Bearing hole to case alignment ?

[N360DF]

Folks,

Any engine builder here ? I have started the building of my 360 and first I do a test assembly.

I discovered the holes in the bearing aligns very badly with the holes in the crankcase. Anyone who knows about this is normal ?

https://lancairtalk.net/download/file.php?id=12721&t=1

[rocketman1988]

When I rebuilt my continental o300 I ran into this. After several calls to continental, I was told this was pretty much normal(!?!). They did say that if the case was still disassembled, it is possible to “use a countersink to create a larger diameter hole” in the case journal. They also said that if you could see 30% of the case journal hole through the bearing hole, it was ok.

Take it for what it’s worth. I opted to slightly enlarge the holes with a countersink. Engine ran fine and had north of 1000hrs on it when I sold the airplane...

[mahlon_r]

It's normal for them to not be perfectly aligned.
Good Luck,
Mahlon