WRF736SDAM Whirlpool Refrigerator

The short answer is to check with the manufacturer. That way you can be sure to stay within warranty guidelines.

The longer answer is that it varies from model to model. When a refrigerator is placed in a non-standard position (for example on its side), compressor oil can run out of the compressor and up refrigerant lines. So if you don't stand it upright and wait, the compressor will pump without sufficient oil -- not good.

-M

If it's "bubbling" while it's running it could indicate improper charge. A refrigerant system should have liquid at the metering device. If there is still vapour in the mixture(saturation temperature) then you are loosing capacity which would explain the long run times. It doesn't mean there is a leak it just means that it's not running at full capacity.

In this image the metering device is an expansion valve. www.wikipedia.com

It gets pretty complicated but to aid you in your search for the problem if something you try makes the bubbling sound go away you may be on the right track. Keep in mind any changes to system take about 15 minutes to stabilize. Sometimes just pulling the fridge away from the wall does the trick. With fridge has bubbling often indicates too much heat overall in the system.