Temperature display and overheat alarm installation

[Hubert_25-25]

I am not a fan of temperature elements sitting on top of radiators as my only means of engine monitoring for many reasons.  Much preferred is a temperature pick up on the cylinder head.  I also prefer to not have an instrument out on the end of the hood that I cannot see at night.  What I have installed is a temperature display that also has an adjustable audible alarm.  I installed it on a bracket that allows the display to be folded up under the dash when showing the car.  The display and sensor is $46.  If display in degrees C is preferred, it is a little cheaper. 

https://www.ebay.com/itm/FAHRENHEIT-TEMPERATURE-CONTROLLER-OVERHEATING-ALARM-ENGINE-WATCHDOG-CAR-BOAT/121932374196?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

 

You could use an existing bolt on the cylinder head.  The sensor has a ¼” hole in it for mounting.  I chose to install mine inside the spark plug cover on my 1925 Buick so that my engine looks entirely stock.  I could also just as easily have installed it on the back of the cylinder head.  I cleaned a spot on the cylinder head with lacquer thinner and then used JB weld to attach a ¼” nut.  The head should see less than 210F if all is function satisfactorily.  Once cured, I attached the sensor end with a short ¼” bolt and star washer.  The sensor is the copper item shown between the spark plugs.

My car is also 6 volts.  I installed a 6 volt to 12 volt “step up” transformer.  About $15.

https://www.amazon.com/gp/product/B01L90B3RI/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1

This photo shows the mounting bracket that I made.  The design allows the display to be pushed under the dash so that I do not need to remove it when the car is being shown.  Your attachment of the main bracket will be slightly different than mine for other vehicles.  The 2 smaller brackets that hold the display and allow it to rotate would be the same.  While I was doing this, I also added a 12 volt cigarette lighter plug so that I can charge my cell phone if needed too. 

 

These are the templates that I made first.  Then I made the parts from .030 sheet aluminum.  Easy to cut with tin snips. I used six #10 x ½” machine screws and nylock nuts.  

I wired this to the ignition switch so it is only on if the motor is on.  A 3 amp fuse should be used to protect this circuit. 

Instructions explain how to set the high temperature alarm, but they do not do a great job.  To change the set point, press “set”, Use the up arrow to raise the set point. Press “set” again to hold the number.     

Hugh

Edited July 26, 2019 by Hubert_25-25 (see edit history)

[27donb]

Nice setup!  Please share some temp readings too. 

[Hubert_25-25]

Don,   

         Today I drove my 1925 Buick 26 miles.  At 40 MPH my engine temperature is around 195 F.   On slower drives around town, the temperature is around 180F.  The response time is really good.  If you drive it at speed and then park the car, you will see the temperature rise  about 20 degrees.  Once you then restart the car you can see the cooling system doing it's job and bringing the temperature back in line.   I have only had it installed for a couple of days, so I will repost after I drive it a little more.   Hugh

[DB26]

Very cool. Might do something similar. 

[27donb]

On 7/26/2019 at 8:30 PM, Hubert_25-25 said:

Don,   

         Today I drove my 1925 Buick 26 miles.  At 40 MPH my engine temperature is around 195 F.   On slower drives around town, the temperature is around 180F.  The response time is really good.  If you drive it at speed and then park the car, you will see the temperature rise  about 20 degrees.  Once you then restart the car you can see the cooling system doing it's job and bringing the temperature back in line.   I have only had it installed for a couple of days, so I will repost after I drive it a little more.   Hugh

 

What does the motometer in the radiator cap read, in relation to the digital readings?  I know the motometer doesn't have numbers or graduations, but is the thermometer at half gauge at 180 degrees, for example? 

[DB26]

I just bought the 6 to 12 volt converter that you linked to. This should be fun. 

[Hubert_25-25]

The 6 to 12 volt converters are interesting.  The one that I posted above is rather robust and has a heat sink.  It is rated for 3 amps.  They also have a 10 amp version that is around $30.  I have also seen some really small ones that look like an inline fuse.