|
1973 13' Pitching Up
|
| azrider26 |
Posted on 07/15/12 - 12:59 PM
|
Member
Posts: 14
Comments:
0
Joined: 07/15/12
|
Hello! Getting 28 mph @ 5500 with my healthy and properly trimmed Suzuki DF 40. Motor is rated at 5200-5800 wot. The prop it came with is 11 5/8 x 12 and I'm at 6200 WOT with this set up. Thinking of pitching up to 15 to bring it down to 5600ish, or 14 for 5800 and get the 35-40 mph I'm hearing about. Which one, 14 or 15? What should the diameter be? In 15 and 14 pitch there is everything from 10-11.5 available. Any insight is much appreciated.
Edited by azrider26 on 07/15/12 - 1:00 PM |
| |
|
|
| Joe Kriz |
Posted on 07/15/12 - 1:14 PM
|
Site Owner
Personal Page
Personal Album
Photo Albums
Project Albums
Posts: 11447
Comments:
452
Joined: 03/18/05
|
The diameter is a given and selected by the engineer.
We can only choose brand/model of prop for our particular motor and then the pitch size.
See this article:
http://www.whalercentral.com/articles...cle_id=108
So, forget about diameter as this is already figured out for us.
What brand/model of 12" pitch prop do you have now?
Edited by Joe Kriz on 07/15/12 - 1:17 PM |
| |
|
|
| Joe Kriz |
Posted on 07/15/12 - 1:31 PM
|
Site Owner
Personal Page
Personal Album
Photo Albums
Project Albums
Posts: 11447
Comments:
452
Joined: 03/18/05
|
If you actually have a 1973 model, then you should have a 20" Long shaft motor and the straight transom with Desert Tan interior.
See this Frequently Asked Question:
http://www.whalercentral.com/viewpage...age_id=155
Other things to check is your engine height.
What holes are the engine bracket bolts in?
http://www.whalercentral.com/articles...cle_id=106
|
| |
|
|
| azrider26 |
Posted on 07/15/12 - 1:48 PM
|
Member
Posts: 14
Comments:
0
Joined: 07/15/12
|
Right on. It's a 73 for sure same as in your link. It's a 20inch and the gear is 2.26 I believe. As far as the diameter that's what I thought too but shopping for props by motor I'm finding everything from 10-11.5. Hmm. That is for different brands though, so maybe that's part of the design for that particular prop? The prop on it does not give a brand but I'm pretty sure it's stock as the motor had under ten hours when I got it, and it showed. I'm looking for max speed as the fishing spots I love are 10 miles away plus. Getting out of the hole fast is fun but I'm not that worried about it.
|
| |
|
|
| Joe Kriz |
Posted on 07/15/12 - 1:51 PM
|
Site Owner
Personal Page
Personal Album
Photo Albums
Project Albums
Posts: 11447
Comments:
452
Joined: 03/18/05
|
I'm finding everything from 10-11.5. Hmm.
Not in the same brand/model of prop you aren't......
If you do see this, please give us a link.
Every brand/model is made differently and has different engineers designing the prop for a particular motor.
Choose one brand/model for your motor....
Like the article says, you won't have a choice in diameter...
Here is what you will see if you choose the "Viper" brand/model for 40hp to 130hp E-Tec....
763929 ViperTM 3 blade 13 7/8" x 15 pitch
763930 ViperTM 3 blade 13 7/8" x 17 pitch
763931 ViperTM 3 blade 13 7/8" x 19 pitch
763932 ViperTM 3 blade 13 7/8" x 21 pitch
Again, we have no choice in diameter..... Only the pitch.....
Edited by Joe Kriz on 07/15/12 - 1:54 PM |
| |
|
|
| azrider26 |
Posted on 07/15/12 - 3:14 PM
|
Member
Posts: 14
Comments:
0
Joined: 07/15/12
|
I haven't seen a single brand with a choice in diameter like you're saying. That said, when I go up in pitch should I pick a brand that has close to the same 11 5/8 diameter or not worry about it. If I go stainless it's a bit of money to gamble as it's seems there's a quite a difference between 10-11.5. Probably more important for me
is 14 or 15 pitch.
