1971 6HP fisherman Prop selection

[thejetman]

So I got this wonderful motor on my 14 foot Alumacraft. It came with a 2 blade, 8x7.25 prop. With me, deep cycle battery and trolling motor in the back it will not reach WOT in gear. In neutral it revs out just fine.I get about half throttle and thats about it. Not enough to get on plane. So, in doing some research, I have found a couple replacements. They are both 3 bladed. One is an 8x6.5 and the other is an 8x5.5
Finding these little props is about impossible as well.
Should I drop all the way to a 5.5 pitch? I plan on putting my wife in the boat as well.
I have removed the giant deep cycle battery and the trolling motor as well, but I haven't tried it. I dont have money to upgrade to a 9.9 yet either.

 

[thejetman]

Side note. The plugs are fresh, fuel is fresh. And it runs like a top. Its not a matter of the condition of the motor. Anyone with one of these and one of these props on it that would like to chime in would be greatly appreciated.

 

[F_R]

6hp might be borderline for planing a 14 footer. You say it is not a matter of condition of the motor, so I won't argue with you. But you sure as hang wouldn't be the first one to say that about a motor that is running on one cylinder. Don't waste your money buying props until you have verified the need.

 

[hardwater fisherman]

I have a 71 johnson 6hp on a 12 foot aluminum. It planes and if I move forward it helps alot. If a second person gets in the boat it will not plane. This is with the same 2 blade prop you have. My motor trolls all day long without any problems..I have seen a few lower pitch props but they were almost as much as what I have in the motor.I have tried a 8 1/8 x 8 3 blade prop of a 9.5 and it preforms about the same. Maybe a little less speed when on plane.

 

[thejetman]

Mine trolls too. But they made a 3 blade 8x5 prop for them. They are discontinued and impossible to find. Its running on both cylinders, I have verified it. There are 2 lower pitched props I have found. One is a 8x5.5 and the other is an 8x6.5. Will going from a 7.25 to a 6.5 be enough. Or should I drop all the way to the 5.5? I have found 1 of each. They are 100 bucks a piece.

 

[jimmbo]

The 6 1/2 will probably be fine. The 5 1/2 is probably intended for sail boats, probably the 6 1/2 as well