve... It would seem that he would promote either the additive activation or the visc schools of thought ..both maybe. His fuel enrichment influence should be very small assuming enough trip duration.
Heat activated additives like zinc [ZDDP] need heat and pressure to initially deposit their sacrificial film. After that, it is replenished only if it is worn off/destroyed.
This is a problem with camshaft /lifter surfaces, and only on a few engines. And only if they are run hard.
Of course, break in needs more additives.
But the temperature/wear testing was not about breaking in engines.
I still can't see where warm oil would not give as good or better protection in an engine that hot oil.
This is a problem with camshaft /lifter surfaces, and only on a few engines. And only if they are run hard.
Of course, break in needs more additives.
But the temperature/wear testing was not about breaking in engines.
I still can't see where warm oil would not give as good or better protection in an engine that hot oil.
Gary,
I would volunteer for the block heater test, but I don't think my data would be of much use. I don't have any UOA's in the winter without the block heater being used, and since I drive over 1 hour each way to work and back, the data wouldn't be very representative of the reduction in fuel enrichment stage.
Also keep in mind (and I'm sure you may have thought of this already) that the block heater is not thermostatically controlled. It simply heats on full tilt until it's unplugged. Thus, coolant temps will be significantly higher after a summer night than a winter night. Might still not give us the required results. I think someone who drives short trips should UOA over a winter with no block heater, then repeat the following winter with a block heater. Might be the only way to test this theory with some sort of accuracy.
Mechtech2,
I don't think it's warm oil that we have to worry about, but cold oil from a cold start-up is another story. I think the wear difference from having 170F oil to 200F oil is negligible compared to the difference from 40F to 200F. And this heating process in an engine without a heat exchanger could take up to 20 minutes. On my Altima (according to people on the forums that have measured their oil temps), the oil heats up in less than 10 minutes most of the time (it's factory equipped with a heat exchanger on all V6 models).
I would volunteer for the block heater test, but I don't think my data would be of much use. I don't have any UOA's in the winter without the block heater being used, and since I drive over 1 hour each way to work and back, the data wouldn't be very representative of the reduction in fuel enrichment stage.
Also keep in mind (and I'm sure you may have thought of this already) that the block heater is not thermostatically controlled. It simply heats on full tilt until it's unplugged. Thus, coolant temps will be significantly higher after a summer night than a winter night. Might still not give us the required results. I think someone who drives short trips should UOA over a winter with no block heater, then repeat the following winter with a block heater. Might be the only way to test this theory with some sort of accuracy.
Mechtech2,
I don't think it's warm oil that we have to worry about, but cold oil from a cold start-up is another story. I think the wear difference from having 170F oil to 200F oil is negligible compared to the difference from 40F to 200F. And this heating process in an engine without a heat exchanger could take up to 20 minutes. On my Altima (according to people on the forums that have measured their oil temps), the oil heats up in less than 10 minutes most of the time (it's factory equipped with a heat exchanger on all V6 models).
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But cylinder:ring interface is only briefly not at the boundary level of lubrication.
Not "knowing" the dynamics of the chemical reaction in the forming of the sacrificial compound, I'll speculate that the cylinder:ring wear is a mismatch between the depletion and the replenishing of the sacrificial layer due to reaction time at temp. Essentially, the colder it is, the longer it takes ..yet the demand is constant on a per stroke basis. I "imagine" that the much higher visc (due to temp) handles most of the other non-pressurized lube points.
Warm oil probably does protect just as good as hot oil. That too was alleged in Schneider's paper. After the 20 minute initial warming, partial cooled starts maintained virtually no wear. There you've got warm surfaces and warm oil. You're beyond the steepest part of the curve and more on the flattening plane part.
Again, I'm just doing a reconstruction of a dinosaur from a few pig's teeth. This is where my logic train takes me.
I'm more than happy to be spanked on the way I've connected the dots here. We do have challenges at isolating all the usual "speculative suspects" to assign them blame.
Not "knowing" the dynamics of the chemical reaction in the forming of the sacrificial compound, I'll speculate that the cylinder:ring wear is a mismatch between the depletion and the replenishing of the sacrificial layer due to reaction time at temp. Essentially, the colder it is, the longer it takes ..yet the demand is constant on a per stroke basis. I "imagine" that the much higher visc (due to temp) handles most of the other non-pressurized lube points.