Thanks for the quick replies and nice site by the way
|
| |
|
|
| Tom W Clark |
Posted on 07/15/12 - 3:29 PM
|
Member
Personal Page
Posts: 4280
Comments:
7
Joined: 09/30/05
|
On of the ways you decide what model of propeller to use is to see what its diameter is. Diameter is one part of the overall composition of a propeller.
A Suzuki DF40 is not going to have a lot of choices. It uses a 3-1/2" (small) hub.
Let's consider the options. The Suzuki propeller catalog only offers two models of propellers for the DF40, an aluminum three blade in pitches from 7" to 17" and a stainless steel three blade in pitches form 12" to 17". That's it. You don't want an aluminum prop if you are concerned about your boat's performance or else you wouldn't have started this thread.
If the prop you have now is a Suzuki prop and it's 11-5/8" x 12" then it the aluminum three blade, part #58100-88L31-019. I suggest upgrading to stainless steel to help solve your problem.
So that leaves their thee blade stainless steel prop (*if* you want a Suzuki branded propeller) and all you have to do is decide the right pitch. If a Sport 13 can do 35-38 MPh with 40 HP and the DF40 uses a 2.27:1 gear ratio and has a 5800 RPM redline then you will want at least a 15" pitch prop. The Suzuki three blade stainless steel model would then be their 11-3/4" x 15", part #990C0-00501-15P
I actually think you would do better controlling the bow rise by using a prop with better stern lift qualities, and a large diameter prop with less rake will help accomplish that. The Stiletto Star 3.5 is one such prop and you can get a 12" x 15" version with a C-011 hub kit to fit your DF40. It will cost considerably less than the Suzuki branded stainless steel propeller too.
|
| |
|
|
| Joe Kriz |
Posted on 07/15/12 - 3:41 PM
|
Site Owner
Personal Page
Personal Album
Photo Albums
Project Albums
Posts: 11447
Comments:
452
Joined: 03/18/05
|
OK. So you do have an aluminum prop....
I would suggest a SS definitely.
Many prop shops will loan you a brand/model of prop to try out in different pitch sizes before buying....
It's been too long since I owned a 13' so I do not know the best brand/model.
Tom, and others here that have 13' models, might be able to recommend the correct brand/model and pitch for you.
The engineers of the prop calculate the Rake, Cup, and Diameter for a certain motor(s) so basically the only choice we have in that brand/model of prop is Pitch.....
If you take a look at that article again, each 2" pitch change can raise or lower the WOT RPM by about 200 RPM.
If you were to stay with the same brand/model you have now, then you would want more of a pitch.
You don't mention the year of your Suzuki DF40
Here is a chart for Suzuki propellers.
http://www.suzukimarine.com/~/media/M...s_PDF.ashx
NOTE: the SS props for a DF40, 1999 to present
They all have the same diameter of 11 3/4 inches but that isn't always the case. Sometimes the diameter varies but again, we have no choice in diameter in a particular brand/model...
Stainless Steel 11-3/4 x 12
Stainless Steel 11-3/4 x 13
Stainless Steel 11-3/4 x 14
Stainless Steel 11-3/4 x 15
Stainless Steel 11-3/4 x 16
Stainless Steel 11-3/4 x 17
|
| |
|
|
| azrider26 |
Posted on 07/16/12 - 10:31 AM
|
Member
Posts: 14
Comments:
0
Joined: 07/15/12
|
Rock on. Thanks for the time. Being Monday I'll get on the horn with some prop guys, I live two hours from most but no biggy. The Stilleto Star says designed for pontoons, I assume mostly because of the diameter amongst other things but you think that may be a good one. I was looking also at the Stilleto Triad with a 10 3/4 as I don't think I'm having much problem with slip with the big motor and all. I also have a small Doyle fin on there and with that don't get any bow rise or porposing, although I know it's a cover up so maybe your suggestion is a good one the 12/15 Star Tom. No go on the Suzuki SS, out of my price range, although seems like a no brainer. I'll make some calls and check back. much thanks
|
| |
|
|
| Tom W Clark |
Posted on 07/16/12 - 10:42 AM
|
Member
Personal Page
Posts: 4280
Comments:
7
Joined: 09/30/05
|
Yes, the Star is nominally a pontoon boat propeller except it also works on other types of boats too. Here is what the manufacturer wrote about the Star's sibling, the Yamaha branded Pontoon Performance Series version:
Yamaha’s new F70 outboard is finding a home on many new applications, including smaller, lightweight flats boats. While preparing for a recent Press Event, we equipped a 17-foot flats boat with a 13” Yamaha Pontoon Performance Series. It performed flawlessly. People driving the rig could not believe that a three-blade propeller performed very similar to a four-blade, which is the norm for these type platforms, and it did so across the entire range of performance, from hole shot to top-end. That’s because the Pontoon Performance Series (and its sister propeller, the Turbo Pontoon 1), use very large ears with a low rake angle, making them easier to spin up; yet grabbing a large amount of water for maximum ‘traction’. This makes the all-important hole shot possible on these rigs, yet also provides outstanding running performance. Keep this in mind for similar applications, as Yamaha offers these series of propellers to fit most makes of outboards. Now that’s a propeller solution.
|
| |
|
|
| azrider26 |
Posted on 07/17/12 - 12:12 AM
|
Member
Posts: 14
Comments:
0
Joined: 07/15/12
|
Called a couple prop shops today and got some decent but kind of generic info. Actually one person tried to tell me I needed a smaller pitch to get the rpms down. Going on to the beach for a few days in San Diego. May swing by a shop there. Thanks for the info again. I'll check back when in a few to follow up. Cheers
|
| |
|
|
| Tom W Clark |
Posted on 07/17/12 - 5:34 AM
|
Member
Personal Page
Posts: 4280
Comments:
7
Joined: 09/30/05
|
Feel fee to keep talking to "shops" but you've already found the world's best source of prop information for Whalers right here.
|
| |
|
|
| tedious |
Posted on 07/17/12 - 7:31 AM
|
Member
Personal Page
Posts: 1072
Comments:
2
Joined: 09/07/08
|
AZ, you're going to get "a range" of advice from shops, for sure. But don't buy a prop at a shop unless you like spending extra money. The Star 1 + hubkit can be found online for approximately $235 delivered to your door.
Tim
|
| |
|
|
| tigermc |
Posted on 07/25/12 - 10:44 AM
|
Member
Posts: 23
Comments:
0
Joined: 09/20/10
|
I am running a 15 pitch prop on a 73 13 sport with a 40hp Yamaha. I get 38 mph when trimmed out. the best cruising speed with this prop is 28-30mph anything over about 32 mph is not fun.
|
| |
|
|
| azrider26 |
Posted on 07/25/12 - 11:29 AM
|
Member
Posts: 14
Comments:
0
Joined: 07/15/12
|
Back from vacation. I manage a fleet of inspected vessels, I know how hard it is to get really good service, that's why I'm here for sure. Unless its a computer or cracking motors we do it ALL in house. I'm a jetpump guy and sailor so props aren't my game..yet. Tirermc, I know your yammy is different, but what model prop are you running(great motor by the way)? After doing my own research as well, almost ready to go for Tom's suggestion of the Star 1. Less rake, larger diameter= good for my set up. Question-Since I have alum now and my calculation says to go to 15 pitch, so would switching over to the stainless Star necessitate an adjustment in pitch because of the change in material? Also does anyone have any account of this prop being used on a 13 whaler? Also for giggles I just raised the motor up one hole to it's highest(VP 3/4" above keel line) and lost 3 mph and it seems to have slightly more bow rise.
