First step, pull the cover off the back, usually at the bottom and get ALL of the dust/dog hair/etc off the coils. Blow it off, vacuum it, whatever - start with that. My Samsung did that last year, fired up the compressor, blew all that shit off and back in the race.

defrost timer motor?
Clogged evap coil?

Defrost heating element stuck on ?

Plastic bag blocking vent under bottom drawer in freezer?

Damper stuck closed in freezer vent? (is that what was clunking?)

It could be a number of things but if its in your garage and its cold in there the cold can mess with the thermostat but normally that would cause the freezer to not stay cold enough and the fridge part would work fine. There is a $7 part to fix this

Is the evaporator fan motor running? Open the door and push the door switch closed with your hand.
Do you hear the fan motor inside running or feel any air movement?

My best guess in order of where I would start first, however your "clucking noise" has me perplexed sounds like a worn compressor. How cold is the freezer exactly in measurement of temp...? , cold is not an answer btw.

Damper Control Assembly
Thermistor
Evaporator Fan
Defrost Timer
defrost thermostat
Evaporator Coils

I have my 609 cert... I thought about getting my 608 III. I always liked working refrigeration.

faulty defrost timer motor will cause the evaporator to clog with ice since the automatic deforst does not work anymore. This prevents cold air from getting to the refrigerator section.

I’d go with the evap fan. I had similar issue. Clunks & screeching. Work then didn’t. Bearing on the old fan gummed & clogged. You may hear the fan running but at what speed? Replaced the evap fan and good as new. Easy fix just a bunch of screws in the bottom back panel.

Can you post the model # for the refrig?

If it is not a genuine part, you no longer have a UL rated appliance. If your house catches on fire and it can be traced to the fridge, your friendly insurance COmpaNy will do everything they can to not pay.

$15 for the Laser type from China Freight. Perfect for refrigeration system repairs. I use one treasure differential temps of the suction & discharge lines on refrigeration systems & A/C units.

Ok, so given that the problem is still freezer cold/refrig warm, it's typically 1 of 2 things, as has been covered plenty already: evaporator fan, and defrost system. You should hear the evap fan running most of the time the refrig is on, as long as it isn't in defrost mode. It *may* also be run through the freezer door switch so you might have to push the switch to get the fan to run if the freezer door is open. It's tricky to find schematics for Kenmore sometimes, is there any schematics tucked away perhaps behind the kick panel near the condenser coils? Might be on the right side once you get the kick panel out of the way. If evap fan is running, you'll need to remove the rear panel from the freezer. Usually 4-8 screws holding it on. If the coils are completely caked up in frost, you likely have a bad defrost thermostat and/or timer and/or heater (though it's often just the thermostat). It's also possible it's the damper you were looking at. Easy way to tell is if the damper door is open (as long as refrig section is warm, damper door should be open).

There's the evaporator fan in the freezer, and another fan behind/under the refrig next to the compressor (the condenser fan). If the evaporator fan is working ok, I'd pull the back wall out of the freezer and post a pic of the evaporator coils. Looking at how the frost is formed on the evaporator coils, we can try to determine if it's the defrost system, sealed system (freon, compressor, etc), or something else...

Looking at the back wall of the freezer, do you see a layer of frost on it?

So just to be sure, the freezer is freezing cold now, and the refrig section is warm/room temp?