Tahoe 215 Deckboat 4.3TKS Prop

[Grace859]

Hello everyone! New to this forum and looking for a little prop advice. I’ve done a little research and think I have an idea of what prop size to try but want to make sure.

1) Performance issue you are trying to correct.
-Boat is currently slow to plane, slow acceleration, and not reaching WOT range.
2) Current prop manufacturer, model, aluminum or stainless as a minimum.
-Stock prop I believe but not sure what brand. It is Aluminum and has a chip on one blade that I will attempt to attach a photo of.
3) Current prop diameter and pitch (required).
-14.25x23
4) Wide open throttle RPM and speed with an average load (very helpful)
-Tested this on two different days with different weather and loads. One day was 4400 max RPM and right at 40MPH GPS. Second day was 4000 max RPM at about 36MPH GPS.
5) Engine/drive make, model, year, and HP
-2008 Mercruiser 4.3TKS (190HP)
-Alpha One Gen 2 Drive with 1.81 gear ratio
6) Boat make model, year, length and weight
-2008 Tahoe 215 Deckboat. 21’6”. Around 3500 pound dry weight.


Im think of going with an Aluminum 19P 4 blade prop but unsure how the chipped prop is affecting my current numbers. I’m not too concerned about top speed. 35 MPH would be fine with me. We use the boat for cruising and tubing right now and plan to add skiing and fishing in the future. I’m open to specific props anyone may suggest, but will probably look around a little and try to find a used one somewhere to try.

 

[Scott Danforth]

23p is a bit steep of a prop for that motor

I dont think you need to drop to a 19p, however a 21p at a minimum

 

[Grace859]

23p is a bit steep of a prop for that motor

I dont think you need to drop to a 19p, however a 21p at a minimum

You think a 21P would even be ok for a 4 blade? Any Aluminum ones under $150 you would recommend?

 

[Scott Danforth]

thinking 21P 3-blade. if you want a 4-blade you will need to test it.

 

[jkust]

The boat is a touch underpowered. Surprised it had that engine ordered with it to begin with. If it was to have a cost saving, carbed engine, I'd have imagined it with a 5.0. Definitely a 23" prop is too much. My previous boat was a similar situation and 23 was too much for that much weight for that engine.

 

[Grace859]

thinking 21P 3-blade. if you want a 4-blade you will need to test it.

Thanks for the help. I’ll see if I can find a shop to try a couple different ones.

The boat is a touch underpowered. Surprised it had that engine ordered with it to begin with. If it was to have a cost saving, carbed engine, I'd have imagined it with a 5.0. Definitely a 23" prop is too much. My previous boat was a similar situation and 23 was too much for that much weight for that engine.

I know the 23” is too much and the boat probably is a little underpowered for its size/weight. That’s why I’m hoping to sacrifice a little top end to improve hole shot by switching to a smaller pitched 4 blade prop.

 

[Scott Danforth]

I know the 23” is too much and the boat probably is a little underpowered for its size/weight. That’s why I’m hoping to sacrifice a little top end to improve hole shot by switching to a smaller pitched 4 blade prop.

for better hole shot, stick with 3-blade and drop your pitch, and go with a vented prop to get the RPM's up.