Prop pitch 1971 85 hp Mercury

[redfisher1]

I just bought a 15' Vampire bass boat 1973. It came with a 1971 Mercury 2 cycle 85 hp. I don't know much about the boat and can't find any info on the web. I would think it weighs about 550 to 600 lbs. The engin came with a
13x23 three bladed prop. The previous owner was told by his tech. that the engin is over pitched. I have not had her on the water yet but have ordered a
new Hustler 13.25x17". I would love to know more about the boat and if this prop would work well before I install it.

 

[steelespike]

Re: Prop pitch 1971 85 hp Mercury

Can't tell you about the boat There doesn't appear to be an 85 in 71 my info indicates 72.Anywho;I think the 17" hustler may be too much as well.
The Hustler I think is a little too much pitch and it is an agressive prop.
If the 21 is in good shape you could get some specs with a test run.
We need the max rpm and speed with the prop size and the specs we can suggest a prop.If you can exchange the Hustler do a test run with it.