General question on Props

[Trucker-Boater]

The boat is a 1964 Glasspar, 14-15 footer. Not used for skiing. Just a toy that I use to cruise the lakes.

Currently (and removed because it spun) it has a 19p on a 85 hp Merc.
My curiosity is such I would like to try some different props.

I can get a used 19p for $60, and a used SS 23p for $75.

My curiosity is the 23p. What would a 23p do to the overall enjoyment of this old runabout? Make it uncontrollable? Lug the engine? I mainly just cruise along at 30 mph, throttle at about 3/4 or less. Checking out the beauty of the lake.

Ideas?

 

[QC]

Re: General question on Props

We need your RPM at WOT to answer. The concern would be lugging the engine. A jump from a 19 aluminum to a 23 ss is a big deal. Prolly more than 800 RPM loss Take a read of the stickies above maybe for a starting point. I'd be very surprised if your motor could pull a 23 no matter what though.

 

[Sea Rider]

Re: General question on Props

Would have been very helpful to know achieved max wot rpm with current prop, and going from there selecting best +,-pitch for perfect boat/engine optimization for your boating needs. With spun hub, mission impossible..

Happy Boating

 

[Trucker-Boater]

Re: General question on Props

My favorite boat shop sold me an 18 SS, a 21 SS and an aluminum 23p. I hit the lake today. The 18 pops this boat out like a cannon. But the 21 is better all around. I put the 23 on later in the afternoon when the wind was up and it was somewhat choppy.

It planed out slower but the engine sounded like it was straining to keep at a steady 40. I will keep the 23 and return the 18.

I wished this boat had a tach. I have no idea how to hook a tach up to a 1976 Merc 85hp,

 

[steelespike]

Re: General question on Props

Look up induction tachs simple hookup just be sure to get all info and tell them its going on an outboard.
Just guessing there might be a connector in the remote for a tach,What year is the motor?
If you get us your wot gps speed and your prop size we can get a very rough rpm estimate.

 

[Trucker-Boater]

Re: General question on Props

1964 Glasspar with a 85Hp Merc outboard - Imgur

1976 Merc 85Hp on the back of a 63-64 Glasspar