Need a stainless steel impeller for a Mercury 25/20

Discussion in 'Boat Tips' started by Semper_Fi, Dec 17, 2006.

  1. Semper_Fi

    Semper_Fi New Member

    Messages:
    36
    State:
    Pennsylvania
    I am considering a newer Mercury outboard jet for my Lowes' Roughneck 1448, but after reading the article on jet engine performance, I'm wondering if a stainless 4 blade impeller wouldn't be a better solution. The boat performed well until I added a wooden floor and front trolling motor and battery. Now it is slow coming up on plane and with another person, almost impossible. My problem is I cannot find a source for the replacement impeller............ anyone know of one?

    Thanks,
    Ernie
     
  2. boliver

    boliver New Member

    Messages:
    198
    State:
    Rudy Ark
    i guess you mean propeller, go to the mercury marine website and get the part #. then you can either get one there or go to ebay and look in boat parts there is usually a lot of them listed if you are lucky one may fit you motor. good luck. boliver
     

  3. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    What has happened is the added weight won't let the engine reach its potential rpm's. What you need to do is drop one size in you pitch on the propeller. If you add a SS 4 blade prop at the same pitch you have now it will slow that engine down even more.
    There are other alternatives to getting it up on plane faster.
     
  4. Mark J

    Mark J New Member

    Messages:
    9,407
    State:
    Four Oaks, NC
    3/4" plywood is overkill. Treated plywood is saturated with water and in a boat its doubtful it would ever dry out.

    Plywood floors in boats are typically 1/2".
    A sheet of 3/4" inch exterior grade North American plywood weighs about 69 pounds give or take a few pounds by species.
    Your Southern yellow pine treated plywood would be up around 85 pounds a sheet depending on water content.

    What I would do.
    Either use a product called Nidacore. It seems expensive at first glance and you can buy it one of two ways. Already glassed or unglassed.
    It's lightweight and comes in thicknesses up to 2 inches thick.

    Or buy 1/2" exterior plywood Glass the topside with a 12oz biaxial fabric using epoxy and just put 3 to 4 coats of epoxy on the bottom side and the edges.

    When you do the math neither of these options is over the top expense wise for a floor that will last.

    There are many products available that are made for boats that are proven to last that virtually anyone can work without special skills or tools.

    Its a false economy to cut corners in order to save money when putting wood in a boat. You have to do it right or you'll do it over and over again putting you well above the cost of doing it right one time.

    How much faith do I have in the products made today for wood boats?
    Alot. It's all I'll ever own. You cant beat the weight to strength ratio of plywood verses aluminum or fiberglass.
    Alot of your multi million dollar sportfish boats are sheathed entirely in plywood/fiberglass/epoxy and they spend year after year sitting in saltwater other then the occasional haulouts for hull scraping. Usually bi annually.

    When building a boat or adding to a boat the first thought is saving weight.
    It's not a house. Your boat floor doesn't maintain the same live loads or dead loads incurred in a house. Build accordingly.

    If you are on the lower end of horsepower the boat is rated for building light is even more paramount. You cant force an engine to put out more then its rating. Going to a stainless steel prop would be a waste of money in this case. It wont fix a weight issue.
     
  5. Semper_Fi

    Semper_Fi New Member

    Messages:
    36
    State:
    Pennsylvania
    I'm sorry, I didn't explain my motor clearly enough. It is a 25/20 jet. The article in the Pennsylvania Angler claimed an increase of approx. 18% by replacing the three blade impeller with the 4 blade stainless one. I figure that should be enough to solve my problem.

    Ernie
     
  6. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    Now that does make a difference in the outcome ernie. I don't know much about Jet drives but with what mark posted above is the way to add or redo the inside of a boat.


    I went back an re read the post ernie and you did mention the jet and that was my Bad on not reading what I was reading.
     
  7. Semper_Fi

    Semper_Fi New Member

    Messages:
    36
    State:
    Pennsylvania
    Mark, thanks for taking the time to reply to me. What thickness would you recommend in the Nidacore? Also, I failed to state the reason for the aluminum boat is because we run a lot of 'skinny' water on the NE Susquehanna River. I had a Ranger and it just couldn't do it....... or at least I wasn't about to try! :lol:

    I put the 3/4 treated in thinking(?) that it would last as long as me, but I never thought about the excess weight it carried. I'm sure it must come out and be replaced by something because I don't have the balance I had in my youth and need a flat floor so as not to go smimmin'! LOL

    Ernie
     
  8. Bobpaul

    Bobpaul New Member

    Messages:
    3,039
    State:
    Supply NC
    If you want a floor that you can remove, use 1/4 inch and 1x2 frame work under it. It works in a boat I've got. Keep it painted and if it goes bad in a few years, you've got the pattern to make a new one.

    Being able to remove the floor is important in aluminum boats. Easy to check for leaks and clean up.
     
  9. Mark J

    Mark J New Member

    Messages:
    9,407
    State:
    Four Oaks, NC
    Using Nidacore I couldnt say. I would have to research it. Alot of yacht builders are using Nidacore for decks now. Neat and lightweight, A 1/2" finished Nidacore panel runs 240.00 a sheet. Unfinished around 120.00 a sheet.

    Running skinny. I'll do some of that skinny water but not really skinny.
    At any rate I'm loading epoxy with graphite powder and 4 coating the bottom of my next build. It'll stand up to oyster beds quite well.
    I could lay a layer of kevlar on the bottom or inside the hull on the bottom for puncture resistance but its not really worth it. This boat wont sink with a hole the size of a basketball through it. There will be enough flotation foam in the hull to float 1800 pounds or so. The hole would probally slow me down though:big_smile:
     
  10. Semper_Fi

    Semper_Fi New Member

    Messages:
    36
    State:
    Pennsylvania
    Thanks, Guys! After more research and help from others, I now realize that the stainless steel impeller would only help me with my problem if my motor was 100+ horsepower.(which it isn't) I either have to bit the bullet on weight reduction or go bigger on the motor.

    SF
     
  11. Semper_Fi

    Semper_Fi New Member

    Messages:
    36
    State:
    Pennsylvania
    I emailed the Mercury dealer today about the availability of the new 40/28 jet that was reported to be available in January, 2007. Based on the price, I'll have to make a decision. Maybe the 1/4 inch floor and cutting back to one tank of gas on board might be the best answer. Jiger Jim suggested on another forum that I could lose some weight.... I'm revaluating my friends list as we speak! :big_smile: I used to think highly of him. :roll_eyes:

    Ernie
     
  12. Mark J

    Mark J New Member

    Messages:
    9,407
    State:
    Four Oaks, NC
    You just need a bigger boat:tounge_out:
     
  13. Semper_Fi

    Semper_Fi New Member

    Messages:
    36
    State:
    Pennsylvania
    Mark, you are right, but that just ain't gonna happen right now. I just heard back from the local dealer and it looks like the boat is going to hafta lose some weight. :angry:

    "I have not heard when the 40/28 jet will be released. The 30/25 will be out in Jan. The tiller manual start will cost $4835.00, the tiller elec. will be $5145.00, and the elec. remote control will be $5420.00. "

    That's about 2 grand more than my 25/20 was two years ago. Thank you everyone for your help on this topic!

    Merry Christmas,
    Ernie