prop numbers and correct prop pitch

[dcar00]

I have 92 Force 90HP and a 24Ft Pontoon boat.

WOT is 5000rpm. Does anyone know the correct prop pitch for ths setup?


I have a prop with these numbers stamped on the outside

M1961
C.M.M is also stamped

Alson the inside of hte prop on the ring where the spline goes in "P692" is stamped

Any help would be appreciated.

I also mesure the prop blade from the back to the front(if you were looking at the prop from the side) and it measures 5"

 

[walleyehed]

Re: prop numbers and correct prop pitch

That's an original Force 13-1/2X15 aluminum.

 

[dcar00]

Re: prop numbers and correct prop pitch

Thanks Walleyehed,

is a 15inch pitch OK for my boats set up?

92 90HP FOrce on a 24ft pontoon boat 5000RPM WOT

It seems I'm seeing people on this forum saying it should be lower

 

[steelespike]

Re: prop numbers and correct prop pitch

I'm no expert but it appears most like to run at least 500 rpm above the developed horsepowqere rpm.Your motor i believe is 90 hp at 5,000 rpm.
My 88 50 Evinrude is rated at 5,000 rpm.It runs at 5,200
wot on my 18 pontoon as set up by a very expierenced dealer.
You might want to try raising your motor vertically one hole brfore going to a different prop.
I don't think your set up is bad.It's just right at the low end.
you may want to confirm your rpm by borrowing a tach and double checking.

 

[dcar00]

Re: prop numbers and correct prop pitch-pontoon

Re: prop numbers and correct prop pitch-pontoon

steelespike,

Good thought about raising the motor. I'll check it.

I get 5000RPM at WOT. i do have a little build up on the toons which I should clean

Is 13.5 inch diameter 3 blade good for a 92 90HP force 24ft pontoon that gets 5000RPM with one person on board at WOT?

Thanks

 

[walleyehed]

Re: prop numbers and correct prop pitch

dcar, the WOT should be atleast 5250 with a normal load....not by yourself...