Oil cooler mounting

Working on the baffles. When I mounted the oil cooler to the baffle I discovered the lower inside nutplate rubs against the #4 cylinder cooling fins.



Is this a problem? Should I file down the nutplate?

Thoughts?

Strike

Contact between the nutplate and the cooling fin should definitely be eliminated. However this photo also seems to depict insufficient thread protrusion through the nutplate. I believe AC43.13 recommends 1-1.5 threads through a nut, and I assume that applies to nutplates as well.

The options to address this aren't all that attractive. You could move the entire oil cooler up, which would require some pretty extensive surgery on the rear baffle. Alternatively you could file the nutplate and live with the reduced thread protrusion and the ever-so-slight possibility that the bolt may back out in service. Another option is to slightly trim down the interfering cooling fins on the cylinder. I'd suggest hearing opinions from some of our resident engine gurus before going that route.

Keep us updated!

Just get out the die grinder and cut the cylinder fin to give sufficient clearance and get a longer bolt.

I modified the fin slightly with a "rounded" cutout similar to others shown in the picture... That way I could achieve a bit of thread showing. I'm not an engine expert however..