KJBSouth
Well Known Member
While completing an oil change this weekend, I pushed on the spinner and was surprised it wiggled. The prop was on solid. But, the whole spinner including the backplate to which the cone is fastened, moved. I unfastened the cone from the backplate; sixteen screws around the perimeter. Could not see any problem, but the backplate behind the prop wiggled.
So, yesterday I took off the prop and found this:
The center of the backplate was bolted behind the prop solid to the aluminum crankshaft extension, and the rest of the backplate was floating free.
Apparently 350 hrs of vibrational flexing of the backplate against the edge of the crankcase extension had fatigued the backplate so it cracked. It's not something that could be seen without pulling the prop.
I already have a new backplate ordered and its on its way.
So, yesterday I took off the prop and found this:
The center of the backplate was bolted behind the prop solid to the aluminum crankshaft extension, and the rest of the backplate was floating free.
Apparently 350 hrs of vibrational flexing of the backplate against the edge of the crankcase extension had fatigued the backplate so it cracked. It's not something that could be seen without pulling the prop.
I already have a new backplate ordered and its on its way.
Last edited: