Parker hull/prop database

[Will W]

I just tried the 15 3/8 x 18 Mirage plus in fresh water it didnt work for me. Ran it for about a hour so If anyone would like to buy a one hour use prop. [email protected] 8287791997

 

[Marty D]

Jim -wanted to know what hole position is that motor ? What you did, testing those prop. was very helpful to all of us.
Thank you
Marty D.

 

[grouperjim]

Jim -wanted to know what hole position is that motor ?

Thank you
Marty D.

It is bolted in the top hole, deepest position. This is how it came from the factory. Tried raising the engine one hole. This resulted in a ventilated prop in certain following seas, so it I moved back to the top hole........no ventilation. It has been my experience that engines set back on a bracket require a deeper running position for the A/V plate than a non-bracketed boat due to the natural variability/turbulence that occurs between the motor foot and the stern which is a couple of feet fwd.

I will also add that another factor that affects my hole position is that my boat rides more level in the water than a factory hull due to using larger trim tabs (12x20w), and a permatrim which lifts the stern of the boat making up for the loss of hull-planing surface due to engine set back on a bracket. I also load the majority of weight on my boat amidship and further fwd for a better CG. The only thing that rides in the transom are buckets of bait/chum and other lightweight items. I also run with 100+ # of ground tackle in the anchor locker which includes 35 ft of chain, 22# delta anchor, 400ft 1/2 line, and a windlass. Running level gives the boat a better ride in the rough stuff, and improved handling.

Go here to see the boat running on plane 18-20mph in a verified 2-4 with and occasional 5 footer jumping up.

http://www.youtube.com/watch?v=fi768KVNa-U

 

[SBH2OMan]

Hey guys, I have another thread of my own going about my current prop issues, but I wanted to make a suggestion for this thread, since it is intended to be a "database" of sorts.

As we all know, posting a single number for MPH, GPH, and SOG can be pretty misleading - the numbers tend to jump around a lot, and single numbers don't really tell the whole story. What I'd find incredibly useful is to see other's performance numbers laid out in chart form (or just PM me the numbers and I'll create the charts for you). To collect the data, I run around looking at the gauges while my "assistant" writes numbers down on a clipboard. What I end up with is a sheet that looks like this:
RPM MPH GPH
3800 12.9 13
4300 18.1 16
4400 25.0 15

And so on with at least 50 or 60 data points at various RPMS. I make it a point to collect a bunch of data (even at the same rpm) because it helps create a good scatterplot diagram where you can begin to see a "picture" of the performance like these:

(yes, I have a terrible problem with my prop slipping, I know - and I can't figure out why). What I'd love to see is more data on prop slippage from other 2320 owners (with bracket-mounted motors) to see how far I am from the "mean". It would also be very interesting to see what sort of difference (in terms of empirical data) the Rev 4 makes versus the Mirage Plus. Anecdotal evidence is great ("handles much better!") but I'm a data hound...

By the way, the prop slippage can be calculated with the following formula:
(((pitch x RPM)/(gear ratio x 1056))-mph)/((pitch x rpm)/(ratio x 1056))

 

[no limit]

1996 2320

Repowered with a Etec 250 transom mount.

With Full Tank and 6 people, and 100 lbs of gea, 47 mph at 5800 WOT

 

[warthog5]

I did a ton of prop testing in `05 and `06. Three blade, four blade, aluminum and stainless...

Right now my motor is wearing a Mercury Mirage Plus (17p) that I bought used. The previous owner had it tweeked with a little more cup, which I really didn't need... but so far it does pretty well.

The 'cruise sweet spot' for my 1997 Yamaha 225 OX66 is 4200 to 4400 rpms (when the Bay chop allows it). At 4400 she is running 27 kts with full fuel and 3 people aboard and burning 13 gph. I think that is pretty good for as much gear as I carry. :shock:

What is the dia. on that prop Kev?

