Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: Need Prop for 15 whaler

Posted by Logeypogey on 08/27/14 - 4:20 PM
#1

Hi all this what i have. 1982 15' whaler sport , 1993 Merc 75 3cyl 2 smoke, 1.75 gear. Currently boat has a quicksilver 13x19 aluminum prop on it my father destroyed it. boat was fast as hell out of hole and while running. But after 3/4 throttle there was no change in speed it just reved up more. No speedo or working tach. I have to buy annother prop so I want to get a little closer to where i need to be. I realize without a working tach it makes it harder.

Posted by Logeypogey on 08/28/14 - 9:46 AM
#2

Quick edit gear ratio is 2.31:1

Posted by huckelberry145 on 08/28/14 - 10:43 AM
#3

You will thank yourself after purchasing a stainless prop. I liken it to having an automatic transmission rebuilt. There was so much slip in the bad one that the new one makes both the performance and gas mileage improve. Also, right now is a good time to install a tachometer on your console. It is the opinion of many that most every boat needs one, especially when searching for the right prop. I was blessed to have a local prop shop that would let me try several props before I found the best one for my application.

Posted by Logeypogey on 08/28/14 - 12:56 PM
#4

huckelberry145 wrote:
You will thank yourself after purchasing a stainless prop. I liken it to having an automatic transmission rebuilt. There was so much slip in the bad one that the new one makes both the performance and gas mileage improve. Also, right now is a good time to install a tachometer on your console. It is the opinion of many that most every boat needs one, especially when searching for the right prop. I was blessed to have a local prop shop that would let me try several props before I found the best one for my application.


I compleatly agree with you on using a stainless prop. However if the old man hit what ever he hit with a stainless prop we would be buying a lower end as well. Also not his first rock pile. Im just trying to get it a little better than what it was. The boat really does not get used much any more. Maybee 15 gallons of gas/year.

Posted by tedious on 08/28/14 - 2:47 PM
#5

The idea that an aluminum prop will save your drivetrain when you hit something is an old wives' tale - often quoted but incorrect. A member here described two cases of hitting the same obstruction - an underwater post. One hit was with stainless and the other aluminum. The gearbox was toast in both cases.

Get a good stainless prop. You'll be amazed at the difference in performance.

Posted by jamesgt727 on 08/29/14 - 7:10 PM
#6

i would go with a 20" merc or quick Laser II 13.25" x 20" pitch for great top end, if you want a good general stainless, grab a mercury vengence, which is a stainless version of the standard aluminum prop. I used an 18" version of that prop on mine for a bit, works good. find used props to test, you can always have them reconditioned for $100 at general propeller in Bradenton FL. Use a rubber torq-thrust III hub kit to avoid gear rattle at idle.

Posted by brwntrt on 08/30/14 - 1:33 PM
#7

I'll be interested in hearing your results with a prop change. I run the same whaler with the same Mercury at 6000'. The boat came with a 15 pitch Quicksilver that gave the boat a head snapping hole shot and a top speed of about 40mph with a little over rev. I switched to a 17 pitch last year and the boat still has plenty of pull to get a wake boarder up easily, and a noticeable drop in rpms at mid range cruising speeds, but still tops out at 39.5 mph. That model Mercury just doesn't seem to be built for high end performance. After about 4800 rpm it just leans itself out.

Posted by jamesgt727 on 09/05/14 - 10:51 AM
#8

I must correct my statement, I run the props piercing the surface on a jack plate to get the RPM, for instance, my hot 90, is running a 28" cleaver at 5900 rpm with a 2.33 ratio, speed cone with low water pick-ups and about a 60 ft rooster tail. Its topping out higher, but I have hull mods involved too.

Posted by dgoodhue on 09/06/14 - 4:15 AM
#9

Your top speed should be around 45mph. I would check the engine mounting height to make the motor isn't mount all the way down.