Warm oil probably does protect just as good as hot oil. That too was alleged in Schneider's paper. After the 20 minute initial warming, partial cooled starts maintained virtually no wear. There you've got warm surfaces and warm oil. You're beyond the steepest part of the curve and more on the flattening plane part.
Again, I'm just doing a reconstruction of a dinosaur from a few pig's teeth. This is where my logic train takes me.
I'm more than happy to be spanked on the way I've connected the dots here. We do have challenges at isolating all the usual "speculative suspects" to assign them blame.
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It's in there somewhere. He quotes it a good bit.
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Quote:
Gary,
I would volunteer for the block heater test, but I don't think my data would be of much use. I don't have any UOA's in the winter without the block heater being used, and since I drive over 1 hour each way to work and back, the data wouldn't be very representative of the reduction in fuel enrichment stage.
The data would surely be diluted due to the % that you're out of fuel enrichment ..but I don't think it would be worthless. It should still show a decent reduction in the current noise level.
Quote:
Also keep in mind (and I'm sure you may have thought of this already) that the block heater is not thermostatically controlled. It simply heats on full tilt until it's unplugged.
Yeah ..it kinda mandates the use of a timer to work. You then experiment with 1/2 hour ..1 hour ..etc. until you get near op temp for the warmer months. On the lower end it wouldn't be too bad. Any warming will shorten or eliminate the fuel enrichment stage. I think most engines cut out at 160F. I would wonder if one had too big a warmer if convention cooling alone what temp one would reach in 75F+ as an ambient.
Gary,
I would volunteer for the block heater test, but I don't think my data would be of much use. I don't have any UOA's in the winter without the block heater being used, and since I drive over 1 hour each way to work and back, the data wouldn't be very representative of the reduction in fuel enrichment stage.
The data would surely be diluted due to the % that you're out of fuel enrichment ..but I don't think it would be worthless. It should still show a decent reduction in the current noise level.
Quote:
Also keep in mind (and I'm sure you may have thought of this already) that the block heater is not thermostatically controlled. It simply heats on full tilt until it's unplugged.
Yeah ..it kinda mandates the use of a timer to work. You then experiment with 1/2 hour ..1 hour ..etc. until you get near op temp for the warmer months. On the lower end it wouldn't be too bad. Any warming will shorten or eliminate the fuel enrichment stage. I think most engines cut out at 160F. I would wonder if one had too big a warmer if convention cooling alone what temp one would reach in 75F+ as an ambient.
Here's a more recent update on the Jetta with the oil pan heater with a few more data points: He added a bypass filter too:
http://www.bobistheoilguy.com/forums/ubb...226#Post1326226
http://www.bobistheoilguy.com/forums/ubb...339#Post1454339
I like this quote in the second thread:
Originally Posted By: Tornado Red
OCD, obsessive-compulsive disorder.
Symptoms include preheating engine oil when outside air temperatures drop below 70°F.
See also "Monk", TV series starring Tony Shaloub, for other examples of OCD behavior.
http://www.bobistheoilguy.com/forums/ubb...226#Post1326226
http://www.bobistheoilguy.com/forums/ubb...339#Post1454339
I like this quote in the second thread:
Originally Posted By: Tornado Red
OCD, obsessive-compulsive disorder.
Symptoms include preheating engine oil when outside air temperatures drop below 70°F.
See also "Monk", TV series starring Tony Shaloub, for other examples of OCD behavior.
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That was pretty funny. I have to get around to doing this myself. It will take a couple of years, but I've got enough "without" data to make any distinctive difference in results apparent. This is naturally under the qualifier that the data itself is inconclusive. I'll hope to only show highly suggestive data.
Coolant temps are far more stable then oil temps. First you have a radiator to help transfere heat fromt he water tot he air no such things for the oil in most applications. Second the coolant temp is stable because it is designed to be so by having excessive capacity for most applications. Because speeds inthe USA are low and their are few places where one can run all out for long legaly or illegaly oil capacity is not that great in many applications. WHen you look at purpose built race care's they normally have oil capacities measured in gallons not quarts. It is normally remote and a dry sump is used. They almost always have some form of oil cooling. Few road car's are like that. The ones that are are usualy models built in Europe and designed for long high speed cruiseing on one of the European Super HWY's.
Oil only functions as 20% of the cooling effort on a water cooled engine. The heat in the oil is based on load far more then the water coolant system.
Their is also a finite amount of heat that can be transfered tot he water and a limit to how fast youc an spin the water pump before cavatation occurs. This is why as load increase's the excessive heat that can not be taken up by the colling system has to go into the oil which is why you can see huge oil temp variations at wide open throttle and high loads but rather mild variations in the water temp.
