Details on prop - MerCruiser 3.0L

[Sn00ky]

Hello everyone,
I am curious as to how I can find out the prop pitch I currently have on my boat...it has a number on the side of it.

Mercury 832834A45P23

Anyone know what this prop may be in terms of pitch/diameter??? Thanks!

I am wanting to change the pitch as to help with getting out of the water for skiing / wake boarding. With 2 people in the boat, it tops out about 4500rpm and 45mph, and takes a short while to get there. When the boat has 5 people in it....and some gear (approx 1000 lbs), I had to get two people up in the bow in order to plain out, and had about 4000 and 38mph, however, I think there was room to go, just ran out of lake and tolerance for the swells.
Overall top speed, I don't need any more than 35mph, but I would like to sacrifice that to gain ability to get the hull out of the water faster.

I am thinking about either one, or all 3 changes, but looking for recommendation to try first before gussing. Any of, dropping pitch, reducing diameter, and increasing blades, are options as I assume to be the 3 main points to a prop, and please correct me if I am wrong.

Again, once the engine is out of the water, she runs strong, but lacks the HP to pull it up quick. And it really feels to me I can improve this just buy changing the prob.

Any advice is appreciated, I know from reading other treads that everyone likes to see results, and I will provide them, however, I probably won't want to buy 4 or 5 props for this....just to test, unless I can find used/good deals. But whatever I do try I am more than happy to supply this tread with results.


Little blurb about the craft...
18' Maxum 1800 MX sportboat
3.0L MerCruiser Alpha - original prop of ??? 3 blade maybe 19p??
Engine running strong - inspected / serviced regularily...
I believe it to be a 2.0 gear ratio, not 100% sure on that


Thanks again everyone!!!

 

[hwsiii]

Re: Details on prop - MerCruiser 3.0L

Snooky, you need to order a 21" pitch Solas Amita Aluminum 4 blade prop to take are of your problems. It will get you up on plane with a heavy load much quicker than you now do, it will plane at lower speeds and you should not lose any top speed as well. It will also raise your RPM by a couple of hundred RPM.

The prop you are using now is a Mercury 14" X 23" pitch prop.

You might try reading this for a better understanding of motor height, changing props for better performance, and for the major differences between aluminum props and stainless steel.

http://forums.iboats.com/showthread.php?t=369057



H

 

[Bayliner175xt]

Re: Details on prop - MerCruiser 3.0L

Hi Snooky, we are using a Piranha 4 Blade prop 13"Dia - 22"Pitch and it works well for us, I have a set of 13-20P blades which we use for Wakeboarding,
Our WOT speed is about 40Mph (speedo)but we never get that high.
I'm about to install a set of SX Smart Tabs, which i have read on here will make a huge difference. I tried a Permatrim Foil and wasn't really happy,

Our Boat is a 2004 Bayliner 175 XT Bowrider (17-1/2 ft) with a 3.0 Mercruiser Alpha 1 drive.
We found moving 1 or 2 people to the front of the boat made a big difference.
Our boat get's onto plain towing a skier in about 2 seconds.
We tried the 14" Dia blades but found the 13"Dia better.
The reason we use the composite blades is we ski in a river or dam area, and have had one strike already, it only cost us 2 Blades ($50 Au) to replace them and 2 minutes time.
The lower leg unit will cost allot more...LOL.

 

[steelespike]

Re: Details on prop - MerCruiser 3.0L

H has a lot of experience with the Solas Amita 4 blade you won't be dissapointed.
I'm surprised you did so well with the 23 that seems like a lot of pitch for a 3.0.

 

[180shabah]

Re: Details on prop - MerCruiser 3.0L

+1 for the amita

Can you believe I didn't suggest the hustler???? He wanted more watersprots performance, so I think the extra blade will be more beneficial here.

 

[hwsiii]

Re: Details on prop - MerCruiser 3.0L

Shabah, LMAO I know you love those TP's.



H

 

[Sn00ky]

Re: Details on prop - MerCruiser 3.0L

Thanks for the help everyone....the advice is much appreciated....
I thought hard about the 4 blade, but then I found a good deal on a 3 blade 19p aluminum....more for a test than anything, got it for 150...which i thought to be a decent price for a new one. I am going to try this out...and seeing as how it's cheaper than I expected, I will be willing to try another as well, so I will probably try the 4 blade recommended above...sounds like you were quite pleased with it.
I have the new 19p on now, but won't try it for another few days...I will let you guys know how I make out...

