I bought a 77 model evenrude 70 hp motor to put on my 24' aquapatio pontoon and was unsure of what prop should be on this it had a 40 hp force outboard befor so I cant use that prop any suggestions
Dodge, look on the back of the boat for a plate that will tell you the weight of the boat and how much weight you can carry.
The 17" pitch prop has way too much pitch to push that boat and keep the RPM anywhere near the RPM recommended range and it will load the engine and shorten engine life very much.