47ft marine trader props

[Justtls]

Greetings All and thanks for your time.
I'm trying to figure out the best props for my 1987 Marine Trader 47ft tradewinds trawler-motor yacht.
I have 1.75 inch shafts and VOLVO PENTA TAMD40B engines 165 HP each. Does anyone have experience with this boat?
My old props were beyond repair but still handle better than the backup props that came with the boat.
Any help would be greatly appreciated.
Thanks for your time.
Terry

 

[Comodave]

Can you read the size on the bad props? If you can that would be a place to start. Boatdiesel.com has some prop calculators but you have to join at $25 per year. There may be calculators on other sites that are free.

 

[C lectric]

For some help we need to know what you have now, both sets. Diameter, pitch and number of blades. Some photos may help also.
And how did the set you had on now handle? If OK then talk to a prop shop and get an idea.

Have you talked to a prop shop yet about what you had.

If you want to change the props then for starters You should have a laser pointer digital phototach and do some measurements Available from Ebay and Amazon for about $20.00 or so. Dash tachs can be off quite a bit and that can throw off any measurements and efforts to find a good prop.

And yes calculators can help BUT they can be off depending upon what kind of info you feed them. For the best guesstimate get a prop shop to find out what you have now. NOt repair it , just scan it.

 

[Jeff F]

Need the reduction ratio from the transmissions as well.

 

[motion30]

The prop calculator on boat diesel was dead on when I was looking for props

 

[fgarriso]

You ask for prop info.

https://vicprop.com/displacement_size_new.php

 

[Comodave]

You ask for prop info.

https://vicprop.com/displacement_size_new.php

There you go, a freebe.

 

[Justtls]

Thank you all for the info. When I run the calculations it comes out around 20 inch. With 18 pitch. My old props although battered gave me good control and the PO said performance was good. The old battered props were MI Fed. 24 with 16 pitch. 3 blade. I was considering going to a smaller, 20 inch 4 blade with 16 pitch. Thoughts ?

 

[Justtls]

24 with 16 pitch, 3 blade.

 

[Justtls]

BTW. The old props were so badly chipped off that they were barely over 20 inches left and I could still go post to post on 4 corners in my slip to remove lines.

 

[motion30]

I misunderstanding something here, the calculator told you 20-in pitch or 20-in diameter?