Use an infrared pyrometer to measure engine temp?

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I've always wondered what might be an effective way to measure when my motor reaches its "normal" temperature. Theoretically, if I knew this, it might make a difference in the oil that I choose to use in my vehicle, right? Does it take 15 minutes, 30 minutes, etc.?

I have a Toyota Tacoma with the 2.4 motor which is an iron block, but aluminum cylinder head and aluminum valve cover. If I want to try using an infrared pyrometer ( https://duckduckgo.com/?q=infrared+pyrometer&t=ffsb&ia=products ) to gauge when my truck reaches it's normal temperature, what part(s) do you think I should "aim" at to take a temperature reading from?

Thank you,
Ed
 
Originally Posted By: Chris142
They wont measure aluminum or shiny parts.


Don't quote me on this but I think if you put some black flat engine paint on a shiny surface, you can then accuratly read that surface temperature (this is due to the emissivity of the surface and the IR device needing it to be close to 0.95).

IR Emissivity
 
better off with oil or coolant temp.

Those IR thermometers are good for checking wheel bearings on trailers..
and brake function(sticking brakes etc)
 
Originally Posted By: Ed_Flecko
I've always wondered what might be an effective way to measure when my motor reaches its "normal" temperature.


Even though different emissivities will affect the accuracy of your reading, this doesn't seem to matter much, since you say you're interested in timing, not the absolute temperature.

In that case what you want is the temperature curve of whatever you're pointing at. When it flattens off, you're there.

Unless you only measure with the car stationary, though, you'll have an observer effect problem, in that you'll probably have to stop to take a measurement and that'll affect the result.

Originally Posted By: Ed_Flecko

Theoretically, if I knew this, it might make a difference in the oil that I choose to use in my vehicle, right?


Dunno. What's your rationale? How would heat-up time influence your oil choice, and why?
 
Originally Posted By: Chris142
They wont measure aluminum or shiny parts.


Yes, they will. My Fluke IR thermometer will read the temperature from -30 to 500 C (932F) https://www.amazon.com/Fluke-62-Infrared-Thermometer-Series/dp/B00U4EP04I on dull or shiny aluminum, chrome, black plastic, ceramic coated stainless steel, meat on the barbeque grill or in the oven, the cooking element on the stove, inside my mouth or the palm of my hand, any color of painted surface I can find, etc...It is a very useful tool; to answer the OP's question, I would say unfortunately, you can't shoot that IR beam into your crankcase or cylinder heads in operation...

My thermostat is 180 and common sense in mild weather tells me that the engine is at equilibrium temperature within 10 minutes of the coolant stabilizing temperature wise; although I really don't know what this would have to do with oil selection in Sacramento CA. If I had to guess, I would agree with a previous poster that my engine is completely warm internally when both my intake and exhaust manifolds don't get any hotter; my stainless exhaust manifold usually stabilizes about 470-500 F.

I usually hang out in bypass filters; here are some pics of my engine compartment and you can see my ceramic coated stainless exhaust manifold: https://bobistheoilguy.com/forums/ubbthreads.php/topics/4223331/Re:_centrifuge#Post4223331
 
Originally Posted By: Ihatetochangeoil
Originally Posted By: Chris142
They wont measure aluminum or shiny parts.


Yes, they will. My Fluke IR thermometer will read the temperature from -30 to 500 C (932F) https://www.amazon.com/Fluke-62-Infrared-Thermometer-Series/dp/B00U4EP04I on dull or shiny aluminum, chrome, black plastic, ceramic coated stainless steel, meat on the barbeque grill or in the oven, the cooking element on the stove, inside my mouth or the palm of my hand, any color of painted surface I can find, etc...It is a very useful tool; to answer the OP's question, I would say unfortunately, you can't shoot that IR beam into your crankcase or cylinder heads in operation...

My thermostat is 180 and common sense in mild weather tells me that the engine is at equilibrium temperature within 10 minutes of the coolant stabilizing temperature wise; although I really don't know what this would have to do with oil selection in Sacramento CA. If I had to guess, I would agree with a previous poster that my engine is completely warm internally when both my intake and exhaust manifolds don't get any hotter; my stainless exhaust manifold usually stabilizes about 470-500 F.

I usually hang out in bypass filters; here are some pics of my engine compartment and you can see my ceramic coated stainless exhaust manifold: https://bobistheoilguy.com/forums/ubbthreads.php/topics/4223331/Re:_centrifuge#Post4223331


Oh they'll give you a reading, whether it's accurate or not is a different story.
 
Don't know about using IR to get what your looking for, but if your after the oil then I might IR the oil pan.

The only time I use the IR on an engine was on the Harley checking the temp at the head right next to the exhaust pipes and also at the spark plugs. Something didn't seem right and found one of the plugs was not firing right (seems weird on a potato sound Harley), then my hand at the exhaust outlet one was cold compared to the other. Changed plugs and all was well.
 
Originally Posted By: Errtt
Don't know about using IR to get what your looking for, but if your after the oil then I might IR the oil pan.


I'm thinking that would work the best to determine what temperature is the maximum that my oil reaches and will give me an idea of how long the motor has to be running before it reaches that maximum.

smile.gif


Ed
 
Originally Posted By: JetStar
Originally Posted By: Ihatetochangeoil
Originally Posted By: Chris142
They wont measure aluminum or shiny parts.


