4 Blade Recommendations

[TheBlizzard]

Boat: 1989 Celebrity 20' cuddy
Motor: Mercruiser 5.0 200hp
Max RPM: 4200-4600

Current Prop: 14 1/2 x 19P 3 blade (not sure what brand), newly reconditioned.
Current Performance: reaches 4600 RPMs at WOT, 1/2 tank (20gals) fuel = 47-52mph depending on conditions.

Dilemma: With a 1/2 tank of fuel and just a few people in the boat it has no trouble getting up on plane and it has a great top end in my opinion. Loaded down with fuel and people it struggles to get out of the hole; it will get on plane but takes 5 times longer than it does with a minimal load. Also I cannot go below 3000 rpms while on plane or the boat starts to sag and come off plane.

Since the RPMs are dialed in pretty good with the 3 blade 19P I don't want to mess that up by switching props. However I am enticed by the thought of a 4 blade that will help the hole shot and hopefully sustain a plane at a lower RPM than 3000.

So basically what I am asking is what 4 blade will still give me 4600 rpms at WOT. I don't care a ton about top end, since 50mph for this cuddy is plenty for me.

Any suggestions are greatly appreciated.

 

[MarkChambers]

Re: 4 Blade Recommendations

Mercury Rev 4 x 17P -- Probably

You need to go the prop gods forum and ask your question there.

http://www.propgods.com/forum/default.aspx?g=topics&f=1

 

[90stingray]

Re: 4 Blade Recommendations

Since your rpm is good... I would stick with the 19 pitch. do a 4 blade of your preference... stainless or aluminum. If you run more loaded down mostly and are looking for holeshot.... then go with 17 pitch... but watch the revs when empty. I think there are some 18p props out there you could split the difference. You will be happy with the 4 blade for sure.

 

[Bamaman1]

Re: 4 Blade Recommendations

You could probably use a set of trim tabs. Some use Smart Tabs @ $175ish, and they're automatically lower when the boat stops and retract by water pressure. They work, but they're not adjustable.

I spent $475 for Bennett trim tabs, which are controlled by a dash switch hydraulically. You drop them before you start out, and your boat will immediately plane off. Then you push two buttons at once, and the front end raises.

1. It makes the boat accelerate from a stop like you've got 50 more horsepower.
2. If you have two fat women sitting on one side, you can drop one tab and level out your boat.
3. You can cruise at very slow speeds (8-10 mph) with the nose down.
4. You can drop the nose immediately if you come up on a big wave--plow through the wave and then raise the nose of the boat back to cruising level.
5. They make your boat ride like it's 3' longer--especially in big waves.

Trim tabs are very easy to install, and it's the best money I ever spent.

 

[ramster]

Re: 4 Blade Recommendations

Seems like your revs are good, so I would try a 14X18 four blade. Typically you drop an inch of pitch when switching to a four blade, this a general rule of thumb it does not alway work out that way depending on the prop. Smart Tabs work great, they are cheap and easy to install and, automatic so you don't have to fiddle around with them. A system like the Bennet tabs will give you ultimate range of adjustment while running. It really depends on where you do most of your boating, smaller boats on smaller lakes go with the Smart Tabs, on bigger water cruising longer distance go with the Bennet's.

 

[elkhunter338]

Re: 4 Blade Recommendations

I like my 4 blade pro-pulse prop. You can adjust the pitch and fine tune the top end rpms.
Manual adjustment with the boat out of the water.
Max hp is 300hp, you are well below that.

 

[Leardriver]

Re: 4 Blade Recommendations

A Solas Amita 4 blade in 18 pitch is around $100 on this site. They work great and it's tough to beat the price.

 

[TheBlizzard]

Re: 4 Blade Recommendations

Thanks for the responses (love the 2 fat women comment, so true). I think I might try the 18p 4 blade, I think going to a 17p would be too much as even with a load I spin the 19p 3 blade to 4600RPMs. I have thought of smart tabs and even a full trim tab set, but I don't think this boat needs it at this point even though the nose down effect for big waves entices me. I think I am going to get a 18p 4 blade and try it out and see what happens.

 

[Howard Sterndrive]

Re: 4 Blade Recommendations

sounds like smarttabs might be a better investment than a prop

 

[Mike Zee]

Re: 4 Blade Recommendations

Hey Blizzard i have a 1989 Celebrity 231 SE 5.7 260HP, I'm running a 14 1/4 x 19 4 blade. I love it, pulls 4 kids on a tube like they ain't even there! Dont know the speed but holds plane at 2600 RPM. The boat feels like its bairly moving. I love the thrust at 2600 rpm, when I nail the throttle. To do it over, i would have done it 10 years ago. Perhaps i would like to try a 14x18 or a 14x17 just because may be better at wot rpm's. I'm at the very low end of my motors potential. I would rather be at the upper end, just because. The low speed maneuvering around the dock is great too.

 

[TheBlizzard]

Re: 4 Blade Recommendations

Hey Blizzard i have a 1989 Celebrity 231 SE 5.7 260HP, I'm running a 14 1/4 x 19 4 blade. I love it, pulls 4 kids on a tube like they ain't even there! Dont know the speed but holds plane at 2600 RPM. The boat feels like its bairly moving. I love the thrust at 2600 rpm, when I nail the throttle. To do it over, i would have done it 10 years ago. Perhaps i would like to try a 14x18 or a 14x17 just because may be better at wot rpm's. I'm at the very low end of my motors potential. I would rather be at the upper end, just because. The low speed maneuvering around the dock is great too.

What RPMs are you turning at WOT out of curiosity. Yeah a 231 SE is a way bigger/heavier boat, but should be comprable considering you have 60 more hp than I do.

