MTFCA Forum

I have a friend that is looking to buy a 31 Model A but he needs to know if its running at the right temperature, Can I take the moto meter off my Model t radiator cap and put it on the Model A radiator cap and will it be the same as a Model A moto meter? If not I do have thermal scanner I can point down into the radiator and scan the temperature. What is the normal temperature that Model A runs at? Thank you.

moto meter doesn't care just reads water temp

The motor meter sensor isn't long enough to reach the water. It actually reads the air temperature in the tank.
Very inaccurate actually. It's kind of like a T ammeter, What you see is for reference.
If you want accuracy, you put a sensor in the water outlet.

You can get a cheap digital baking probe on amazon and dip it down into the coolant. Some digital multimeters have a thermocouple function. A wire thermocouple is inexpensive and plugs into the meter. The end can be put way down into the radiator or better screwed down onto the block.

Will wrote: ↑

Thu Nov 14, 2024 6:23 pm

I have a friend that is looking to buy a 31 Model A but he needs to know if its running at the right temperature, If not I do have thermal scanner I can point down into the radiator and scan the temperature. What is the normal temperature that Model A runs at? Thank you.

Yes, use the thermal scanner to check operating temp. The engine coolant should run around 180 degrees, normal temps for combustion gas engine.

I like to point at the radiator top tank metal , record, and then point at lower pipe for return coolant temp, should be 40 or more degrees difference indicating a good cooling system

Here is a video on such testing on a Model A

https://youtu.be/n92soRoeTis?si=Zlq2I6kfVZTPNU08

Will wrote: ↑

Thu Nov 14, 2024 6:23 pm

I have a friend that is looking to buy a 31 Model A but he needs to know if its running at the right temperature, Can I take the moto meter off my Model t radiator cap and put it on the Model A radiator cap and will it be the same as a Model A moto meter? If not I do have thermal scanner I can point down into the radiator and scan the temperature. What is the normal temperature that Model A runs at? Thank you.

No & maybe!
A Model T radiator cap screws on and has the threads on the outside of the cap. A 1930-31 Model A radiator cap is a twist on type
A Moto-Meter is designed to measures water vapor temperature. An A cap's Inner diameter of bottom opening: is 2.44" & the T cap radiator cap has as 2" outside diameter. The system is not pressurized so some method to hold the cap in position may be necessary. Having said all this, Moto-Meter accuracy can be questioned - age etc.

As suggested best to get a thermal sensor HF has one for $29

I’ve used a remote baking or grilling thermometer, wireless. Use a proper diameter rubber test cork with the hole in the center. Stick the measure probe in the hole down to the proper depth. Assuming this is just for measuring purposes and notperminent, use duct tape to secure the probe in the cork. Use remote monitoring reader or cell phone to see the temperatures. Done it several times! Works well. Try not to get caught using your wife’s probe!

If it do not boil - it is not running hot. Make sure ignition are advanced properly and the fuel mixture is optimal.