Yes, they will. My Fluke IR thermometer will read the temperature from -30 to 500 C (932F) https://www.amazon.com/Fluke-62-Infrared-Thermometer-Series/dp/B00U4EP04I on dull or shiny aluminum, chrome, black plastic, ceramic coated stainless steel, meat on the barbeque grill or in the oven, the cooking element on the stove, inside my mouth or the palm of my hand, any color of painted surface I can find, etc...It is a very useful tool; to answer the OP's question, I would say unfortunately, you can't shoot that IR beam into your crankcase or cylinder heads in operation...

My thermostat is 180 and common sense in mild weather tells me that the engine is at equilibrium temperature within 10 minutes of the coolant stabilizing temperature wise; although I really don't know what this would have to do with oil selection in Sacramento CA. If I had to guess, I would agree with a previous poster that my engine is completely warm internally when both my intake and exhaust manifolds don't get any hotter; my stainless exhaust manifold usually stabilizes about 470-500 F.

I usually hang out in bypass filters; here are some pics of my engine compartment and you can see my ceramic coated stainless exhaust manifold: https://bobistheoilguy.com/forums/ubbthreads.php/topics/4223331/Re:_centrifuge#Post4223331


Oh they'll give you a reading, whether it's accurate or not is a different story.


OK; you're dead wrong...What can I do to convince you? Or is your mind made up regardless of what I post? Have you heard of temperature indicating sticks used in the welding industry?
 
I have a raytek IR gun

At full engine temperature:
when pressed to the top tank of my aluminum radiator, it will read 107.5f
when pressed to the top tank with a piece of white gaffers tap on it: 136.5
When pressed to black gaffers tape on top tank: 197.5 F.

Respect for Fluke, but I am unaware of how it could read the exact same accurately, precisely on each one of these different surface colors

As far as when my engine is at full temperature, the coolant temp gauge maxes out long before my mechanical oil pressure gauge indicates the oil is as hot as it gets as the same engine rpm. And my coolant temp is an older gauge before they Dummified them so as to not freak out the modern consumer who might freak out with a needle that swings 1/16 an inch up and down when going up or downhill.
 
Originally Posted By: Ihatetochangeoil
OK; you're dead wrong...What can I do to convince you? Or is your mind made up regardless of what I post? Have you heard of temperature indicating sticks used in the welding industry?


They are IR ?

Or your IR gun is made up of them ?

Or they are irrelevent to the thread ?

The question of accuracy is determined by the emissivity of the surface, and you getting that right before you take a temperature reading...general stuff, fine...precision stuff you need to get it right...shiney Al us different, and will under-read if you don't have the right emissivity.

To the OP, dropping a type K thermocouple down my dipstick and into the area where the hot oil is dropping back from the rotating/reciprocating stuff, versus shooting the pan is about 10-15C...18-25F lower at the pan with the gun.
 
Originally Posted By: Shannow
Originally Posted By: Ihatetochangeoil
OK; you're dead wrong...What can I do to convince you? Or is your mind made up regardless of what I post? Have you heard of temperature indicating sticks used in the welding industry?


They are IR ?

Or your IR gun is made up of them ?

Or they are irrelevent to the thread ?

The question of accuracy is determined by the emissivity of the surface, and you getting that right before you take a temperature reading...general stuff, fine...precision stuff you need to get it right...shiney Al us different, and will under-read if you don't have the right emissivity.

To the OP, dropping a type K thermocouple down my dipstick and into the area where the hot oil is dropping back from the rotating/reciprocating stuff, versus shooting the pan is about 10-15C...18-25F lower at the pan with the gun.



I referenced temperature indicating sticks (tempilstix) because they are manufactured by the same company that makes (some) IR noncontact thermometers: http://www.tempil.com/temperature-indicators/ perhaps they are a little off topic to this thread.

Those who question the accuracy of IR thermometers need to either quit shopping at Lowe's for industrial equipment or explain how and why IR thermometers are available with certification to NIST: http://www.tempil.com/temperature-indica...ed-thermometer/

Shannow, I have a high degree of respect for your input; and I don't know how "shiny" the shiny aluminum is that you are questioning, but I have (aftermrket) polished aluminum filter housings and other aluminum pieces, stainless, and chrome under the hood of my car whose temperature I can measure with both tempilstix and IR and obtain similar results.

To the OP: I have not done it, but I totally agree with Shannow that a thermocouple dropped (lowered) down the dipstick tube will read slightly higher than your oil pan.
 
My car spent the night in a 65 degree (approximately) garage. Here are pictures of IR temperatures on chrome plated aluminum, polished aluminum, black plastic, grey plastic, chrome plated brass, ceramic coated stainless steel, etc. Anyone can let me know which picture(s) you believe have inaccurate readings on the IR:








I have an electrical engineer, some very knowledgeable people, a video and a manufacturer's instruction manual telling how wrong I am, meanwhile, I am LOOKING at accurate results in front of my eyes. Sorry guys, I believe my eyes. In the near future, I can set up my own hot plate (with a calibration sticker) and do my own experiments with different materials and temperatures.

Apologies to the OP; this is off topic, but I do not appreciate having my credibility questioned.
 
Whatever you use the surface temp will be below the actual temp of coolant or oil. No OBDII port to hook up a scanner to see the temp?
 
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