Whaler Central - Boston Whaler Boat Information and Photos

Posted by dbcollen on 04/13/13 - 9:54 AM

I have a 13' whaler and just put a 15 hp merc 4 stroke on it, the prop that came with it is a 9.5p hi thrust model the # on the prop reads "10 9.5p" at the end(most #s unreadable) it hits the rev limiter at 5700rpm wot @ 15 mph. the engine is a 2000 model, I think 2.0:1, 8 spline and has a wot range of 4500-5500 rpm any suggestions?

Edited by dbcollen on 04/13/13 - 10:07 AM

Posted by Tom W Clark on 04/14/13 - 4:50 PM

Is your 2000 Mercury 15 four stroke a BigFoot model or a regular gearcase model?

Posted by Tom W Clark on 04/15/13 - 7:59 AM

Dustin -- I've never heard of a prop with 9.5 inches of pitch. There may be one, but not from Mercury.

At any rate, if you did have a 9.5" pitch prop and you're only going 15 MPH and the motor does have a 2:1 gear ratio, then the prop is simply slipping and not pushing. Calculated prop slip is about 45 percent.

What is the diameter of the hub of the propeller at the forward end?

Posted by dbcollen on 04/15/13 - 11:31 AM

the boat is 100mi from me right now, I will call my friend and have him measure it.
I was told by the local marine shop that they recommended the Solas Amita 3 Aluminum Prop 1111-093-11

Edited by dbcollen on 04/15/13 - 11:33 AM

Posted by Tom W Clark on 04/15/13 - 12:23 PM

OK, if that prop fits then you do have the 2.5" hub (regular) gearcase.

The Solas Amita # 1111-093-11 is a 9-1/4" x 11" three blade prop. That is way too much pitch for your application. You'll want a 9" pitch probably.

I have a new-in-the-box 9" x 9" Stiletto Ariva aluminum three blade that would be a nice fit, but for a 13' Whaler I actually think a 9-1/4" x 9" Solas 4 blade (part #1113-093-09) would work best because you want as much blade area as you can get.

Here is one source:

http://www.firstchoicemarine.com/p-22...93-09.aspx