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Charles, Marine Mechanic
Category: Boat
Satisfied Customers: 3977
Experience:  US Navy (Ret) Certified Mercury Marine Tech with over a decade of repair experience.
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I have a 1996 240 sea ray sundancer 5.7L 210hp I am running

Customer Question

I have a 1996 240 sea ray sundancer 5.7L 210hp I am running ma 14.5 dia 18P I am at 5500ft only running
JA: Sometimes things that you think will be really complicated end up being easy to fix. The Marine Mechanic I'm going to connect you with knows all the tricks and shortcuts. Tell me a bit more about what's going on so the Marine Mechanic can help you best.
Customer: 4200rpm want to go to 4 blade SS what are my choices?
JA: Is there anything else important you think the Marine Mechanic should know?
Customer: I do not think so.
Submitted: 2 months ago.
Category: Boat
Expert:  Charles replied 2 months ago.

Hello, my name is***** will assist you.

Let me run some calculations. Ill have an answer for you in just a few minutes.

Expert:  Charles replied 2 months ago.

You can run just about any of the Mercury 4 blade props, except for the Bravo 1. Drop the pitch down to 16-17 and you should get in the 4600 RPM range with a top speed of around 39 MPH. I figured this using several different drive types and gear ratios and all were pretty close to these results here.