Edited by azrider26 on 07/25/12 - 11:50 AM |
| |
|
|
| azrider26 |
Posted on 07/25/12 - 11:58 AM
|
Member
Posts: 14
Comments:
0
Joined: 07/15/12
|
Another question on the Star. I read it has a fair amount of cup. My current prop seems to have little to none. Since, from what I'm reading, cup can have a similar effect as increasing pitch. For this reason would it change my pitch calculation from 15? Tell me if I'm splitting hairs. Thanks again!
|
| |
|
|
| butchdavis |
Posted on 07/26/12 - 6:38 AM
|
Member
Posts: 838
Comments:
0
Joined: 11/22/11
|
Rider,
I highly recommend you save yourself a lot of time and money and buy the propeller recommended by Tom Clark. Tom sells propellers, too, and his prices are more than reasonable.
Butch |
| |
|
|
| tmann45 |
Posted on 07/26/12 - 11:05 AM
|
Member
Posts: 196
Comments:
0
Joined: 02/18/07
|
Joe Kriz wrote:
I'm finding everything from 10-11.5. Hmm.
Not in the same brand/model of prop you aren't......
If you do see this, please give us a link.
.....
I might be misunderstanding your statement, but Prop Tech has a few models with different diameters. I only looked in the 40-70 HP range since I'm looking for a new one. See: http://www.ptprop.com/images/stories/...cclass.pdf and look for the following models: NREB3, OLC3, SRG3, they all vary diameter with pitch within that model.
|
| |
|
|
| Joe Kriz |
Posted on 07/26/12 - 12:13 PM
|
Site Owner
Personal Page
Personal Album
Photo Albums
Project Albums
Posts: 11447
Comments:
452
Joined: 03/18/05
|
tmann45,
You need to look up the prop for your motor, then give us the props that show up.
That chart shows all the props they have. They all will not fit your motor.
Here is what you find when you look up a SS prop for a DF40, 1999 to present on the Suzuki site.
They all have the same diameter of 11 3/4 inches but that isn't always the case. Sometimes the diameter varies but again, we have no choice in diameter in a particular brand/model...
Stainless Steel 11-3/4 x 12
Stainless Steel 11-3/4 x 13
Stainless Steel 11-3/4 x 14
Stainless Steel 11-3/4 x 15
Stainless Steel 11-3/4 x 16
Stainless Steel 11-3/4 x 17
In other words, pick a brand/model of prop.
Look up what prop fits your motor.
Then give us that information.
I guarantee you that you will not be able to choose anything like this in the same brand/model prop for your motor:
11x17
11 1/4 x 17
11 1/2 x 17
11 3/4 x 17
etc.
Generally you will only be able choose the pitch for your motor in one brand/model prop.
Did you look further on that site above where you gave us the link?
If you had, then you would have seen they Do Not ask you anything about the diameter when asking you about your current prop. They only ask you about the pitch, number of blades and brand of prop of course.
http://www.ptprop.com/index.php?optio...;Itemid=60
The above is the exact same thing they would ask you in a good prop shop.
What motor you have, what brand/model of prop you think you want, and what pitch.
They might give you suggestions on brand/model and pitch for your particular boat and how you use it, but they won't ask you what diameter you want.
Custom Race props are not in the above category. You can have anything you want made to get the most out of your race engine and race boat hull.
Edited by Joe Kriz on 07/26/12 - 12:23 PM |
| |
|
|
| tmann45 |
Posted on 07/26/12 - 5:14 PM
|
Member
Posts: 196
Comments:
0
Joined: 02/18/07
|
Joe, you have me confused with the another poster. I was only replying to your request for a link that shows a certain model prop that comes in different diameters.
|
| |
|
