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2011laramie
07-27-2016, 03:14 AM
Just seeing what guys are running on their aluminum boats. I got a new fishhawk 1750 with a 115 merc. it has a 4 blade 12.5x19p prop and i think i wanna go down a few degrees to slow the troll speed. i dont need the top end speed.

2011laramie
07-27-2016, 05:13 AM
i see on the mercury website under the test boats, they used a 1750 fishhawk with a spitfire 4 blade prop, 13.4x15p

Okotokian
07-27-2016, 10:37 AM
Just seeing what guys are running on their aluminum boats. I got a new fishhawk 1750 with a 115 merc. it has a 4 blade 12.5x19p prop and i think i wanna go down a few degrees to slow the troll speed. i dont need the top end speed.


I have a setup very similar to yours. 17.5' Princecraft aluminum with a 115 hp Mercury Optimax. I have a 4 blade 17" pitch prop on her and a 3 blade 17" pitch as a spare. I've been thinking of dropping to a 15" pitch, not for trolling, but for a better hole shot. Like you, I'm less concerned about top end speed.

One thing you want to check is what your max RPM range is in your engine manual, and then test out on the water to see what your engine is running at when you are at full speed. If you are already at the top of your approved RPM range, gong down in pitch will put you over it. (No expert here, I just learned all this recently). My range is 5000 to 5800 rpm. At full throttle I'm doing about 5300 rpm, so I have room to go down in pitch a bit.

All that said, I don't use my 115 for trolling. I have a 15 hp "kicker" motor as well and also an electric trolling motor (which I haven't even used yet). I like the kicker for trolling. It's much smoother, quieter, and frankly, I sort of like the idea o having backup if my main engine ever kicks the bucket someplace I want to get home from. I'd recommend you look into a separate trolling motor, gas or electric, if you think you are going to be doing a lot of it.

If you want to explore props a little more, Turning Point propellers has a great "Prop Wizard" where you feed in al the data about your boat, engine, etc. and the program suggests props. You will need to know all your boat and engine dimensions including the RPM range I spoke of. You can even get their customer service guys to advise you by email after you have run the program.
https://turningpointpropellers.com/

good luck!

neilsledder
07-27-2016, 01:12 PM
So Kegriver what pitch of prop is on your boat??? Ever think to ask a situation before jumping to conclusions about what someone can afford or not.



As my post a few weeks ago the electric trolling motor footpedal acted up and i was forced to used my main 115 as a trolling motor for the weekend. The foot pedal issue is now resolved. I plan on using the electric more for the rest of this summer and then deciding if i want to upgrade to the ipilot or leave the minn kota as is and get a small 9.9 kicker over winter.



Another option that would be easy to try is a drift sock to slow it down some.


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jim summit
07-27-2016, 02:00 PM
A simple temperary fix is a 5 gallon bucket and some rope. Toss it behind the boat... Going down coupe inches in pitch will make a small difference in trolling.
Till you can get the troller fixed.

2011laramie
07-27-2016, 06:31 PM
25" xl leg high thrust kickers are not cheap. yamaha are upwards of 6g installed with all the options, the merc is 3600 for the motor alone. honda is 4100. And apparently the efi suzuki isnt available in Canada according to the one dealer.

The biggest reason i was inquiring about props is because my boat will not hit top end rpm. seems to only hit 4800 instead of mid 5's.

but what does it matter if someone you dont know wants to spend 210 dollars on a 2nd prop to make their time on the water more enjoyable.

EZM
07-27-2016, 09:38 PM
XL (25") is not what you need on that boat - it will plow and slow you, reduce your ability control the boat, etc.. These are for sailboats or very deep (high) boats.

Almost ALL fishing or ski boats require a 20" - the same as the main engine.

Walleyedude
07-28-2016, 07:12 AM
Based on the limited info you've given, I would suggest that a 19P prop is too much for your boat/motor combination.

I would suggest selecting a prop based on optimum performance, ie. a prop that gives you the characteristics you want, whether that's hole shot, top speed, handling, lift, etc... while being within the manufacturers suggested RPM range at WOT. A 17P or even 15P will likely give you better all around performance.

Unfortunately, you likely won't find a significant difference in trolling speed by dropping 2-4" of pitch.

As for a kicker, the dedicated high thrust kicker motors with electric start and power trim/tilt are really nice, but any small tiller handle four stroke will work just fine. Most 17-21' ft fishing boats including your Crestliner Fishhawk 1750 actually require a 25" shaft for the main outboard, but you want the 20" shaft for a kicker, the 25" will be far too long and drag in the water when tilted up, especially on take off.

neilsledder
07-28-2016, 07:30 AM
25" xl leg high thrust kickers are not cheap. yamaha are upwards of 6g installed with all the options, the merc is 3600 for the motor alone. honda is 4100. And apparently the efi suzuki isnt available in Canada according to the one dealer.



The biggest reason i was inquiring about props is because my boat will not hit top end rpm. seems to only hit 4800 instead of mid 5's.



but what does it matter if someone you dont know wants to spend 210 dollars on a 2nd prop to make their time on the water more enjoyable.



If your not hitting top rpms and you put a lower pitch on to get your top rpms, you might even gain some speed!


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SamSteele
07-28-2016, 08:15 AM
Just seeing what guys are running on their aluminum boats. I got a new fishhawk 1750 with a 115 merc. it has a 4 blade 12.5x19p prop and i think i wanna go down a few degrees to slow the troll speed. i dont need the top end speed.



Most dealers have a prop "try and buy" program where you put a deposit down and commit to buying a prop. They then let you try out a number of different props to see which one works best for what you need. Bring back the ones you don't like (undamaged of course) and keep the one you like best.

Saves a lot of guessing on what will work and what won't. You may pay more for a prop than you will from somewhere like eBay or Amazon, but it will be the one you want.

SS


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2011laramie
07-29-2016, 01:02 AM
http://i1293.photobucket.com/albums/b584/08arcticcat/Mobile%20Uploads/20160728_202808_zpsmj30lxwq.jpg (http://s1293.photobucket.com/user/08arcticcat/media/Mobile%20Uploads/20160728_202808_zpsmj30lxwq.jpg.html)


http://i1293.photobucket.com/albums/b584/08arcticcat/Mobile%20Uploads/20160728_202852_zpsdhpeqcnu.jpg (http://s1293.photobucket.com/user/08arcticcat/media/Mobile%20Uploads/20160728_202852_zpsdhpeqcnu.jpg.html)

I was assuming i needed a 25" leg cause that's what the dealer mentioned, and after i measured it, it made sense to have the prop below the bottom of the transom.

Walleyedude
07-29-2016, 07:17 AM
Hmmm. With that raised transom you just might need a 25" kicker.

The majority of boats do use a 20" kicker, that's the standard. I know the 25" kicker can be a problem because I had one on a Lund Pro V, and it was too long, it would drag in the water at any speed below a flat plane.

EZM
07-29-2016, 11:22 PM
I wouldn't mount a kicker onto a raised transom.

The fact that your dealer suggested it seems strange to me. That raised transom looks like it is not level, and the flange is likely unsupported in that place. I know it's only a 9.9 that weighs like 100lbs - but you are still bouncing down a road and twisting and bending that flange.

Maybe I'm overthinking it. Maybe it's not a big deal.

I could be wrong but it seems strange they would not design the transom to accommodate the common 20" kicker.

20" kickers are the norm for 9.9's, and have various options like power trim, tilt, remote steer, tiller, electric start, pull start in almost any combination you desire from most manufacturers - you won't find these options and flexibility as readily available with most 25" kickers at 9.9 hp.

Bigger fishing boats - that require a 25" leg often run a 15 or 20 hp (where these options and combinations are readily available as well).

A 25" 9.9 is almost always a sailboat kicker.

Either way - that's what you are dealing with .......... so ..........

My dealer, who I know understand boats likely would have recommend the installation of a jack plate in your application. That's probably what I'd look at doing if I were in your place.

Big Sky
07-30-2016, 10:43 AM
No front electric on your boat?
So, so quiet for trolling. I've got a MinnKota powerdrive with I-pilot. The 70lb, 24volt will pull your 1750 around with no problem. Best feature by far is the 'anchor' that holds you in place. When I first used the anchor, I could not believe what a convenient feature it is.

As far as mounting a kicker on your transom, I say why not. I had a boat with a similar transom and I had a kicker mounted on it for over a decade. Zero issues.

The Crestliner website shows a 9.9 kicker as an option for your boat, so I'm sure it'll be ok. Evinrude, Merc and Tohatsu make some smaller sail outboards in the 5-6 hp range that have 25 inch shafts if you want to keep the weight down.

Sail outboards have a few features that make them appealing.
25 inch shaft.
Some will have a small alternator.
Sail outboards can be run in reverse at high thrust without the prop coming out of the water.

And congrats on the new boat!! Those 1750's are a nice rig.
Question. Did they shorten the length of the front casting platform on the 1750 Fish Hawk? I've seen some older ones and the front deck looked like it was big enough for 2. The online pictures look like they've redesigned the layout.

Walleyedude
07-30-2016, 11:18 AM
I'd check with your dealer, but I wouldn't worry about adding a kicker to your boat.

I'm not sure where the idea that 25" shaft lengths are sailboat motors is coming from, 9.9 HP 25" kickers are actually quite common, especially on larger fishing boats. All of the manufacturers make them in their kicker lineups and the additional cost vs a 20" is minimal.

Buckhead
07-30-2016, 11:42 AM
25" xl leg high thrust kickers are not cheap. yamaha are upwards of 6g installed with all the options, the merc is 3600 for the motor alone. honda is 4100. And apparently the efi suzuki isnt available in Canada according to the one dealer.

The biggest reason i was inquiring about props is because my boat will not hit top end rpm. seems to only hit 4800 instead of mid 5's.

but what does it matter if someone you dont know wants to spend 210 dollars on a 2nd prop to make their time on the water more enjoyable.

I have similar size rig and normally run a17P prop. I can just hit the rev limiter with a light load.

The first thing I would check is your RPM's. Hook up something like a Tiny Tach directly at the outboard and get some rpm readings from that. The dash tachs on boats are notoriously inaccurate. From there you can tell if a 17 or 15P may be required.

A new prop doesn't have to be that expensive. I am assuming since you are running a 4 blade already - you would want the same.

A new Mercury Nemesis prop (4 blade aluminum) is about $150 including the GST. It comes without the hub - so you just reuse the one you already have.

If you are around Edmonton - PM me. I have a used 17P Nemesis that you could try out if you wish. It would be available in about 2 weeks.

2011laramie
07-30-2016, 09:29 PM
So all this started when my foot pedal on my powerdive v2 acted up and i was forced to troll with my main, and i thought it was too fast so i thought a lower pitch would slow the boat and allow me to reach the proper top end RPM.

Took the pedal into a shop few weeks ago and he looked at it and got it working on the bench. Today was the first day out with the "fixed" pedal... back to trolling with the main again lol. gonna park the boat in the garage and check all the battery connections and voltages for the minn kota.

I want to either get a gas kicker or ipilot. We do alot of trolling cause our little one is alot to entertain on the boat.

http://i1293.photobucket.com/albums/b584/08arcticcat/Mobile%20Uploads/IMG_4427_zpsrg3fhwjw.jpg (http://s1293.photobucket.com/user/08arcticcat/media/Mobile%20Uploads/IMG_4427_zpsrg3fhwjw.jpg.html)

http://i1293.photobucket.com/albums/b584/08arcticcat/Mobile%20Uploads/20160424_181337_zpszho9rxfh.jpg (http://s1293.photobucket.com/user/08arcticcat/media/Mobile%20Uploads/20160424_181337_zpszho9rxfh.jpg.html)

old dog
07-31-2016, 09:23 AM
I have a 1650 crestliner. I put the i pilot on mine when they came out. I love it. I also installed a long leg 6hp Mercury directly to the stransum. Trolls properly and no issues with it touching the water when in the up position (out of the hole or cruising the lake). I've not had any issues with it being mounted like that. But it is very light so not sure how a 9.9 would be