Full synthetic making the motor heat up slower?

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I've got about 500 miles since I changed the oil in my Accord. I'm one to let the engine idle for 2 to 5 minuites on a cold start. If the engine is warm then I don't bother. What I have noticed is the engine takes a little bit longer for the temp gauge to move since installed the synthetic oil. Has anyone experienced this when they switched to synthetic? I'm not looking to get flamed for idiling my car, I've been doing it for years and it allows me to make sure I have everything before I leave my driveway(phone, coffee, etc.) Thanks in advance, Steve.
 
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Synthetic oil does reduce friction in an engine, but the combustion process is where engine heat comes from and is controlled by the engine cooling system.
 
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Yeah but the engine will warm up quicker with a light load. The heavier oil puts a load on the engine. The FI might react by increasing the fuel injected. This is why I start the car rolling down the street with the engine just idling as soon as I can. Then I get it out on the next street, which is 30 mph, and I can get it up to that speed with hardly any gas pedal. Cruising on that street will warm up the engine much quicker. The quicker the engine gets warm the less wear.
 
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Originally Posted By: tig1
Synthetic oil does reduce friction in an engine, but the combustion process is where engine heat comes from and is controlled by the engine cooling system.
Hey tig. It may seem like I'm picking on you the past couple days but I assure you I'm not,however I am taking issue with a few points in your posts and this one in general I'd like to disagree with. Synthetic oil is oil,just a more pure form so I disagree that synthetic oil reduces friction vs a conventional oil The additive package,namely the friction modifiers are what reduce friction primarily so I contend that whether conventional or synthetic if the additive packages are the same then both lubricants will reduce the co-efficient of friction equally. Maybe in the 70s your statement was true however today's conventionals have closed the gap significantly so I don't feel your statement is correct. But please prove me wrong. I'll happily admit I'm wrong if you can find something that says so. And I don't mean marketing fluff off of mobils website. Show me actual data referring to 2 oils with comparable additive packages with the difference being one is synthetic. Op Synthetic oils don't reduce friction any different than conventionals do. They resist oxidization better,resist thermal breakdown better etc which equals them lasting longer in service. That is their benefit over their conventional counterparts. In fact because conventional oils are polar there is a case to be made that conventional lubricants may reduce wear over their synthetic brethren,as long as the interval isn't too long. And synthetic oil has little to do with how fast your engine warms up. The temp gauge is only showing coolant temp. It's posdible that synthetic oil does reduce more friction than conventional however if it does its minimal at best. And no spanking please tig. I'm still having a problem sitting down from last time.
 

Droopy

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My factory fill was a blend and with about the same temps outside it would warmer faster. This is what I'm basing my post off of. I know the coolant gauge measures coolant temp but it does measure the temp in the engine to some extent IMHO.
 
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Originally Posted By: datech
Yeah but the engine will warm up quicker with a light load. The heavier oil puts a load on the engine. The FI might react by increasing the fuel injected. This is why I start the car rolling down the street with the engine just idling as soon as I can. Then I get it out on the next street, which is 30 mph, and I can get it up to that speed with hardly any gas pedal. Cruising on that street will warm up the engine much quicker. The quicker the engine gets warm the less wear.
"The quicker the engine gets warm the less wear" I've gotta disagree here. For example I can get my engine hot in seconds by holding the rpm at 5000 from cold. Is that going to create less wear than letting the engine idle til up to operating temp? In fact a slow warm up with no load on the engine would create the least amount of wear. Way less thermal shock to the metal,the different metallurgy of all the moving parts is allowed to expand at a slow steady rate which is way better than the alternative. We get seriously cold here in saskatchewan. when I start my vehicle I let it warm up enough to blow warmish air from the vents so I can keep the window from fogging up inside. If it's not that cold,let's say -20c I don't bother with a warm up however I am easy on the rpm and don't exceed 2000 or so until the engine is warm. I've also acquired 2 trucks from my dad that he bought new. Both if them were dodges. One was an 89 the next was a 96. Both had a 318 under the hoods. Those trucks routinely idled for a half hour every morning in the winter,and easily idled half the working day away then in the evenings there was hockey for one of us which he chauffeured us to. Both those trucks were running mint at 450k when the 89 needed more work than the truck was worth and I totalled the 96. So I contend that in my experience wear is reduced vs start and go during the winter months. Oil doesn't lubricate well in sub freezing temps,especially when temps are below -30c,and the oils additive package isn't activated until the oil gets hot. Not to mention the metals the engine is made from going from extreme cold to operating temp which is a swing of easily 140c. Considering today's engines use of different metals like aluminum heads on a cast iron block which translates to different rates of expansion it's amazing engines last as long as they do all things considered. During the warmer months it's not as big of a swing and the oil itself heats to operating temp faster which translates to less wear too. So that's my position. Slow warm up wears an engine less than a quicker one. Yes the oil warms up slower and therefore the additive package takes longer to achieve full effect however because there is little to no load on the engine wear is minimal. Even a light load on a cold engine means the rings are putting more pressure in the bore and because the oil is cold little to no oil is able to splash up there. The oil when cold has a harder time lubricating the cams on a sohc/dohc engine because they require the oil to mist which cold oil just can't do,so wear is accelerated and friction increased until the oil gets hot enough to spray up top. I invite anyone to show me I'm wrong. Teach me something,show me what I've missed or the flaws in my thought process. Thanks
 
