I have gone through two A/C clutch coils.

The A/C has been working great. Then one day I smelled an electrical burning smell and the A/C started making a noise. I pressed the econo button and the noise and smell stopped. I replaced the clutch with one from my parts DII. About a month later that one did the same thing.

What should I look at for a cause?

 

unless they have changed, the gap on the clutch has to be "set" with a feeler gauge when installed. did you do that or just throw the clutch on? did you replace the clutch and coil?

 

I swapped out the complete clutch & coil assembly.

 

might want to do a gooole search adjusting A/C clutch air gap, all i can figure is the gap is to large and the coil had to work extra hard to lock the compressor in. Usually in that case the clutch will not engage resulting in no A/C.

that fact that hitting the econ button shut it down, kind of eliminates it being powered all the time

 

Found this:
Inadequate voltage to the coil will result in overheating of the internal winding and cause the clutch hub to slip against the face of the pulley. A compressor in the stages of failing due to slugging or loss of lubrication, or operating under a high pressure condition will cause the clutch to slip. The slipping occurs continuously during compressor operation and can subject both the clutch and coil to extreme temperatures up to 1,200 degrees F. This will quickly destroy the clutch and its internal components.

At the bottom of the page there is a failure summary chart which runs thru questions to find the cause: Examining Air Conditioning Clutch Failures in the Field

I need to run through the questions. I hope its the coil. A new coil is $34.

 

very nice find, it would make a good tech article