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Best places to get fluid temperatures?

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Since I recently graduated with a degree in computer hardware engineering tech. from Oregon Tech, I was thinking about making a small system to monitor different temperatures including coolant, oil, air intake, cat temp, etc.

 

My question is, where would be the best place to mount my sensors? I can get different sensors depending on the best place.

 

For coolant, I found the following from a post from Skip, so I could most likely just take a tap off of one those sensors.

 

The readings should be as follows

H20 Temp (deg F)_______Res. (ohms)

14____________________7-11.5 k ohms

68____________________2-3 k ohms

122___________________700 - 1000 ohms

 

 

I'm just not sure on getting oil temp. I've read posts where people say what they're temps are before/after adding an oil cooler, I just want to know how they got the temps :-)

 

I also hope to use this system to control one or both of the electric fans (I just took off the motor driven one). I also have a dual core rad I may swap in sometime I get the time.

 

Thanks

-Dave

Well I can't help you out too much on this one but I just want to say, Congratulations fellow OIT alum. Go Hustlin' Owls

 

 

Dave,

Congrats on your degree, well done sir.

 

The post you show from me was for testing the fuel injection thermo sensor

The chart shows resistance reading vs temp for the sensor.

 

I have 2 fluid and 2 air temp monitors mounted in my turbo wagon.

 

I have placed my thermocouples in

 

a) the air cleaner element

 

B) the throttle body bore, just above the throttle plate

 

c) the water jacket (upper goose neck fitting - just before the radiator but after the thermostat)

 

d) in the oil pan approx. 2" past the bottom of the dip stick.

Note: this is an intercooled turbo engine with some modifications.

 

Your exhaust temp should be before your first cat. The cat will be combusting unburned hydro carbons and the exhaust temp afterward will not be a true combustion chamber temp representation.

 

 

 

Hope this gives you some ideas.

Coolant temp I would measure right at the thermostat; and prolly right before it. That's going to be where the hotest coolant is spitting out of the engine and into the radiator for cooling off.

  • Author

Skip, can I ask how you got your sensor into the oil pan? (You can't tease like that without giving any details :D ). I was thinking of drilling and tapping a hole in the side of it to mount a normal coolant temp sensor.

 

Only problem with that... I'm not sure how thick the metal is on the oil pan, and if it failed, well, dead engine comes to mind...

 

I'm also contemplating taking a coolant sensor, sticking it in a pan with water, and just recording the temp/resistance as it warms up.

 

 

thanks for the ideas

Hoozie,

I am a charter member of the KISS Club.

 

I ran the thermocouple wire down the dip stick tube.

My TC wire is 22 AWG so the rubber grommet on

the dip stick holds it in place just ducky.

 

The TC for the coolant, runs under the upper rad hose,

does a "U" turn and sits almost on top of the t-stat.

 

The one for the throttle body (intake air temp)

runs under the rubber boot connecting the intake

plenum to the TB.

The TC wire is expoxied to the wall of the TB.

The junction is in the air flow.

 

My air cleaner is now mounted inside the inner fender,

the TC goes through the hole I cut for the duct and simply

wedges in the folds of the element.

 

Hope this helps and good luck

with the project.

 

BTW

I use a Fluke rack mount lab digital, using type "J" TCs, with a TC selector switch.

It needs 120 Vac so I have a cheap (150 W) inverter mounted in the glove box..

Take a peek if you want

 

Fluke an such mount Picture

  • Author

awesome, thanks a lot,

 

I haven't used those kinds of thermocouples much

 

\me runs off to do some research :-)

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