Custom Made 12.5" Diameter, 15 tooth, 13 pitch prop?

[ernrays]

I use my boat on a lake that is about 9000 feet above sea level. That impacts performance significantly. If I get more than 4 adults in the boat, or a full tank of gas, I cannot get the boat to plane on the water. The RPMs go up to about 2100 and no further. The boat: 19' Bayliner, open bow. One potential solution is to change props. I am already using a 15 pitch cupped prop on the 125 HP outboard Force engine (1985). As near as I can tell, no one makes a 13 pitch prop (probably due to low market demand or something).

Anyway, does anyone know if there is a company that makes custom aluminum props (12.5" diameter, 15 tooth, exhaust isn't through the prop, probably don't want the prop cupped)?

 

[Chris1956]

Sometimes there are specs for high altitude carb jets that restore some power and improve fuel economy. That might be a first step.

Not sure about props for Force motors. Newer Force used Merc gearcases, I think.

 

[fishrdan]

A prop shop should be able take some pitch out of your current prop, but most likely not enough to do any good though.

See if a lower gear ratio lower unit is available for your outboard, like from a 85 or 100 HP, if they built those in the same family of your Force. On my 140HP Mercruiser with a 1.98:1 lower unit, there are 2.21:1 (or something like that) gears available for high altitude "only" operation. This isn't common, but if you are going to be solely operating at high altitude, it's a good option.

But honestly, you're asking a lot from your combo and a load of 4 adults at 9000' as that 125HP is down to around 90HP when altitude takes it's toll... I've had my 18'er/140HP combo up at 8800', and it's a dog with 2 adults and 2 kids, 15P prop and re-jetted carb, planes in 15 seconds.

 

[steelespike]

Standard jet on the 125 is .937.I was able to find jets for the Chrysler 125s Tillotson TC-6b.Carb standard is the same as the Force.937 above 6000 is .086.
number 013949.