that motor & prop should be drawing a whole lot more than 6.86A add 40A. If your windings measure ok and you haven't lost any magnets out of your motor (it happens) it really does look like your esc is duff.
these turnigy dlux are good if a little bulky. worth getting the programme card as you can then access the data log. they are an odd shape so check to make sure it will fit
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