Not cooling, but fan running, light working and clicking

My fridge and freezer are not cooling. The light inside the fridge works and the fan is running. Cool(ish) air is coming in through the freezer (it is a bottom freezer unit). Every few seconds, I hear a clicking noise. I shook the fridge (in frustration!!) and for about 20 hours, it started working again, but now is back to not cooling- the ice that froze during that time period has now melted again.

If it is the relay, I would pay someone to fix it or try myself. If it is the compressor, I think it is time for a new unit. The problem is that every service wants to charge $75-100 just to come look at it.

Suggestions???

Hi.

Pull out the fridge, get to the compressor, remove the old relay overload and shake it. If that rattles - get a new start components 12555902

Here are the breakdown diagrams and http://www.appliancepartspros.com/partsearch/model.aspx?model_id=23141

Thank you . Post the results.

Simon.