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Originally Posted By: Clevy
Originally Posted By: tig1
Synthetic oil does reduce friction in an engine, but the combustion process is where engine heat comes from and is controlled by the engine cooling system.
Hey tig. It may seem like I'm picking on you the past couple days but I assure you I'm not,however I am taking issue with a few points in your posts and this one in general I'd like to disagree with. Synthetic oil is oil,just a more pure form so I disagree that synthetic oil reduces friction vs a conventional oil The additive package,namely the friction modifiers are what reduce friction primarily so I contend that whether conventional or synthetic if the additive packages are the same then both lubricants will reduce the co-efficient of friction equally. Maybe in the 70s your statement was true however today's conventionals have closed the gap significantly so I don't feel your statement is correct. But please prove me wrong. I'll happily admit I'm wrong if you can find something that says so. And I don't mean marketing fluff off of mobils website. Show me actual data referring to 2 oils with comparable additive packages with the difference being one is synthetic. Op Synthetic oils don't reduce friction any different than conventionals do. They resist oxidization better,resist thermal breakdown better etc which equals them lasting longer in service. That is their benefit over their conventional counterparts. In fact because conventional oils are polar there is a case to be made that conventional lubricants may reduce wear over their synthetic brethren,as long as the interval isn't too long. And synthetic oil has little to do with how fast your engine warms up. The temp gauge is only showing coolant temp. It's posdible that synthetic oil does reduce more friction than conventional however if it does its minimal at best. And no spanking please tig. I'm still having a problem sitting down from last time.
Here is something from Shell on synthetic oil and reduced friction.
 
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I also just did my first oil change on a mid-90s Lexus SC. I changed it from whatever the GMC dealership I bought it from uses for their full synthetic and used a semi-syn in MC 5w-30. I thought it warmed up slower then the MC 5w-20 I used in the 06 Accord V6. I decided to use the 30 weight MC cause this engine is a 1995 versus 2006 that was the Honda and being a 11 year older engine with less tech(VVT or VTEC in Hondas case), I thought I better stick to the original recommendation rather then the back-specd, CAFE induced 20 weight. I might use the 20 weight for one OCI in my next OCI just for comparison but I just wanted to chime in because I also noticed a slightly longer time for the coolant temps to warm up and I too was concerned. Looks like as long as I keep a low load and take it easy on the RPM throttle, I should be good until it warms up. Now that I have answered the cold temp protection, I wonder if my viscosity is too thick for warmed-up or hot temps. I just checked in after not doing so for weeks and I click this thread and Clevy is on Fire.. Most informative posts since I've been here since 2006. I vote this thread be stickied because it is so choke-full of good and accurate info by Clevy. Good job, son!
 