Thanks again!

 

[180shabah]

Re: Details on prop - MerCruiser 3.0L

So what prop did you get?

Just please tell me you didn't drop $150 on a black max?

Both the amita and the hustler are available right here at iboats for $100 including hubs.

 

[Sn00ky]

Re: Details on prop - MerCruiser 3.0L

It was a 3 blade 14.5x19P vortex...
Hopefully have it out tomorrow....it's fairly cheap so it leaves me $$$ to play with other sizes if need be.
I am up here in Canada ay...haha...so it is probably worth the other 50 to be able to pick it up at a local store....but maybe when I finalize the size I want it may be worth while to order from iboats??? What do you suggest?

 

[180shabah]

Re: Details on prop - MerCruiser 3.0L

Let's bseline what you just put on, before go too much further with suggestions?

let us know how it does.

 

[Sn00ky]

Re: Details on prop - MerCruiser 3.0L

Well, it made a huge difference so far. I was able to plain out even without putting anyone of the 5 people in the bow - something I couldn't do with the 23P
She gets out of the hole much faster....and @ WOT does about 4800RPM @ 43mph, this is with only 2 poeple in the boat and no gear.
Due to weather I couldn't try it with all 5 people because the women were nervous of the swells.
I was told to keep the rpm around 4600 or so for this engine, thou I read that range to be 4400-4800....And after having it opened up, it felt like the engine was over-reving, however, no visual sign of it...just a feeling - you know what i mean!...haha

So at this point, I am very pleased....still open to conversation and ideas thou?

Thanks again everyone!

 

[180shabah]

Re: Details on prop - MerCruiser 3.0L

Sounds about perfect. 10% slip and top of your WOT range, enjoy.

 

[Sn00ky]

Re: Details on prop - MerCruiser 3.0L

Awesome, out again today, and it was just beautiful....running like I said with the numbers above....feels real strong.

What do you mean by 10% slip? I don't understand, thou it sounds like a good thing? Hhaha, thanks!

 

[180shabah]

Re: Details on prop - MerCruiser 3.0L

prop slip?

the pitch stated by the manufacturer is the distance the prop would travel forward for EACH revolution if there was ZERO slip. We are turning them in water, so we will never get 100% efficiency. That slip is as high as 100% (in gear but boat tied off) but we try to minimize it at WOT. Anything under 15% is Good, single digits are ideal, but rare on pleasurecraft.

 

[steelespike]

Re: Details on prop - MerCruiser 3.0L

+1 for the amita

Can you believe I didn't suggest the hustler???? He wanted more watersprots performance, so I think the extra blade will be more beneficial here.

I like the Hustler & Rascal but they just seem a little unpredictable.
I have seen some very good results and others that were dissapointing
for no obvious reason.I'm not expert enough or patient enough to try to do a lot of calculations like some of you guys.Maybe someone could work up a program aimed at the
Hustler/Rascal design.

 

[Sn00ky]

Re: Details on prop - MerCruiser 3.0L

Ahh, the slip makes sense now....well is sounds like 10 is good, so thats awesome!

Like I said before, I am still willing to try different things....would anyone sugggest a 4blade? maybe a 21P or something?

Just wondering, I am content as it is now, however open to try anything!

 

[hwsiii]

Re: Details on prop - MerCruiser 3.0L

Spike, you know I trust the numbers, and I have run the numbers on 9 different Turning Points and 4 weren't even close to what was expected, that is why I never recommend them, the numbers are just too erratic, and they shouldn't be.



H

 

[steelespike]

Re: Details on prop - MerCruiser 3.0L

I wonder if hull form is more critical to them?Any clues?

 

[hwsiii]

Re: Details on prop - MerCruiser 3.0L

Spike, eight of them were modified vee hulls, so I don't think so. In my opinion, I think the blade geometry is very aggressive for a casting using aluminum and not stainless steel, and also NOT using a squeeze casting process for this implementation.

But just remember, I am NEVER wrong, UNLESS I am breathing.



H