 

[Mike Zee]

Re: 4 Blade Recommendations

4300 rpm down from 4900 with the 3 blade stainless 13x17. The 13x17 was a spare i had from another boat. i put it on after chewing up the 14x19 3 blade. I would love to get it to the 46-4700 rpm range. But i am really happy with the results. I know before the end of the season i will hang a 14x18 4 blade on. I think you would be spot on with the 14x18. One more thing, i cant believe how smooth the boat is running. Took it on an 18 mile run, about 3000 rpm, towing 4 kids on a tube, steering rock solid straight as an arrow, it was an absolute pleasure. I have owned this boat for several years, it's like a new boat! The kids are older and into watersports so everyone loves it now.

 

[Mike Zee]

Re: 4 Blade Recommendations

I just reread your first post, dude get the 14x18 (17) 4 blade and never look back! Seriously, it's what your looking for. I got one from this site on sale for like 80 bucks. The solas, not too bad for the money. I think either size will do you good, i'm still thinking 14x18 would be for you.

 

[Tail_Gunner]

Re: 4 Blade Recommendations

No prop will give you the lift Nauticus trim tabs can deliever..... and that is what you need in this application....Even when there on you, probably would need a prop with less pitch if you want to run with a load of people and maintain good gearing for heavy loads.

Hmm some opinion huh..

 

[whitecrystal1]

Re: 4 Blade Recommendations

You could probably use a set of trim tabs. Some use Smart Tabs @ $175ish, and they're automatically lower when the boat stops and retract by water pressure. They work, but they're not adjustable.

I spent $475 for Bennett trim tabs, which are controlled by a dash switch hydraulically. You drop them before you start out, and your boat will immediately plane off. Then you push two buttons at once, and the front end raises.

1. It makes the boat accelerate from a stop like you've got 50 more horsepower.
2. If you have two fat women sitting on one side, you can drop one tab and level out your boat.
3. You can cruise at very slow speeds (8-10 mph) with the nose down.
4. You can drop the nose immediately if you come up on a big wave--plow through the wave and then raise the nose of the boat back to cruising level.
5. They make your boat ride like it's 3' longer--especially in big waves.

Trim tabs are very easy to install, and it's the best money I ever spent.

X2 There is a lot of benefit from tabs

 

[MarkChambers]

Re: 4 Blade Recommendations

Tail_Gunner is right. Put the smart tabs on and then play with props. I'll never have another boat without them. I spent several weeks testing and comparing first a three blade 14 1/2 x 19 aluminum (stock prop on the Volvo 5.7 Gi on my boat) with a 15 1/2 x 19 Mirage Plus and then the Mirage with a 14 3/4 x 17 Rev 4. With the 19 aluminum my top speed was 51.8 @ 5000 RPM and with the Mirage Plus it is 53.9 @ 4850. With the Rev 4 my top speed is 51.5 @ 5025. Gearing on my boat is 1.51. You can read the whole thing at the following link. It might be helpful.

http://www.propgods.com/forum/default.aspx?g=posts&t=841

 

[TheBlizzard]

Re: 4 Blade Recommendations

Tail_Gunner is right. Put the smart tabs on and then play with props. I'll never have another boat without them. I spent several weeks testing and comparing first a three blade 14 1/2 x 19 aluminum (stock prop on the Volvo 5.7 Gi on my boat) with a 15 1/2 x 19 Mirage Plus and then the Mirage with a 14 3/4 x 17 Rev 4. With the 19 aluminum my top speed was 51.8 @ 5000 RPM and with the Mirage Plus it is 53.9 @ 4850. With the Rev 4 my top speed is 51.5 @ 5025. Gearing on my boat is 1.51. You can read the whole thing at the following link. It might be helpful.

http://www.propgods.com/forum/default.aspx?g=posts&t=841

Interesting thread on propgods.

On a different note; now I don't know what to do, there are different opinions that all sound plausible and great ideas. I should add that with my drive all the way down it drives the nose of the boat down and cuts waves excellent, I don't have a bow down issue, even though Im sure smart tabs to make it even better. The dilema I have is that smart tabs are $100-$200 (at least thats the price I found) and a decent prop is in the same range, now Im like "WHAT SHOUld I DO".

 

[Tig]

Re: 4 Blade Recommendations

My boat had the same full load issue as you are trying to address. After much thought, I recently went from a generic 14p 3 blade aluminum prop wot @ 6300 rpm to a 12p 4 blade solas Amita wot @ 5600 rpm. I was really hoping to stay closer to redline @ 6000 rpm. Max load performance did not change noticably. I probably should have dropped to an 11p, or perhaps stayed with a 3 blade. It's very hard to predict the change. Finding a prop shop with an exchange program is the best way to make drastic changes.

 

[Tail_Gunner]

Re: 4 Blade Recommendations

Interesting thread on propgods.

On a different note; now I don't know what to do, there are different opinions that all sound plausible and great ideas. I should add that with my drive all the way down it drives the nose of the boat down and cuts waves excellent, I don't have a bow down issue, even though Im sure smart tabs to make it even better. The dilema I have is that smart tabs are $100-$200 (at least thats the price I found) and a decent prop is in the same range, now Im like "WHAT SHOUld I DO".

The tabs will answer a lot of your questions....You may not need a prop and tabs here at iboats should be 125-150

 

[TheBlizzard]

Re: 4 Blade Recommendations

The tabs will answer a lot of your questions....You may not need a prop and tabs here at iboats should be 125-150

But with the smart tabs am I still going to be able to get the bow up with the trim or are they going to want to hold it down? I like being able to get the nose out of the water with the drive for obvious reasons.