Temp Sender for Early Cluster. (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Cruiser_Nerd

That 25 Guy.
Moderator
Joined
Dec 3, 2002
Threads
198
Messages
4,367
Location
Higganum.
Checked these values for Splangy, thought I'd post it up in a thread since I didn't see it in our old conversations. I believe this applies to all the early 25 and 40 clusters.

I did a few readings on a working stock sender so we could have a record of the values, unfortunately it wasn't too cool today (74*) but it doesn't matter much to the gauge.

So here's a picture of a stock sending unit on a 25.
IMG_0181.JPG



And here's the setup, to read the resistance you must disconnect the wire to the gauge. The yellow wire taped to the adapter pipe is a thermocouple to read the temperature.
74.JPG



OK, cold temp (gauge buried left) is 74*, resistance is 43 ohms. To read the resistance you must remove the wire to the gauge and read between the terminal and body of the sender.
74-43.JPG
 
Last edited:
102* and 24.9 ohms resistance:
102.JPG
102-25.JPG
 
Last edited:
151* and 24.4 ohms NOTE once you are in working range, there will be very little change in resistance................
151.JPG
151-244.JPG
 
Last edited:
164* and 24.3 ohms.............yes these are F not C degrees......
164.JPG
164-243.JPG
 
172* and 24.2 ohms..................this is where my thermostat opened.

172.JPG
172-242.JPG
 
And finally.................180* and 24.1 ohms and where the gauge should be sitting at that temp................
180.JPG
180-241.JPG
IMG_0201.JPG
 
For laughs I tried a temp sender that I had marked as 1970.........70* at 160 ohms and 200* at 65 ohms...............so with the old cluster it should basically go to cold on the gauge and stay there, which is what it did, and is why I've got this new temp sender on the shelf...........
 
Last edited:

Users who are viewing this thread

Back
Top Bottom