Prop Fitment on 90 ETEC

[blkfalc4]

E90DSLAAA

I was attempting to use a Merc Spitfire X7 12.8 x 21p on my 90, but the prop hub where it's suppose to fit inside the lower's housing doesn't.

Doesn't the 90hp have a 4 1/4" lower?

I measured the prop at 3.980" but the opening is only 3.850"

Am I missing something? A defective (brand new) prop ?

Or just an oddball lower that Merc props won't work?

Thanks for any insight

[Bighare2]

OD is closer to 4.1 for the V4 S2 type lower unit, 20 in shaft.
OD is closer to 4.4 for the V6 O type lower on the 25 in shaft.

[blkfalc4]

Measured OD at 4.123, so 4-1/8

The 90 is an I3 which shares same lower as I2 and V4

[blkfalc4]

Thanks for the reply, btw.....
So I guess Mercury props are a no go on these lowers.

Maybe I'll see if I can turn it down.

[blkfalc4]

Anyone know actual I.D. of the housing on the S2 lower.