Which is a good Prop for a Monarch Bassboat

[ssuurrss]

I have a Monarch 16ft bassboat which has a 1977 55HP Evinrude Model 55773D Motor. What is a good diameter, pitch, for say a reasonable speed at 25 to 30mph? right now, I have a badly dinged (previous Owner) prop that barely makes 8.5mph top speed at full throttle. Any help will be greately appreciated.

In the same motor, I have a question on charging. We took the boat out yesterday with a fully charged battery. But about 45 mins in, the motor quit, and the fish finder said Low voltage, So, my question is, does this motor charge the battery?

 

[usskydvr]

Re: Which is a good Prop for a Monarch Bassboat

I'd try a 15 pitch 3 blade. (Diameter is a design function of the mfg)
Your engine should charge the battery.

 

[ssuurrss]

Re: Which is a good Prop for a Monarch Bassboat

I'd try a 15 pitch 3 blade. (Diameter is a design function of the mfg)
Your engine should charge the battery.

Does the Diameter of the prop make a difference? In speed? the bigger the diameter the faster it is? keeping prop pitch constant?

This weekend, I took the motor cover off, and realized that the wire from the rectifier going to the positive terminal of the solenoid is disconnected. I re connected it, and now will have to try it out.

 

[BravoEchoLima]

Re: Which is a good Prop for a Monarch Bassboat

I have been looking around sites trying to find you some answers. I am new to this forum and figured I'd offer what I can find.

http://www.rbbi.com/folders/prop/propcalc.htm has a calculator if you have 4 of the variables it can answer some MPH questions. I just found this online.

http://motor-boats.suite101.com/article.cfm/boat_propeller_basics

this site can give valuable insight. I read through it and it defines what each property of the blade will do. Could help your decision.

 

[usskydvr]

Re: Which is a good Prop for a Monarch Bassboat

Theoretically assuming all other design particulars are the same (cupping, rake, pitch, etc) just going to a larger diameter will have a minimal increase in speed, but a larger increase in hole shot. (larger blades initially give more push, but also increases drag which can limit max RPM)