[Dan O.]

Originally Posted by jeffpas

is there any way one can tell which is the problem?

A service technician would usually connect the compressor to a test cord directly, bypassing the relay and overload, to see if it would run and to also check its amperage draw. If all tested Ok, they might reinstall the devices and check the amperage draw at the time the overload tripped. If the amperage was Ok when the overload tripped, just the overload might be assumed to be defective and replaced. But when the symptoms point to either the relay or overload, often both are just replaced together.

If the compressor was found to be drawing excessive amperage, the compressor itself would be assumed to be the problem... as long as the power supply to the fridge was adequate.

I have heard that taking the starting relay out and shaking it, listening for a rattling sound, indicates it has gone bad.

That is a sure way to wreck even a good part. The type of relay used on your model has numerous moving internal parts. It will rattle... if you make it. That says absolutely nothing about its condition.

Violent shaking is not a test for any appliance part and should not be done, EVER!

I would assume if the compressor has broke, it would no longer heat up at all.

A compressor can be broke in any number of different ways. It doesn't necessarily have to be 'dead' as a doornail.

Surely there is some trick of the trade for determining which has failed.

No 'trick', just testing and deduction.

BTW. Your fridge model doesn't look to use any sort of capacitor so I wouldn't suggest you go on too long of a wild goose chase looking for one. A compressor 'hard start kit' (see the following link) might be able to be used if the cause of the starting problem is just the compressor starting to get 'tight' with age and use. They have to be wired in place though and it isn't always easy determining the correct terminals to put the wires onto, depending on the make of compressor in your fridge model. The kit will have directions for a couple of different wiring setups.

LINK > Refrigerator/Freezer Compressor 'Hard Start' Kit

JMO

Dan O.
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