Hydrofoil+ prop change... works excellent but bought blew my water pump!

Discussion in 'Boat Repair Help' started by dixiedrifter, Jun 2, 2006.

  1. dixiedrifter

    dixiedrifter New Member

    Messages:
    102
    State:
    Tennessee
    Good news. Hydrofoil and prop change from aggressive who knows what to OEM 10 degree pitch prop worked wonders. Boat is now getting up on plane quick and runs very smooth but I did lose a little bit of top end speed as best I could tell.

    Bad news. Hydrofoil is interfering with water pump intake... motor was pumping water at idle but when I got out in the main channel and opened her up the sky opened up as well...in the process of making a quick turn around and getting back to the dock I didn't notice that the motor was not peeing!!!! :eek:oooh: Apparently the hydrofoil worked too good, lol. It picked the back end of the boat up enough so basically there wasn't any water flowing into the inlet.:confused2: Fortunatly all is well that ends well. I inspected the water pump and it has a little bit of wear on it so I flipped it over and reinstalled it. It also appeared to have one of the rubber impellers in there running backwards...

    Sooooo.... it looks like the hydrofoil is going to have to go for now until I can find a way for it to pick up water when the boat is up on plane.:sad2:

    Will post pics later after I get done dragging my hay baler over to my friends house to get it up and running again.
     
  2. Bobpaul

    Bobpaul New Member

    Messages:
    3,039
    State:
    Supply NC
    That's the first time I ever heard of turning an impellor over and trying to use it.

    Let me know how it turns out and how many hours you get on it. I've got plenty I could recycle instead of throwing them away. Stupid me!:crazy:
     

  3. ShilohRed

    ShilohRed New Member

    Messages:
    4,339
    State:
    West Tn
  4. dixiedrifter

    dixiedrifter New Member

    Messages:
    102
    State:
    Tennessee
    My particular has impellers that have small lobes on them... when they are against the pump housing it makes it to where the impeller has a wider contact area with the outside of the pump creating a better seal than if the blades were just flat... now the lobes had quite a bit of wear on one side, so when i flipped them over it effectively put more rubber to the pump housing. Get it now? But once they are so far gone there ain't much you can do for them.

    Anyways, this is the hydrofoil called a doel-fin made by Davis Mfg. The second and third picture shows how the engine is mounted... all the way down and the anti-cavitation plate is about 2-3" from the bottom of the boat.
     

    Attached Files:

  5. dixiedrifter

    dixiedrifter New Member

    Messages:
    102
    State:
    Tennessee
    Now then, the next pic is the inlet, which consists of three very small holes...

    The pic after that is of the props... the prop on the bottom was the one I was using before of an unknown pitch, the one on the top is an OEM prop with a 9 pitch... the black prop on the boat is an OEM prop with a 10 pitch. Notice how much more agressive the prop is on the bottom compared to the top.

    Lastly is a pic of the crap inside my boat. As you can see, not a whole lot of stuff in there for those thinking I got too much weight... when empty it sits in the water with the water line being right below the line running down the side of the boat.
     

    Attached Files:

  6. dixiedrifter

    dixiedrifter New Member

    Messages:
    102
    State:
    Tennessee
    Whoops the props didn't load... here they are.
     
  7. dixiedrifter

    dixiedrifter New Member

    Messages:
    102
    State:
    Tennessee
    One more try...
     

    Attached Files: