Prop flange bushings.

[Drifteral]

Have a lycoming O-320-A1A with 3/8 flange bushings. Need to convert it over to 7/16 bushings but i'm having trouble finding the part #'s. Reason is my prop has 7/16 holes.

If i'm reading the parts book right I need the following lycoming part numbers:

1 ea 72065
3 ea 72063
2 ea 72064

If this is correct my questions are:

1. Why 3 different part #'s?

2. Where to get them reasonably priced?

Thanks
Al

[az_gila]

This may be a better reference than the parts manual -

https://www.lycoming.com/sites/defau...20Location.pdf

The three numbers are for different lengths and one of them is the "index" bushing and fits into a slightly larger hole in the crank flange.

Try your local engine rebuilders for used parts - they usually salvage them from scrapped cracks.

Check the thickness of the prop flange, it does affect the part numbers, but it's covered in the SI linked above.

Check the bushings you are removing to see if there is a Pxx number on them. This would indicate an oversize drive bushing.

[Drifteral]

Thanks Gil,

That help a lot!