2-blade vs. 3-blade prop and cooling

[Tom Milke]

Hi All,In researching a cooling problem I am having with my Renault 8HP inboard, I've come to notice that the boat was probably originally delivered with a 2-blade prop. The current prop on the boat is 3-bladed.Does anyone have a specification for the original propellor?Does anyone have an informed opinion on whether a change in prop might cause the engine to overheat?Tom Milke

 

[Pat McCartin]

not that farfetched of an idea

In theroy it "could" be over working that little engine. YOu'll need to see what the maximum RPM you can reach is with the 3 blade. I'd look tword other causes.

 

[David Foster]

Call a prop shop

Any good prop shop would run the numbers for you. The original two blade prop on our '77 model has the same pitch and diameter as is shown in the model info of this site.The prop shop will want to know the pitch and diameter of your three bladed replacement.Although I live in Ohio, I have worked with Bay Prop in Alameda, I think.DavidLady Lillie

 

[j Cianflone]

3 blade

I have switched to a three blade on my rc8 1980 h27 and have not had the engine run any hotter.