Prop Advise

[ramrod5000]

Need some help choosing a replacement prop.... I have read a ton of post and tried a bunch of the prop selector websites. But wanted to get some real world advise. I have a 1993 maxum pleasurecraft 18xr with a 3.0 4 cyl inboard/outboard aplha one. I use it 99% for going to lake mohave for transporting the family from the dock to a cove..I rarely pull a skier or a tube, but would like to be able to. Can I please get some advise on a good all around prop size ??? thanks in advance !!!

 

[usskydvr]

Re: Prop Advise

What is your current prop and what is your wide open throttle RPM with the
normal load (people,gas,cooler,gear,etc)?

 

[ramrod5000]

Re: Prop Advise

If recall correclty I was at like 4800rpms... The prop thats on it now is a 14.5x9 . But I banged it up lat time I went out.

 

[usskydvr]

Re: Prop Advise

Ok the 3.0L WOT RPM range is 4400-4800 so you are already right at the top. Are you sure about that prop size? If you take off the prop nut there should be a part number stamped under the tab lock washer, on the prop hub.
(sometimes the dia and pitch is stamped on the side of the prop hub itself)

 

[ramrod5000]

Re: Prop Advise

Yup that's what's the stamp reads. It's a Solas

 

[ramrod5000]

Re: Prop Advise

Yup that's what the stamp reads. It's a Solas

 

[ramrod5000]

Re: Prop Advise

Any suggestions ?

 

[usskydvr]

Re: Prop Advise

Although Solas did make a 9 pitch prop that would fit the Alpha outdrive it was actually intended for some of the outboard models. I just find it hard to believe you would need that low of a pitch on your boat.
Can you post a pic of the 14.5 x 9 stamp? Are there any numbers on the prop ANYWHERE? If this REALLY is a 14.5 x 9 then I would recommend going
up to an 11 which should drop your RPM about 200 which would put you in a safer WOT range.

Side note: (with only that 3.0L (135hp) on the 18ft Maxum and 3-4 folks, pulling a skier will be tough and the 9 pitch is the best bet. The tube will not be a problem.

But again, something just seems wrong here. I have NEVER seen a 9 on a
sterndrive runabout. only big pontoon boat.

 

[Tail_Gunner]

Re: Prop Advise

19...........9...........:d

 

[steelespike]

Re: Prop Advise

I agree, most likely a 19" pitch. Changing to a 4 blade 19" will put your rpm at 4600 to 4700 and give better hole shot for skiing and such.It will stay on plane easier
and have better control at the dock.