Prop Identification and Choice

[ritkit]

I have a Sea Ray 2007 185 sport.

2006 Mercruiser 4.3l 190Hp Alpha One, I think it is gen II. I damaged my prop pretty severely last week and would like to get a new one.

WOT is at 4435 rpms. WOT range is 4000-4800.

I kind of want to get better off the line acceleration, without sacrificing the top speed much.

Additionally I am slightly confused what prop I currently have, so I have attached a picture of what looks like the serial number. I sanded it down to make it a little easier to read.

 

[MARV1]

Re: Prop Identification and Choice

Looks like a 23" pitch, drop down to 22" and gain 150rpm.

 

[jestor68]

Re: Prop Identification and Choice

Your WOT rpm range is 4400-4800 rpm.

You need to go to a 21 pitch to get the rpm up close to the maximum for best all around performance.

The 21 will attain about the same top speed, while providing much improved acceleration and better responce to the throttle.

 

[ritkit]

Re: Prop Identification and Choice

What about going to 21 or 20 with a 4 bladed prop?

 

[theBrownskull]

Re: Prop Identification and Choice

A four blade might be slower on the top end. I would test out a 21 three blade and a 21 four blade, possibly a 19 four blade. A stainless 21 might get you where you want to be. Some people have been going with the Mercury "High Five" prop. for the 4.3.

 

[ritkit]

Re: Prop Identification and Choice

I would prefer not spending $400 on a prop right now. Besides I cannot find many places to purchase it.

Besides what benefits do the 5 blade prop give over a 4 and a 3?

 

[Slip Away]

Re: Prop Identification and Choice

The 2007 185 Sport came with a 14.25" x 21p #-Blade aluminum prop. That is the best prop for your boat for overall performance. It will
hit max RPM. Buty a Michigan Wheel part # 992005 Vortex 3-blade aluminum. It is affordable too.

 

[ritkit]

Re: Prop Identification and Choice

That is what I thought the boat came with. I am the second owner and it had the 23" which slightly confused me. Thank you.

 

[Slip Away]

Re: Prop Identification and Choice

Ooops.... I stand corrected. According to Sea Ray prop chart, if your drive has a 1.81:1 drive ratio, 190HP, stock prop was a 14 x 23p Black Max. I still think a 21p is what you need since you are not getting max RPM.

http://www.searay.com/boat_graphics/electronic_brochure/Company1729/1C1_25_74DEIP4PZ12.pdf

 

[ritkit]

Re: Prop Identification and Choice

Ya. I took your advice on the Vortex. Hopefully it does what I want.

Also impressive google skills on finding that doc!

 

[Slip Away]

Re: Prop Identification and Choice

That Vortex works great on many boats with alpha 1. It is what I have on my 2011 Monterey 204 with 5.0L V8, when I am not using
the 992204 14 x 20p 4-Blade Vortex. I'm confident you will like it.

 

[theBrownskull]

Re: Prop Identification and Choice

ritkit,

I don't blame you for not wanting to speed a lot of cash. Regarding your question about the "High Five" prop., I have been told by boat owners who use it, that it is the way to go. I don't have one so I cannot tell you personal experience. Check out mercury's link below.

High Five | Propellers | Mercury Marine