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Originally Posted By: Droopy
I've got about 500 miles since I changed the oil in my Accord. I'm one to let the engine idle for 2 to 5 minuites on a cold start. If the engine is warm then I don't bother. What I have noticed is the engine takes a little bit longer for the temp gauge to move since installed the synthetic oil. Has anyone experienced this when they switched to synthetic? I'm not looking to get flamed for idiling my car, I've been doing it for years and it allows me to make sure I have everything before I leave my driveway(phone, coffee, etc.) Thanks in advance, Steve.
IME with modern cars it seems a long warm up period is not necessary, but I have also never seen any indication that it harmed anything either. There is very little wear while idling, but there is also very little heat generated. Since there are so many variables like cooling system volume, thermostat, fan type, displacement, tuning, ambient temp, etc., that all affect warm up it would seem that broad statements are likely wrong for some cars. In our mild climate we strive to ease out almost immediately but just drive gently until the engine warms a bit. It is important to note that you are warming up transmission and other wearing parts, too ..
 
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Originally Posted By: tig1
Synthetic oil does reduce friction in an engine, but the combustion process is where engine heat comes from and is controlled by the engine cooling system.
Nope, put an engine on a test bench, driven by an electric motor, and the lubrication system will get nearly as hot without fuel and fire as it does with... Don't believe me ? Try running a shop compressor.
 

NO2

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The energy that heats a compressor body is a result of friction and (mostly) the rise in temperature from compressing the air or other gas. You have that plus the energy loss (80%+) of imperfect conversion from chemical to kinetic energy in an IC engine. Compressor oils rarely exceed 100C, and many are designed to be permanently lubricated (e.g. refrigerators). Similar oil temperatures are a result of the more efficient cooling system of an IC engine. It would be pretty difficult to measure a say, 0.5%-1% decrease in friction without laboratory conditions and instruments.
 
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Originally Posted By: Shannow
Originally Posted By: tig1
Synthetic oil does reduce friction in an engine, but the combustion process is where engine heat comes from and is controlled by the engine cooling system.
Nope, put an engine on a test bench, driven by an electric motor, and the lubrication system will get nearly as hot without fuel and fire as it does with... Don't believe me ? Try running a shop compressor.
Is it fair to say this depends on the application? I see your point, but what sort of RPMs does a shop compressor see vs. a car engine? (Honestly I have no idea..) I would think a faster RPM regardless of electric or combustion propulsion would create more friction (heat). No doubt they produce some heat though.. look at the heat fins they need to have on them. Look at 2 stroke LB engines! A more fair comparison IMO would be an electric motor and gas engine similar in HP running at the same RPM under the same load.
 
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I hate to be a dick, but I think the premise of the original post is highly theoretical and speculative at best. I don't see synthetic vs. dino oil as playing any role in allowing engines to warm up faster.
 
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Seriously? Compressing air takes a lot of energy, it's not from the frictional losses. That would be like running the engine (via a motor) with the spark plugs installed. No doubt that would consume quite a few HP that are going to have to be rejected as heat.
Originally Posted By: Shannow
Originally Posted By: tig1
Synthetic oil does reduce friction in an engine, but the combustion process is where engine heat comes from and is controlled by the engine cooling system.
Nope, put an engine on a test bench, driven by an electric motor, and the lubrication system will get nearly as hot without fuel and fire as it does with... Don't believe me ? Try running a shop compressor.
 
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Originally Posted By: kschachn
Seriously? Compressing air takes a lot of energy, it's not from the frictional losses. That would be like running the engine (via a motor) with the spark plugs installed. No doubt that would consume quite a few HP that are going to have to be rejected as heat.
OK, the heat in the oil of a compressor is made by the coal burning at the power station, tig1 was right, no fuel no POWER, and therefore no heat...the heat of combustion isn't what drives (say) temperature rise across a bearing.
 
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I would then have to say the friction of the oil heats the oil. The thicker the oil the faster it heats up. The thinner oil would take longer to heat up. Proving the findings of the topic.
 
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used_oil, to demonstrate your point, here's some stuff that I did to demonstrate the effect in another thread. My Briggs (mower) I ran 5W20 over winter, and as I was changeing it out (was going back to SAE30), I decided to throw some 20W60 (thickest I could get within the town on a weekend, to bookend my experiment). After mowing, at 4C 10 mins on the Governor and the 5W20 was 87C (thermocouple down the dipstick)...replaced with 20W60, and 10 minutes on the Governor had it at 97C. Simply a new equilibrium point, where the increased work that is done against the oil needs to be dissipated...same environmental heat sink means the oil temp goes up.
 
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