More pitch orbigger prop

[prlwng]

60 hp merc. New. 1650 crestliner fishawk side console.

when I got the boat had a 4 blade on it. Engine would wind up and then slowly speed up. Went to 3 blade. Now jumps right onto plane, has good speed. About 28 mph.

wondering about trying a larger prop, 3 inches from top of prop to trim tab. Or going to more pitch. The reason being is that even in a fast current, run many times against 5 mph plus current, engine is still not working. In other type vehicles, and i/o boat, one can feel engine working. Top speed is enough for me. Just dont like running higher than needed rpm when crusing to fishing spots.

Thanks all, figure someone here has tryed props.

 

[Silvertip]

You don't select props by what your ears or your butt is telling you about the engine. If your boat doesn't have a tach, get one. It is the only way to tell whether you have the correct prop, and if not, which way you need to change PITCH. You also don't shop for props by diameter. You buy a prop for your engine (hub specs), then material (aluminum or stainless) then cup or no cup, and when done with that, DIAMETER is taken care of automatically. Look at the specs for any prop with varying pitch numbers. You will see that diameter changes slightly with pitch change. This is called "design". You don't stick larger diameter props on lower units that are not geared or sized for them. You can certainly reduce RPM with a prop with higher pitch. But if that engine cannot operate at or near the upper end of the recommended rpm band, you are lugging the engine and it is not good for the engine or fuel economy.​

 

[prlwng]

Oh yes, 5500 to 6tho way to easy. Then back off throtel. About 28 mph at that rpm. Gps fishfinder. 1.83 ratio. Hardley uses gas.

 

[Silvertip]

You may be experiencing "blow-out" which is the prop digging a hole in the water until it can get a bite and then you are off. You don't mention the pitch of the current prop but it sounds like you could use a prop with more pitch. 1.83 gear cases on two strokes normally ran 10-1/2 inch diameter props. A prop with more pitch for that gear case should put top end where you need it and get you out of the hole without blow out. Is the motor mounted too high on the transom?