Re: 12 old fridge: repair or replace
If you or he does the work, then it won't cost you any more than parts. I would recommend diagnosing the problem (probably a faulty thermocoupler ) and see what the parts cost and base your decision on that, if it's what I suspect, probably not more than $30.
The thermocoupler controls a door between the freezer and the refrigerator, when it faults, the door will usually stick in the open or closed position, sounds like yours is stuck open.
Look on-line for an owners manual or service manual for the refrigerator you're working on, at the very least it will have a parts view to know where to look. At best it will have a troubleshooting guide to help you narrow the problem down. You might also contact the manufacturer for help.
I suffer from CDO ... Its like OCD, but in alphabetical order, LIKE IT SHOULD BE!!!