15 hp Mercury prop question

[Seamates]

I have a 15 hp Mercury on a 14 ft. jon boat. The prop is a B9 X9P. I have no idea what the letters mean. Normally this pushes the boat like a bat with just me, the dog and fishing gear. However, I am about to take it on a trip where there will be 3 men and all our camping gear in the boat loaded right to the max or maybe a bit over. I need the motor to really push with that much weight. Should I just go with a 9 x 8 or should I bite the bullet and go to a 9 x 7 to be sure. Would you recommend putting a tachometer on the boat so I don't over rev the engine by bringing down the pitch.

 

[steelespike]

Re: 15 hp Mercury prop question

9" diameter X 9" pitch.Perhaps the B is actually a D?
If you have the time get an induction tach and get us the info required in the stickys at the top of the prop forum.
You do need the tach to be sure you don't over rev the motor.Its highly unlikely it will plane with all that aboard.
The 7" will surely let the motor rev and it should be happier than straining with too high a pitch.
If its a 1436 planing isn't likely If its a light 1448 or 52 maybe.?

 

[Seamates]

Re: 15 hp Mercury prop question

9" diameter X 9" pitch.Perhaps the B is actually a D?
If you have the time get an induction tach and get us the info required in the stickys at the top of the prop forum.
You do need the tach to be sure you don't over rev the motor.Its highly unlikely it will plane with all that aboard.
The 7" will surely let the motor rev and it should be happier than straining with too high a pitch.
If its a 1436 planing isn't likely If its a light 1448 or 52 maybe.?

It is a 1436 and I don't think it has a prayer of planning out. But I blew a head gasket on another motor on my last trip from lugging the motor and I don't want to do that again. There is nothing worse than being in the middle of nowhere and having the motor crap out. I just want the motor to be happy. Thanks I will be ordering a 9 X 7 and a tach today.