[KazooRV-9A]

I'm installing a Sensenich 70CM7S9 prop on my RV-9A with an O-320 engine. The prop bolts are 7/16", and the bolt holes in the Van's S-605 SEN front spinner plate as-supplied are 3/8"...
Drawing C4 shows that the S-605 SEN front plate can be used with either an O-320 or O-360 engine, The drawing seems to indicate that there can be either 7/16" or 1/2" prop bolts (see the washer callouts) depending in the engine used.
It appears that the S-605 SEN plates are supplied with 3/8" bolt holes and that you are then supposed to drill them to the correct size for your prop bolts??
There's nothing noted in the written instructions for the prop/spinner installation.
Is this what builders are doing? if so, what methods are being used to maintain minimum/acceptable runout for the spinner?
Tnx,
AC.

 

[rvbuilder2002]

I'm installing a Sensenich 70CM7S9 prop on my RV-9A with an O-320 engine. The prop bolts are 7/16", and the bolt holes in the Van's S-605 SEN front spinner plate as-supplied are 3/8"...
Drawing C4 shows that the S-605 SEN front plate can be used with either an O-320 or O-360 engine, The drawing seems to indicate that there can be either 7/16" or 1/2" prop bolts (see the washer callouts) depending in the engine used.
It appears that the S-605 SEN plates are supplied with 3/8" bolt holes and that you are then supposed to drill them to the correct size for your prop bolts??
There's nothing noted in the written instructions for the prop/spinner installation.
Is this what builders are doing? if so, what methods are being used to maintain minimum/acceptable runout for the spinner?
Tnx,
AC.

Some models of the O-320 use 3/8" diameter propeller bolts, so the part is produced with that sized hole.
If you have the 7/16" bolts you need to enlarge the holes to that size.
A step drill in a drill press is the best method to help assure you don't drift the position of the holes.

 

[KazooRV-9A]

Thank you for the answer!
I had called Van's builder support and in viewing their drawings, the support person didn't really know why the front spinner would have been manufactured with 3/8" holes. And neither the C4 drawing nor the written instructions indicated anything about opening up the holes for larger diameter bolts. That would have made it simple to understand.
So I just took the time to ask. In the end I used a step drill as suggested and opened the holes to 7/16" for my prop bolts.
Maybe Van's will add notes to their documents at next revision,...
AC.