 

[warthog5]

Black Painted Stainless..... I think it is a factory Yamaha Prop. 3 X 14 X 17

'95 2530..... 1/2 full of fuel [75gal] 4 people onboard and no extra weight.

'95 VX 250 Yamaha Carbed 2 stroke.

Maxed out
5400 RPM = 35MPH burning 23.3GPH = 1.6MPG

5000 RPM = 31MPH burning 20.4GPH = 1.6MPG

4600 RPM =27.5MPH burning 14.6GPH = 1.9MPG

4200 RPM = 24MPH burning 12.8GPH = 2.0MPG

4000 RPM =20MPH burning 11.4GPH = 1.8MPG

 

[warthog5]

I raised the motor 2 holes from being all the way down. I didn't get all my data numbers yet. But it brought the RPM up 100 to 150 RPM. It now holds 5500 and bounces on 5600. It does not blow out when turned hard over in a turn.

I still think it needs a prop change.

 

[Megabyte]

It is this one Bobby...

viewtopic.php?p=88126#p88126

 

[warthog5]

We got some new numbers yesterday with a new prop to try.

'95 VX 250 2 stroke. 5 people onboard and tanks full [150gal]

Prop = Powertech 4 X 15 X 15

The boat came out of the hole better.
The prop gave the boat more stern lift and put the cavitation plate where it needed to run.

Top speed was

35.6MPH @ 5500RPM = 23.3GPH - 1.4MPG

28.5MPH @ 4500RPM = 15GPH - 1.9MPG

26.5MPH @ 4200RPM = 13.3 - 1.9MPG

23MPH @ 4000RPM =13.5GPH -1.8MPG


We had problems right after that. I believe there is a lot of trash in the fuel tanks and causing problems. The tanks are fixing to be emptied and cleaned.

Glad that at least the boat got these numbers, as I would have condemned the prop for poor performance.

The dependability can't be trusted in this boat so far.

 

[Megabyte]

Will you use a tank cleaning service, or will you pull them and do it yourself?

 

[warthog5]

I'm not going to pull them or use a service. I'll do it myself.

First we suck all the fuel out and into 5gal cans. I have a buddy that has a LOT of them. It will be run thru a Fuel filter funnel....then into the cans.

Next the tanks will be filled with water and sucked out over and over again.

Then a air will be blown into the tanks under extremely low pressure just to move some air and cause drying.

This is how a buddy of mine did it to another boat with the same problem. Dry Gas was added to the fuel for safe measure.

 

[warthog5]

The numbers I posted above have fallen away. These boats are weight sensitive.

We got the motor running better than ever. It's of my opinion that we just ran out of motor. Boat is full of fuel. 148gal [usable] That is aprox 962lbs

I have a 3 X 15 X 16 to try.

It does me no good to get great mileage and then load the boat down like it was going offshore and it becomes a Pig.

 

[warthog5]

Well it's better, but....nothing to really brag about.

This was a good day to test a boat. It was nasty out White caps all over the bay...wind blowing. Water blown up on the windshield many times. Center consoles should have stayed home. I know I wouldn't do it. But there was 3 out there in the 22ft range.

3 X 15 X 16

Boat full of fuel....[well close enough] 2 adults and 4 kids....[kids added together =225lbs]

The boat on slick water barely would hit 5000RPM.
It still stumbled out of the hole, but not near as bad.

The best was 4000RPM -1.8MPG- 25MPH That was it's average....It did change with the current which was out going tide and moving pretty strong. The MPG dropped as low as 1.4MHG

This seems to be the best prop that we have tried so far, but I'm not satisfied.

It did give me the stern lift again that we lost with the 3 X 14 X 17.

The cavitation plate was even with the surface.......Right where you want it.

This boat differently needs a trim gauge, so I don't have to keep turning my head and looking at the motor.

The 24 X 9 Bennett's had 20% flaps in them for the most part.


