temperature gun to check temp gauge

[savage]

I want to check my mechanical temperature gauge, by using a temperature gun. What are the area's I should check on the engine, with the temperature gun? and what's a good temperature gun to use.

 

[badmuttstang]

I prefer a thermal coupler its more accurate and you can get them to hook up to most bolt meters. Inferred meters measure the air around the area as well so its more of an average. As for where to check if your trying to see if your gauge is working or accurate just prob right next to the sender weather it's electric or mechanical.

 

[nvrstuk]

x2 to the thermocoupler...

A Mustang guy that has done this comparison this year says that the infared gun is typically 10-13 deg F cooler than the actual temp read with a thermocoupler.... I just read his post, haven't actually talked to him about how he did the comparison...

 

[badmuttstang]

As a heating and air conditioning tech we don't use the guns unless we can t get anywhere near where we need to be and those temp numbers are really close just depends on quality of the gun but honestly a good one is still not accurate so why waste your money.

 

[badmuttstang]

By the way if you have a volt meter that can use a thermal coupler there only about $15 if you need the whole thing you can get a nice meter for less than $50 http://www.homedepot.com/p/Klein-Tools-Digital-Multimeter-MM200/202521267

 

[Broncobowsher]

As others stated, not the most accurate to use a gun. But it can tell you if you are close. Just shoot the thermostat area, that's really close to the temp sensor and has decent area to hit.

 

[bronconut73]

Most temp guns will be within 1 to 3 percent F.
It is true that they are also getting some air temp.
They are also getting some surface temp which is not the same as the coolant inside the engine....
But,
They are a great tool to have in your arsenal.
I use one at work everyday. It is a G.E. but my back up from Harbor Freight gives "very" similar results for 1/3 the price.

 

[RT9]

IR Guns are difficult to get accurate readings. They work on the principle of emisstivity - or a measuring of the wave length of the hot part. They are calibrated against a perfect, flat, black body. Therefore many things can affect the readings, like, shiny parts, color, round surfaces, etc.

I never believed my gauge on the bronco so I ran a magnetic thermocouple to the tstat housing back to the dash and plugged in my DVM. It was actually in close agreement.

 

[savage]

Hey badmusttang, I look at the volt meter, great price, only thing, do a I still need to buy the magnetic thermocouple, I couldn't tell if it came with the meter, and if not, where can I get one.

 

[badmuttstang]

Hey badmusttang, I look at the volt meter, great price, only thing, do a I still need to buy the magnetic thermocouple, I couldn't tell if it came with the meter, and if not, where can I get one.

It comes with the meter

 

[savage]

Great, I'll see if are homedepoy has one.

 

[JB Fab]

IR Guns are difficult to get accurate readings. They work on the principle of emisstivity - or a measuring of the wave length of the hot part. They are calibrated against a perfect, flat, black body. Therefore many things can affect the readings, like, shiny parts, color, round surfaces, etc.

Very true, if you plan to use one to, lets say double check your tranny or rear diff. you should paint a location with flat black paint, and hold the gun a right angle.

 

[DanHall]

Very true, if you plan to use one to, lets say double check your tranny or rear diff. you should paint a location with flat black paint, and hold the gun a right angle.

And get close to the location you are testing. Most have a measurement area that is is conical and gets larger the further you are away.

 

[RT9]

Here's my thermocouple. Works great.

At Gates we used the IR guns to monitor belts running on dynos. We did have issues to say the least.

 

[RT9]

I forgot to mention also the material will affect the reading. . Try and measure ir on steel or cast iron. Not aluminum.

 

[scotch]

The more accurate temp guns have adjustable emissivity so you can setup the gun for the type of material you are pointing it at, but they aren't cheap. I agree with the others, a wired probe hooked to a meter is your best bet. To improve your accuracy, try taping the probe tip to the block then tape a small piece of foam insulation on top of that. This will help prevent ambient air from being averaged into your measurement. Good luck.

 

[jw0747]

See the pic above. Point an infrared gun at either the blue painted manifold or the thermostat housing near the temp sender and it'll tell you what you need to know. I bought my infrared gun at Harbor Freight on sale for a good price. It's temp reading next to the sender is really close to what my dash gauge is showing.

 

[savage]

I forgot to mention also the material will affect the reading. . Try and measure ir on steel or cast iron. Not aluminum.

So I have a edlebrock intake, aluminum and the thermostat housing that is aluminum. So how will the thermocouple work and how would you hook it up to get a reading? Is my only choose a infrared gun.

 

[nvrstuk]

FYI... tape won't hold anything, it's too hot and the glue releases...

 

[RT9]

Good question. I imagine a bolt will work for the magnetic type. Then you can run a cable back into the cab and watch it when you're driving. Google Omega Engineering and I belive they sell bolts with thermocouples installed as well as hose clamps with T/Cs installed. The IRS gun will work, just the reading will be off. If memory serves me, shiny aluminum would read 100F but only be 90F. It's been a few years since I worked in the lab.