User Tag List

Thanks Thanks:  0
Likes Likes:  0
Page 2 of 2 FirstFirst 1 2
Results 16 to 22 of 22
  1. #16
    Join Date
    May 2006
    Location
    New Zealand
    Posts
    190
    Thanks (Given)
    1
    Thanks (Received)
    0
    Likes (Given)
    0
    Likes (Received)
    1
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Need to move a big mass of water if that machine is as heavy as it looks. Hamilton 212... yeah, they are a good pump, but you might be a little light on hp with the 305 to drive it. I'd likely opt for something from SDM, better speed (not as good as a Berkley) with good thrust, huge ass ducted reverse bucket like the 212, but come standard with the trim nozzle so you can still trim the boat... and throw that wall of water...

    My 2c

  2. #17
    Join Date
    Apr 2009
    Location
    Canada
    Posts
    12
    Thanks (Given)
    0
    Thanks (Received)
    0
    Likes (Given)
    0
    Likes (Received)
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Its not as heavy as it looks, it actually got up and went with a 90hp inline 6. It has a really flat bottom and doesn't draw much water.

  3. #18
    Join Date
    Sep 2006
    Location
    Calgary, Alberta, Canada
    Posts
    186
    Thanks (Given)
    0
    Thanks (Received)
    0
    Likes (Given)
    0
    Likes (Received)
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I think we're basing our thoughts/recommendations on a few things.

    Firstly you're 21 feet which is towards the "larger" end of the jetboat scale when it comes to length.

    It appears in the picture you have between 25% to maybe as much as 100% more freeboard than alot of jetboats

    At 10 feet in beam you are substancially over the average jet hull by maybe 2+ feet

    Being fibreglass construction and of that vintage its safe to say thats just physically "alot of boat" and its probably heavy compared to most jets powered by a Berkely style mixed flow pump. Aluminum hulls are far lighter and the presense of what appears to be a cuddy cabin in yours also adds weight which most jet boats wont have

    In my previous job probably 90% of the boats over 20 feet with beams aproaching 102" all received axial flow style pumps regardless of motor size.

    Im not sure how much you know about Berks yet but basically the impellers are 'cut down' from the largest size to be compatable with lower HP engines. I.e a cut down AA is an A, which is cut down to make a B etc etc Smaller impeller sizes require less HP to spin at a given RPM

    A small block powered boat will require a smaller impeller (maybe a B or even C) to spin effectivly with the power of a 305. However that means its inherrently less efficient than an AA impeller(youve basically cut away portions of what moves the water) especially when it comes to moving more weight.

    Alternatly axial flow pumps, like the Hamilton, work quite well with small blocks and still move a tremendous amount of water. In fact a Hamilton pump with a smaller engine will still move a big boat quite effectively. With an axial pump adding more HP tends to have more effect on planing time and load carrying ability than on top speed. (Hamiltons seem to eventually "hit a wall" in top speed when it comes to adding HP, more power wont increase top end)

    Adding more HP to a Berkeley pump will have more effect on top speeds than its ability to plane and carry loads because its only moving half the amount of water at a given rpm. While they usually show gains in top speed when more power is added eventually it becomes difficult to get a big enough impeller to 'hold back the HP'. Racers use "over standard" impellers as big as AAAA, but spin them at 5-6k using over 1000 HP

    Sounds like you're on your way already with the Berkeley so its too late but Its not too late to consider power. I may be tempted to consider a big block in a boat that size to allow you to stay with a larger impeller etc

    Hope this helps

    Cheers

    p.s. lets see more pics!
    "If you ain't hittin bottom.....you ain't jetboatin!"

  4. #19
    Join Date
    Apr 2009
    Location
    Canada
    Posts
    12
    Thanks (Given)
    0
    Thanks (Received)
    0
    Likes (Given)
    0
    Likes (Received)
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    So I started to tear my engine apart to rebuild the heads and put new gaskets in. The valve cover says mercrusier 305 but after removing the manifolds and valve cover and pulled the heads...its definitely not a 305...its a 350! So it was a nice surprise and I bought this engine real cheap thinking it was a 305.

  5. #20
    Join Date
    Jun 2009
    Location
    indianapolis
    Posts
    4
    Thanks (Given)
    0
    Thanks (Received)
    0
    Likes (Given)
    0
    Likes (Received)
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I have a 64 Buehler contessa 16' with a 318 Crysler. The boat does not perform like similar set up Buehlers. It is a little slow especially in turns. Engine runs fine,should be enough power. any ideas?

  6. #21
    Join Date
    Apr 2009
    Location
    Canada
    Posts
    12
    Thanks (Given)
    0
    Thanks (Received)
    0
    Likes (Given)
    0
    Likes (Received)
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    So I have my jet drive mounted and in place. My controls are next to get installed and was wondering about the quicksilver control rod(not sure the part name) that I believe controls the trim of the jetovator. Well the cable to that was cut off by the previous owner probably for quick removal, how do you replace that cable or do you have to replace the whole assembly looks like it does not disconnect. Also anyone have any pictures of how to properly hook it up?

  7. #22
    Join Date
    Apr 2009
    Location
    Canada
    Posts
    12
    Thanks (Given)
    0
    Thanks (Received)
    0
    Likes (Given)
    0
    Likes (Received)
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Its the cable system with the spring mechanism.

Page 2 of 2 FirstFirst 1 2

Posting Permissions

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