I would Love to try a Rev 4 - 14 5/8 or 14 1/2 X 15.

I think the smaller diameter would allow the motor to rev up, but the 4 blade would give the ass end the lift it needs.

All in all we learned some things and had a nice afternoon....The temps are dropping fast now. Supposed to go into the high 20's.

The granddaughters played house while we were dragging some Mann's Stretch 30's for some Redfish. Saw them on the screen, but no bite.

 

[Brent]

Are you considering using 2 props? One for loaded boat and off shore use and another one for daily use?

 

[warthog5]

No.... I just want to find the best happy medium.

When 2 boats that we have for sale get sold a new motor is going on and that will change everything again.

 

[warthog5]

Well I spoke to Ken @ PropGods today. He's sending a Merc Inertia. 3 X 15 X 15

He said it will spin up a little easier.

Oh..and he told me he use to live in Pensacola and his folks still do.

 

[warthog5]

'91 2520 with a '07 300 Suzzy. It's listed on Criegslist for sale.

Anyway My son called him and right up front told him he had no interest in buying the man's boat , but wanted to pick his brain about props and performance.

Seeing how there is a real lack of info for a 300 Suzzy and on a MV hull, I throught it was worthy of adding.

I called the guy and told him I had no interest in buying his boat but did he have a minute....


Bottom line they guy is a more knowledgeable than most boaters. With a heavy load the boat would make 26 knots turning 4400 @ 2.0 mpg. They tried a few different props and have a 3x16x17 on the boat now. The 3x16x21 originally recommended would not let the engine turn up. He said that the suzzy 3x16x17 would only let him make 6,000. The boat was slow to respond with a heavy load and very responsive with a light load. That’s about it other than he was happy with the Suzzy and the boat overall. He did mention the new engine and it's efficiency. He felt we would get 2.5 with the new engine and after playing with props.



http://tampa.craigslist.org/pnl/boa/3639959822.html

 

[grouperjim]

The pitch of a prop can determine several things. One of the main factors is turns per knot which ultimately determines how fast a given hull will do considering an average amount of prop slip. IMO a 21 pitch prop has no business on a MV PH Parker. Regardless of max RPMs a 21 pitch pitch prop with average slip is going to push a hull high 40s low 50s which is counter to the intended use and design of the MV hull.

The best advice is to choose a prop with a pitch that pushes the hull at the desired speed range for the design and purpose of the hull. In the case of a Mod V it will be a 15, 16, or 17 max pitch prop. Increase or decrease the diameter of the prop to adjust for desired WOT RPM. On a fishing boat, I personally prefer the largest diameter prop that will give me WOT RPMs required by the manufacturer for the motor, and a pitch that will give me a decent cruise at 75 percent of the manufacturers suggested max RPM.

In my case a Yamaha motor with a manufacture's suggested max RPM of 6k, my DV hull likes to cruise at 32mph at 4500 rpm which is right at 75 percent of WOT RPM. FWIW to get this I require a 3x15 3/8x18.

Wart, with a 300 Zuke I'm thinking you'll end up with a 3x16x16-17p or similar of the new 4 bladed PTs that Dale has been talking about.

 

[warthog5]

Wart, with a 300 Zuke I'm thinking you'll end up with a 3x16x16-17p or similar of the new 4 bladed PTs that Dale has been talking about.

:mrgreen:

Here's what Ken @ PropGods said.

Dale was running 38-39 MPH with a DF250
5900 RPM at 39 MPH is 24% slip, which is a little higher then I expected it to be on that setup.

You should get a couple mph faster. I'd say 42-43 with a light load judging from Dales numbers.
2.08 gear lets say we get you down around 13% slip shooting for 6100 RPM
A 17 pitch should do well.

If your going with stock suzuki props, the 16X17 would be the only choice.
Powertech, I'd go with the LFS4 in a 17 pitch, and it might need a little extra cup to get it biting better.