I had two instances where prop bolts galled in the first 20 hours of operation. The second time, one of the bolts seized in the insert so the head had to be cut off in order to get the prop off. New inserts were installed by Saber each time. The bolts and insert threads were cleaned with compressed air, then installed dry and torqued to 40 ft./lbs. and checked with two torque wrenches. I've since waxed the threads and torqued to 35 ft. lbs. with about 50 trouble free hours on them now. I had been running 4 Belleville washers per bolt, but currently am running shorter bolts with no Bellevilles. I'll need to get longer bolts to run Bellevilles again. In the mean time, I'll judiciously check prop bolt torque. I'd like to get these bolts checked to see if their hardness is what it is supposed to be since there have been reports of counterfeit grade 9 bolts.
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| Looks like the threads were dinged before plating. |
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| Ding on end of bolt. |
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| Some dings on the ring on the head of the bolt. |
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| Damaged threads. |
The plating on the threads wasn't consistent on some bolts.
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