The motor coupler would usually only be the problem if both spin AND agitation failed. It would affect both.whirlpool washer won't spin so i change the motor coupling
... and spinning I assume?...but began to smell something burning and the washer completely stopped from washing or draining.
If so, all those functions are the responsibility of the main washer motor. The burning smell might be coming from it or even any electrical part (timer, wiring, etc.) in its circuit. Tracing the actual origin of the odor will likely be required to determine which.
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