Prop for 75 hp merc.

[canadianfcat]

So I've got a 1990 Spectrum Blue Fin 1606 (a full floor front casting platform side console boat )with a 1992 Mercury 75 hp 2 stroke.The 75 hp is max for the boat

The boat tops out at 32 mph.(don't have a tach) and eats a ton of gas.It planes out quick but performs the same whether by my self or fully loaded with the family.By adding the wife and kids (9 and 12) it may only slow by 1-2 mph.
The only numbers I can find on the outside of the prop is OP47811 if that tellls you anything.

 

[sublauxation]

Re: Prop for 75 hp merc.

Have you taken the prop off to look for more numbers? Ultimately you're going to need a tach to see where you're at.

 

[steelespike]

Re: Prop for 75 hp merc.

Numbers usually appear near the base of the blades or under the prop nut.
Check out the induction tachs like the Tinytach.
A gps is best for speed. Also read the stickys at the top of the prop forum.