Oil only functions as 20% of the cooling effort on a water cooled engine. The heat in the oil is based on load far more then the water coolant system.
Their is also a finite amount of heat that can be transfered tot he water and a limit to how fast youc an spin the water pump before cavatation occurs. This is why as load increase's the excessive heat that can not be taken up by the colling system has to go into the oil which is why you can see huge oil temp variations at wide open throttle and high loads but rather mild variations in the water temp.
I would be very interested to know the engine wear characteristics of coolant temperature vs oil temperature, but probably nobody out there knows for sure. Here is the coolant vs oil temp on a typical drive, you can see how the oil temperature really lags behind.
From the drive home today, dry-sump oil system:
Outside temp: 59 F
Startup:
Coolant temperature increased immediately, reaching 100 F within the first minute. Oil temperature remained at 66 F and showed no increase.
5 minutes:
This is how long it took for the oil temperature to budge, increasing to 68 F. Meanwhile the coolant reached 145 F.
10 minutes:
Coolant reached stable operating temperature of 196 F.
Oil was only 74 F.
15 minutes:
Oil temp 126 F.
20 minutes:
Oil temp 134 F.
25 minutes:
Oil temp 154 F.
30 minutes and pulling into garage:
Oil temp 167 F.
Questions remain:
-Is a fully warmed coolant taken to indicate a "fully warmed up" engine? Or is it rather a fully warmed oil? If one needs to wait until the engine oil is fully warmed before accelerating hard, then the only people who can do that are those who have greater than 45 minute commutes!
-At what point during the drive, has the engine warmed up enough to redline without undue wear? Past the 15 minute hump? Or must one wait forever, driving like a granny until almost on their own doorstep?
-What does this mean for short-trip commuters who can drive to work in 10 minutes or less?
Seems a lot of people just look at the dash temperature gauge, which is only reporting the coolant temperature, and then think it is ready to drive hard...
My coolant will spike above 200 F, but usually settles back to the 190's after I slow down. Engine oil does spike with hard throttle, and on a hot day and long drive I have seen it hit as high as 196 F, but on normal days it is 150-180 F.
With so much uncertainty, it is impossible to know whether to merge onto the freeway quickly or not, if it is just around the corner from your home or work...
But regardless I hope to have cleared up some of the theories in this thread.
From the drive home today, dry-sump oil system:
Outside temp: 59 F
Startup:
Coolant temperature increased immediately, reaching 100 F within the first minute. Oil temperature remained at 66 F and showed no increase.
5 minutes:
This is how long it took for the oil temperature to budge, increasing to 68 F. Meanwhile the coolant reached 145 F.
10 minutes:
Coolant reached stable operating temperature of 196 F.
Oil was only 74 F.
15 minutes:
Oil temp 126 F.
20 minutes:
Oil temp 134 F.
25 minutes:
Oil temp 154 F.
30 minutes and pulling into garage:
Oil temp 167 F.
Questions remain:
-Is a fully warmed coolant taken to indicate a "fully warmed up" engine? Or is it rather a fully warmed oil? If one needs to wait until the engine oil is fully warmed before accelerating hard, then the only people who can do that are those who have greater than 45 minute commutes!
-At what point during the drive, has the engine warmed up enough to redline without undue wear? Past the 15 minute hump? Or must one wait forever, driving like a granny until almost on their own doorstep?
-What does this mean for short-trip commuters who can drive to work in 10 minutes or less?
Seems a lot of people just look at the dash temperature gauge, which is only reporting the coolant temperature, and then think it is ready to drive hard...
My coolant will spike above 200 F, but usually settles back to the 190's after I slow down. Engine oil does spike with hard throttle, and on a hot day and long drive I have seen it hit as high as 196 F, but on normal days it is 150-180 F.
With so much uncertainty, it is impossible to know whether to merge onto the freeway quickly or not, if it is just around the corner from your home or work...
But regardless I hope to have cleared up some of the theories in this thread.
I dont know if there is a real good answer as to what minimum oil temp you should wait to before revving out an engine. I use both oil temp and oil pressure readings before I rev it up. I like to wait until my idle oil pressure is around 25psi and oil temp is 160+. My idle oil pressure will drop to 25 by the time the oil temp reachs 140ish. Normal oil temp at operating range is around 195 since I have an oil/coolant heat exchanger, and my coolant tstat is 195. I also have under piston oil squirters
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