After 110 hrs of flawless operation my 114 series pmag heat indicator turned gray. I noticed after a refueling on a 80 f day when I removed the top cowl to troubleshoot the unit after it would not work. I did not realize at the time that heat soaking on the ground could cause the unit to not work. So I reworked what appeared to be a faulty ground wire which took about 45 mins. fired up; the pmag was working and flew 1/2 hr to base. Thinking the ground was the culprit.
But when I got home curiosity got the better of me and when I tried to restart the hot engine after 10 mins or so the pmag would not work. So now I figure it's the heat and sure enough this evening after flying a 1/2 hr. In 58 degree temp I let it sit w/ the oil door open fired it up and at first the pmag was not working as evidenced by 0 rpm's on the tach, but after about 20 seconds of air being pushed down my 1" dia. Blast tube the pmag came on.
I guess my main concern is did I damage the unit by overheating it and thusly making it more prone to shutting itself down? I am perplexed because I have flown the pmag in near 100degree f conditions with the same blast tube set up without any problems. The blast tube is aimed right at the juncture of the pmag and accessory case. Should I add another blast tube with the intention of keeping the accessory case cooler? Or perhaps a cooling fan of some type?
But when I got home curiosity got the better of me and when I tried to restart the hot engine after 10 mins or so the pmag would not work. So now I figure it's the heat and sure enough this evening after flying a 1/2 hr. In 58 degree temp I let it sit w/ the oil door open fired it up and at first the pmag was not working as evidenced by 0 rpm's on the tach, but after about 20 seconds of air being pushed down my 1" dia. Blast tube the pmag came on.
I guess my main concern is did I damage the unit by overheating it and thusly making it more prone to shutting itself down? I am perplexed because I have flown the pmag in near 100degree f conditions with the same blast tube set up without any problems. The blast tube is aimed right at the juncture of the pmag and accessory case. Should I add another blast tube with the intention of keeping the accessory case cooler? Or perhaps a cooling fan of some type?