prop ?

lofosho_97 · Outlaw Joined: 05 Aug 2005 Posts: 180 City: lexington

I have a mercruiser 4.3 in an 18ft boat. It has an 23 pitch 3 blade prop.Im going to add weight to the boat and want more pulling power. I was going to go with a 19 pitch prop. Funds are real tight right now. So I was wondering if I should go with a 19 p stainless 3 blade or a 19 p aluminum 4 blade. These 2 seem to have the same price range.Also whats the diffrence between 3 blade, 4 blade, and even 5 blade props.Is 19 p low enough?

Vampyre · Addict Joined: 12 Oct 2004 Posts: 622 City: Ooltewah, TN

Well, I am in the same boat as you (pun intended).
Same size boat and engine. I currently have a 3 blade 21 pitch SS prop.
I am going to get a 4 blade 17 pitch SS prop. That runs about $300 new at a local shop, but I am going to look around. The aluminum is about $120.

The aluminum will probably flex and slip too much with the added weight. I am not crazy about spending the extra money on the stainless, especially since where I ride, there are really not many stumps, etc.

I know people will say buy a 5 blade Merc HiFive prop, but from what I see, those are like $550 or so.

If possible, can you try the props out on your boat before you purchase? I have a prop shop that will let me do that. A lot will depend on your RPMs, and also how much weight you will be running.

lofosho_97 · Outlaw Joined: 05 Aug 2005 Posts: 180 City: lexington

I will be running 600lbs in the front and 150-250lbs in the locker.No more than 700lbs of people weight at one time.would a 19 pitch be low enough to get a good hole shot with all that weight or should i go lower.I wont be running that much weight all the time thats just the most i will be running.you could take 200-300lbs of that on an average day.

Vampyre · Addict Joined: 12 Oct 2004 Posts: 622 City: Ooltewah, TN

Well, from what I know, a 19 pitch should be ok. I run about the same amount of weight in sacs, and usually with about 400 lbs of people as well.

I personally don't worry about losing 5-7 mph in top end for a better hole shot.

I would look around for a prop shop, even online, and ask them, based on your boat, engine, weight, etc.
Report what you find Very Happy

Rinker04 · Newbie Joined: 29 Mar 2005 Posts: 17 City: Orland Park

Check out www.hillmarine.com. They make custom & stock props. You can get a 4 blade stainless for $269, A five blade runs $329.

I bought a 4 blade stainless from them last year to replace the factory 3 blade aluminum. Made a big difference in pull. Also holds speed a little easier.

lofosho_97 · Outlaw Joined: 05 Aug 2005 Posts: 180 City: lexington

what pitch did you have before and after you changed your prop?

gene3x · Addict Joined: 31 Aug 2004 Posts: 759 City: Dallas

I went down to a 4 blade aluminum and it worked great on my old 5.7L Four Winns. Of course I was running a 16 degree pitch.

Rinker04 · Newbie Joined: 29 Mar 2005 Posts: 17 City: Orland Park

They (Hill Marine) actually recommend a pitch for pitch change. I was running a 21P 3-blade aluminum & stayed with a 21P when I bought the Stainless 4-blade. It definitely helped the hole shot - I'm sure a 5-blade would be even better. Personally, I'd go for more blades & less change in pitch - goto 4 or 5 blades & maybe drop down to a 21P. Hill Marine will "exchange" for a different prop for a $35 fee & any difference in price.