T-23f true freezer compressor makes rattling noise then starts sometimes i believe it is the over temp compressor relay

SOURCE: True Freezer Running Too Cold

thermostat is stuck closed, if not compressor relay is stuck closed, if not then the defrost timer is stuck closed. test the components in that order.

SOURCE: convert freezer to refrigerator

Converting a freezer to run like a fridg can be done ,however it is sometimes tricky. you have to replace the thermostat, you will also want to shorten the defrost time setting. and may have to disable the fan delay to let the evaporator fans run all of the time, to prevent short cycling of the compressor.

SOURCE: How To Replace Relay On True T-72 Reachin

If it's mounted inside a box along with the capacitors there is 1 screw holding it from the back. Often you have to unmount the box from the compressor to access the screw.