View Full Version : Prop!!??

06-01-2005, 08:05 AM
Hi everybody!
Just bought my first Mastercraft! A nice X-9 2003 with a MCX, but I have a little question about PROP... What should be the right size of the prop when the boat was new. What size Master put on it normally...

Now I have a 12.5x12... is it OK?!

I'll put a picture on newbies thread next week, I'll put it on water this weekend... :D

Thank you for your help...


east tx skier
06-01-2005, 12:12 PM
From my conversations with Eric Johnson, a semi-educated guess is 13x11.5. I would suggest you PM him though.

06-01-2005, 01:38 PM
In determining prop size it is most important to know what rpm's your turning at wot and what size prop is on it. If you give eric at oj or the folks at acme that information they can give you a recommendation.

06-01-2005, 03:41 PM
I believe in 2003 the factory still used the cast OJ prop. For your set up I think that would have been the good ol 13X13. If you are planning on upgrading though I would step up to the new CNC that OJ or ACME recommends.

06-01-2005, 07:11 PM
The stock prop provided by Mastercraft for an X9 with a 1:1 transmission is a 13 x 12.5, 4 blade Nibral with a .080 cup.

Does your 12.5x12 three blades or four blades?

The application chart shows the corresponding 3 blade prop to be a 13x12 for an X9.

06-02-2005, 01:03 AM
I forgot a little detail hey!?
It's a 12.5 x 12 four blade.
Thanks again!

06-02-2005, 01:55 PM
The 12.5 X 12 LC 4-blade XMP is the standard propeller for 1:1 transmissions with the MCX. If you are looking for a 3-blade I would suggest our 13 X 11.5 LC XMP. If you have any other questions please let me know. Eric

06-06-2005, 07:33 AM
Thank you guys specially Eric who relieve me about my prop...
We tried it this week end it's a great machine!
I'll try to get picture next week... now it's the week let's work to pay the baby!!
Have a nice week everybody!
Stef :steering:

06-06-2005, 12:50 PM
So I'm guessing that you have a CNC prop?

The 12.5x12 CNC (OJ's XMP) may be the standard prop for your setup but it was not what was supplied by the factory here on the west coast in 2003. Nibral 13x12.5 was the factory prop at the three dealerships here in 2003.

Sounds like your original owner replaced it. Lucky :steering: