Page 1 of 2 12 LastLast
Results 1 to 20 of 35

Thread: Surface drive prop pitch????

  1. #1

    Default Surface drive prop pitch????

    I have a Yukon Freightworks 18 foot Taiga Creek model freighter canoe paired with an 18 horse copperhead surface drive. I am very pleased with the boat and very pleased with the motor so far after about a hundred and 20 miles of use over the last year. However I am not happy with the boat motor combination. I think my problem may lie with the prop pitch. Last Fall in a failed attempt to head 100 miles up river with about 900 pounds of food, gear, people, motor and fuel I discovered that the setup was no match for the trip planned. I was only able to make about 4-6 miles an hour against a 4 mile an hour current and I was throwing out a huge wake. The boat was constantly struggling to climb up on step but couldn't even begin to accomplish the feat. I am not expecting any speed demon but would like to see some more respectable speeds. I believe that I had the load distributed well in the boat for balance so I do not think that that is the issue.

    I can not determine what pitch prop I have. I find no indication anywhere on the prop. I was told the marking is on the hub and is visible without removing from the motor. I still cannot find it anywhere.

    Since I could never sense that the motor was ever under any strain, I was under the impression that I need a prop pitched more for speed. After just talking with Copperhead however, I understand that they feel I need a prop pitched more for power.

    I am new to all this prop pitching stuff and am lost. Any advice?

  2. #2
    Member skybust's Avatar
    Join Date
    Oct 2006
    Location
    alaska
    Posts
    2,427

    Default

    Have you called copperhead they are good people and should be able to help you
    Is it opening day of duck season yet
    Member of Alaska Waterfowl Association

  3. #3

    Default

    Quote Originally Posted by skybust View Post
    Have you called copperhead they are good people and should be able to help you

    Yes, As I said above.

  4. #4
    Member skybust's Avatar
    Join Date
    Oct 2006
    Location
    alaska
    Posts
    2,427

    Default

    Quote Originally Posted by mountain joe View Post
    Yes, As I said above.
    Sorry about hope you get a good answer
    Is it opening day of duck season yet
    Member of Alaska Waterfowl Association

  5. #5
    Moderator stid2677's Avatar
    Join Date
    Apr 2006
    Location
    Fairbanks Area
    Posts
    7,277

    Default

    You need more motor or less weight,, more pitch will equal more speed/less power. Less pitch more power/less speed. Since you stated it was struggling to to get on step and too slow, you are under powered and or over weight.
    "I refuse to let the things I can't do stop me from doing the things I can"

  6. #6
    Member AK Ray's Avatar
    Join Date
    May 2006
    Location
    South Central
    Posts
    2,543

    Default

    See if there is the ability to improve your ratio between the prop shaft and motor shaft belt pulleys. I would think that they would already be setup at optimum for the motor RPM/HP and prop purposed pitch. A larger pulley on the motor shaft with a smaller one on the prop shaft will increase your prop speed. Can this style/size of prop use more RPM?

    I don't know if copperheads need to be a true surface drive where the prop should be half out of the water to achieve its purpose. Is your motor height set up to allow for this based on load? I would guess that this canoe has an adjustable transom.

  7. #7
    New member
    Join Date
    Apr 2006
    Location
    Palmer, AK
    Posts
    36

    Default

    If you have run it in any silt or sand you may need a new prop. Props make such a big difference with mud motors.Your 18hp motor is on the low end, power wise, for the loads and conditions you are running. To find the pitch and size of your prop, you may have to remove it and you may not be able to tell then. It depends in who made the prop, some are just scratched on, that you can barely read when it was new. If it was mine I would get a new prop, what ever size copperhead recommended for what you want to do with it. I would also keep and eye out for at least a 23hp Surface Drive.

  8. #8
    Member
    Join Date
    Sep 2008
    Location
    Whitehorse, Yukon
    Posts
    437

    Default

    Quote Originally Posted by mountain joe View Post
    I have a Yukon Freightworks 18 foot Taiga Creek model freighter canoe paired with an 18 horse copperhead surface drive. I am very pleased with the boat and very pleased with the motor so far after about a hundred and 20 miles of use over the last year. However I am not happy with the boat motor combination. I think my problem may lie with the prop pitch. Last Fall in a failed attempt to head 100 miles up river with about 900 pounds of food, gear, people, motor and fuel I discovered that the setup was no match for the trip planned. I was only able to make about 4-6 miles an hour against a 4 mile an hour current and I was throwing out a huge wake. The boat was constantly struggling to climb up on step but couldn't even begin to accomplish the feat. I am not expecting any speed demon but would like to see some more respectable speeds. I believe that I had the load distributed well in the boat for balance so I do not think that that is the issue.

    I can not determine what pitch prop I have. I find no indication anywhere on the prop. I was told the marking is on the hub and is visible without removing from the motor. I still cannot find it anywhere.

    Since I could never sense that the motor was ever under any strain, I was under the impression that I need a prop pitched more for speed. After just talking with Copperhead however, I understand that they feel I need a prop pitched more for power.

    I am new to all this prop pitching stuff and am lost. Any advice?

    Ok..something is out of wack. For my Hudson Bay I have noticed that more weight in the front of the boat gives me a couple of more miles an hour. Also I bury the prop in the water and even with my 14 HP I think I could get up to 8MPH+ against a 4MPH current

    A Canoe is a semi-displacement hull so it will only ever get half up on step but I think you should get more speed. I only bring about 750 pounds up stream might be worth testing speed on a GPS with the weight distributed differently and a little lighter load. Is the longer hull and bigger boat-tail of the Hudson Bay making a difference? I don't know.

    No idea about the Prop pitch as I am just running factory...I suspect that maybe more power would help. Maybe Michael would let you experiment with the 23 and offer a good trade?

  9. #9

    Default

    Thanks everyone for the advice. I'm gathering that with my size motor it may gain me some more speed by going to a prop that is pitched for power rather than a speed pitched prop. Am I going to see much of a difference in speed? Should I see as much as 5 miles an hour increase? If I can gain 5 miles an hour over what I am doing now. I will cut my upriver journey time in half.

  10. #10
    Member
    Join Date
    Sep 2008
    Location
    Whitehorse, Yukon
    Posts
    437

    Default

    Quote Originally Posted by mountain joe View Post
    Thanks everyone for the advice. I'm gathering that with my size motor it may gain me some more speed by going to a prop that is pitched for power rather than a speed pitched prop. Am I going to see much of a difference in speed? Should I see as much as 5 miles an hour increase? If I can gain 5 miles an hour over what I am doing now. I will cut my upriver journey time in half.

    I found this for you in another forum

    "Not sure whether you are aware of this, but everything in prop design/selection is a balance/tradeoff.

    If the boat is already propped correctly and you go lower pitch, you typically get better low end, but slower top end. If your boat/motor combination is currently overpropped (too high pitch) and you are lugging the engine, it is possible that you could get better performance both on the low end AND high end by going to a lower pitch prop, but ONLY if you are currently overpropped.

    Sometimes with a big/heavy boat one can get a better hole shot and load carrying with a larger diameter, but only if the engine has the power to handle the additional diameter. If you go too big in diameter, performance will suffer all the way around. If your prop diameter is too big, you would get more mid range and top end by going down in diameter.

    Call Copperhead. They have already tested pretty much every prop size and can both sell you one for what I personally think is a pretty good price or recommend one. You could also call Hopkins which made the original Copperhead propellers (not sure who is making the current ones)."


    Below is the information re Hopkins.

    http://www.hopkinspropeller.com/mudprops/

    Another discussion on the 18

    http://www.mudmotorchat.com/forum/vi...?t=587&p=14060

  11. #11
    Member mainer_in_ak's Avatar
    Join Date
    Sep 2008
    Location
    Delta Junction
    Posts
    4,078

    Default

    I just saw this mountain joe,

    One of the better options, is to go to a larger diameter prop, with less pitch. As surface drives go up in horsepower, oftentimes the pitch becomes more aggressive, while the diameter shrinks slightly.

    you have plenty of power for the boat, but for the currents you described along with the size of the load, a prop change will be best. Also, hang along the eddy water as much as possible, trying to stay out of the faster currents, it will save you fuel.

    One gentlemen this year hauled a 62 in racked moose and a 54 in racked moose with the 18 taiga/18 hp combo. Sometimes with loads like that, as he probably learned, a second trip might be necessary.

    Think of your boat in "thirds" and move the weight away from the first third of the boat (bow end). You want your bow to ride high and you'll get less wake if you do this. Try to keep the "fluff" like sleeping bags up front.

    What river was this on again?

  12. #12
    Member
    Join Date
    Apr 2006
    Location
    Fairbanks, AK
    Posts
    554

    Default

    Are you sure about the weight? Whatever you really have, it sounds like it is too much. You should not be "throwing a huge wake". Have your partner swim, and/or get his/her own canoe. I take that much weight in my Hudson Bay w/ a 23 hp MudBuddy (about 12 mph, 16 empty) and I'd not like much more in my larger canoe. Also, I'd be careful putting "fluff" up front too much, as you lose stability and you plow more, in my experience, reducing speed and safety. I don't like my bow much out of the water, but if it is sticking in too much you dart around and slow down. BTW: What are you going to do if you add a moose to that load? TWO CANOES!

  13. #13
    Member
    Join Date
    Mar 2014
    Location
    Missouri
    Posts
    16

    Default

    Quote Originally Posted by jklingel View Post
    BTW: What are you going to do if you add a moose to that load? TWO CANOES!
    Second canoe or find a Scott James Bay. Mine came from the factory with a 50 hp. Honda, useful load according to the factory was just over 4000lbs but Canadian registration cut it to 3590lbs or so. Very stabile, handles large loads, big water/waves well, portage is out though..... Needs about a 1200lb load to settle it down and ride nice!

  14. #14

    Default

    Quote Originally Posted by jklingel View Post
    Are you sure about the weight? Whatever you really have, it sounds like it is too much. You should not be "throwing a huge wake". Have your partner swim, and/or get his/her own canoe. I take that much weight in my Hudson Bay w/ a 23 hp MudBuddy (about 12 mph, 16 empty) and I'd not like much more in my larger canoe. Also, I'd be careful putting "fluff" up front too much, as you lose stability and you plow more, in my experience, reducing speed and safety. I don't like my bow much out of the water, but if it is sticking in too much you dart around and slow down. BTW: What are you going to do if you add a moose to that load? TWO CANOES!
    Yes I understand about proper loading and balancing. My first canoe and outboard was over 30 years ago. The weight quoted is an estimate but I feel that it was in the ball park. A lot of that weight (approximately 300 lbs) was fuel due to the distance I was wanting to travel. I have no concern about throwing in a moose as far as the boat capacity and ability to handle it. It is all downstream so I really don't care if I have to idle all the way back if I have to.

    Quote Originally Posted by mainer_in_ak View Post
    I just saw this mountain joe,
    One of the better options, is to go to a larger diameter prop, with less pitch.......
    Since these props are in the neighborhood of three hundred dollars or so, I would not want to make a mistake. First of all I don't have a clue as to what prop I have as any and all marking are apparently gone. Copperhead said if I understood them correctly, that they sell the 10 pitch and the 12 pitch. I don't know which one I have and so therefore do not know which one to try as an alternative. Do you have an assortment of pitched props for the 18 horse that I could come up there this Spring an try out on a local lake? I need to get this figured out to where I am happy with the setup. I talked to somebody who has the 23 copperhead on their Taiga creek and they are apparently getting the kind of performance that I was hoping to get with mine. So either I will have to pitch my motor differently and see what happens or I will have to fork out the bucks for a larger motor. One way or another I need to work this out.

    Thanks everyone for the advice and help so far.

  15. #15

    Default

    go with the 23hp and dont look back. you dont have enough power to drive that load upstream. even with a bigger prop. with all the cool trips you do, you will always be able to use those extra horses. that 18 is only one season old you should be able to get a good price for her.

  16. #16

    Default

    Quote Originally Posted by mainer_in_ak View Post
    .......One gentlemen this year hauled a 62 in racked moose and a 54 in racked moose with the 18 taiga/18 hp combo........
    I'm sorry but I'm quite sure you have the motor sizes mixed up on this one. That was a 23 horse, not the eighteen. I know of the gentleman and boat motor combo you are most likely referring to.

  17. #17
    Member mainer_in_ak's Avatar
    Join Date
    Sep 2008
    Location
    Delta Junction
    Posts
    4,078

    Default

    Quote Originally Posted by mountain joe View Post
    I'm sorry but I'm quite sure you have the motor sizes mixed up on this one. That was a 23 horse, not the eighteen. I know of the gentleman and boat motor combo you are most likely referring to.
    OK, yes it's a 23hp.
    No problem with testing some different gearing and prop options when things are thawed. There's also very frequent interest in used units and always refer those interested to current copperhead owners. We can also slap a 23 hp on the transom as well, and get a feel for both a prop or gearing change, or more HP. Did you by any chance fashion a home-made rock guard? Sometimes those can effect performance as well. Gotta have a 60 degree bevel on the UHMW for compatibility with a cupped surface piercing prop. I do plan to have a seminar in Anchorage and Fairbanks this spring to talk in person about running these things and discuss hunt planning, maintenance, and load distribution. If anything, they will be good events to network with other hunters that have equal capabilities. I will post dates and locations after the Iditarod, as I'll be in Nome to pack up tired dogs in a few days.

  18. #18

    Default

    That sounds like an awesome offer of assistance. If I can try out different prop pitches as well as more horse power that should clinch the search and give irrefutable proof as to what is needed to get this outfit set up to run it's optimum. Thanks Michael. I was using a rock guard at times but most of the time I was not using a guard so as to gain every little ounce of oooomfff. It was your rock guard that you manufactured that I was using.

  19. #19
    Member mainer_in_ak's Avatar
    Join Date
    Sep 2008
    Location
    Delta Junction
    Posts
    4,078

    Default

    One more thing on the bow, the transom has good width, so no matter how far back you store your weight, you will never porpoise at the bow, as the stern stays dry, unlike wine glass sterns that have a tendency to bite deep into the water.

    If you recall on our test drive mountain, that 20 hp honda of customer David's canoe was starving for water and cavitating with the rock guard. I moved two 200+ lb passengers to the rear seat, and was back there myself, trying to get that motor to bite some water. 600 lbs did it. The buoyancy of that foam core fights the surface of the water.

    It is my belief that the 18 hp is plenty of power within the limitations of the 18 ft canoe. I would not hesitate to hang that motor off a 22 foot canoe either.

    Back 7 or 8 years ago, when I was testing the 12 hp copperhead (the biggest motor at the time), I believe the diameter of the prop was 11 or 12 inches with very little pitch. As Copperhead Manufacturing continued testing and development, I noticed that the 23 hp motors began sporting a more aggressive pitch with less diameter, catered for top speed with mud boats. Some other companies have referred to the 12" prop as the "big blade prop". And these really let the 30 ft. lbs of torque come in strong with the low planing speed of the 18 ft taiga creek. All you need, is about 7-8 mph to get on step with a load like that (going up river) The big blade props and a possible a 2 tooth change of the upper cog, will give you the thrust you need to get into the window of fuel economy.

    Torque, is what your freighter needs with a load, by golly that 18 hp throws 30 ft-lbs of that good stuff.

    Anyhow, customer David beat up his rock guard and prop something aweful on his 20 hp, and he's wanting another surface drive to replace his 12 hp. Last time I heard from him, he sent me a GPS link to his location between the Kandik and Circle. Lucky guy.....he's playing out there in the Yukon all season long, following the Yukon Quest trail. Between now and this summer, he'll be in the market for a new or used copperhead, so if you decide "mo powah" I could send you his contact info Mountain Joe.

  20. #20
    Member mainer_in_ak's Avatar
    Join Date
    Sep 2008
    Location
    Delta Junction
    Posts
    4,078

    Default

    Fuel weight.

    Jet boaters can vouch for this: Cache fuel where you expect you'll need it. The physics of this method was tried and true yesterday, and it's tried and true today.

    Back in 2011, I tried to make a chute of white water with the 12 hp copperhead, and it felt a bit sluggish. I turned back around, hid 10 gallons of gas behind the kandik mouth cabin, and an Army duffel bag full of big tools like a splitting maul, a cast iron frying pan, big wrenches and other heavy tools unnecessary for the rest of the trip.

    It probably only amounted to 200 lbs of junk, but it made a world of difference. I continued dozens of miles up the Kandik, even cutting through the class lll Johnson's gorge with 12 hp and 18 ft lbs of torque, In a canoe that was very similar to the production model Taiga Creek, and was much heavier.

    Old sourdoughs in that region would let their sled dogs out of the boat, and they'd run along the river bank back home, following their owner in the boat, back in the day. Shaving weight in dah gas boat, do it!

Page 1 of 2 12 LastLast

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •