Page 1 of 9 123456789 LastLast
Results 1 to 10 of 85

Thread: Fitting low water pick up to outboard engine

  1. #1
    Banned
    Join Date
    Jul 2012
    Location
    Berkshire, ENGLAND
    Posts
    261

    Default Fitting low water pick up to outboard engine

    High folks
    something ive never done and never seen in the flesh is a low water pick up for outboards.

    Im seriously thinking about raising my engine up around 4 to 5 inches to ride on the bullet or close to the
    bullet and dont know exactly how or where to make the low water pick up. ?

    Any advice or ideas including pics would be very good for me, i have a few ideas but probably totaly wrong.

    I was thinking about a transom mounted pipe with a slash cut to force water up when on the move,
    but will this work at slow speed ?

    The impellor is a lot lower in the water than a transom mount would be at slow speed and not sure if it would prime itself etc.
    is it best to fit one on the lower part of the gearbox at the front of the bullet ?
    my engine is a 56ci omc with normal gearbox not a racing gearbox, and realy dont want to change it.

    Also are nose cones the way to go, and do they realy just stick on with epoxy and stay put ?


    any advice will be good




    phill..

  2. #2
    FFX-61
    Join Date
    Aug 2005
    Location
    Stellwagan Ledges
    Posts
    1,968

    Default

    welded on, an SST 60 foot is the stock go fast set up for that Moda, heard someware that a Fast Fred Nitro foot is hot, that would fit.... thinkin there's a shot on hear ....

    Part one of "Secrets of the OMC Mod 50" : http://www.boatracingfacts.com/forums/showthread.php?t=2052

  3. #3
    Banned
    Join Date
    Jul 2012
    Location
    Berkshire, ENGLAND
    Posts
    261

    Default

    I dont want to change the gearbox.
    I want to keep the same gearbox and just put a low water pick up on it.
    I like the nosecone type of thing sold by bobs machine shop, but thought it very strange that
    it comes with epoxy to STICK it on.
    dont think i would trust a stuck on cone, but welded on yes, maybe they mean tack welded an the
    epoxy is just for finnishing and smoothing off ?.

    but i need to know a bit more about what i have to do to the original holes and where to drill etc.
    spme pics of anyone work they have dont to make this would be very good..


    phill

  4. #4
    Team Member
    Join Date
    Dec 2008
    Location
    north carolina
    Posts
    159

    Default

    I had a friend that decided to remove his nosecone it was bonded only by the epoxy kit inculed with kit.
    He chiseled, cut. beat an cussed a long time. Some notching an fitting is needed to fit various cases.
    Once a proper fit an aligmnent are achived you can tack weld then bond.

  5. #5
    Team Member LittleCharger's Avatar
    Join Date
    Mar 2011
    Location
    London,ON,Canada
    Posts
    166

    Default

    Where is the bullet relative to the bottom (pad) of the boat now? Seeing that you want to raise it 4 to 5 inches now it's pretty buried. I would invest in a water pressure gauge and raise the motor to see if the boat reacts to your liking. You should be able to raise the motor such that the center of the bullet is 2 to 2.5 inches below the pad and still have plenty of water pressure even without the low water pick up. Do you have access to surface piercing props to run when you raise the motor? Not all props liked to be surfaced.

    Cheers,

  6. #6
    Banned
    Join Date
    Jul 2012
    Location
    Berkshire, ENGLAND
    Posts
    261

    Default

    at the moment the centre of bullet is about 5 to 6 inches below the lowest point of transom.
    My engine is a longshaft, normal 20 inch transom on the boat, (actualy 20.5 inch.)
    I cannot raise anymore untill a jack plate is fabricated to what is gonna happen to handling etc.
    I will be using the boat for different things,so an adjustable plate will be need so i can run deep when at sea in
    rougher water at a reasonable pace.
    water pressure guage is a good idea and was thinking about ptting a fitting on the exhaust plate where there
    is a plugged off area with allen screw in it.
    (not sure if this is a good place, but got to be better than putting a tee in the pee hole as would be getting a
    true pressure reading of whats comming from the water pump)

    quote
    "You should be able to raise the motor such that the center of the bullet is 2 to 2.5 inches below the pad
    and still have plenty of water pressure even without the low water pick up."

    centre of bullet is 7 inches from cav plate so to get bullet 2 inch below boat bottom would need the engine rasie by 5 inches.
    I honestly dont think ill get any water at that height, the water pick ups are a few inches above the bullet !!!!!



    phill

  7. #7
    Team Member
    Join Date
    Jul 2011
    Posts
    137

    Default

    Phil, the sst60 foot does not have bottom pickup and they do just find, I run my 15" nitro case with the two top pickup holes block off at 21.5" high and I have no water pressure issue. Get a water press. gauge, tee it in the pee hose inside the cowl for reassurance. Raising the motor 5" wont be a problem, find a good prop and you're good to go.
    Mike

  8. #8
    Banned
    Join Date
    Jul 2012
    Location
    Berkshire, ENGLAND
    Posts
    261

    Default

    I shall have to get a jack plate and a guage and give it a try.
    but i realy dont think ill get enough water.

    when i tried a little 4hp merc on the back of my boat it didnt get enough water and that is a 15 inch shaft.
    but i shall give it a try and see what happens.
    i was under the impression that a nosecone would also give better performance , but if not gonna gain it might not be
    worth doing.
    I just fancied giving a few little extra bits of performance .

    Now being as the engine will have gone back by 4 inches when i fit a jack plate how far from the bottom of the boat should the bullet be then.

    The way im reading this is the engine needs to have the bullet just 2 inches lower than the pad.
    So if the boat was a 23/24 inch transom i would be fine.
    But using a set plate /jack plat that goes back another 4 inches, does the engine need to be even higher ?
    if so with 4 inches of set back what height should the bullet now be ?
    should it be 2 inches higher than bottom of boat, or about centre of bullet level with bottom of boat.

    this does seem to be extremely high to me.


    phill.......

  9. #9
    Team Member
    Join Date
    Jul 2011
    Posts
    137

    Default

    From what I understand, you are doing all this to a 13' Boston Whaler type of boat. Not all small boats like set back, I would start with the shortess setback you can find and raise the motor 5", then you can raise it or lower it at will.
    P.S. While you're at it change the water pump.
    Mike

  10. #10
    Banned
    Join Date
    Jul 2012
    Location
    Berkshire, ENGLAND
    Posts
    261

    Default

    why water pump change ?
    what would be a better water pump ?
    never knew about different water pumps, i thought the high volume pump on this engine would be fine ????

    Without some form of setback its not gonna be possible to raise the transom height.
    unlike a normal speedboat you cannot get to the transom woodwork to beef it up.
    The only way to rais eit would be to use metal plates with a wooden insert that would
    be very heavy on the rear end.
    Or if i had a stanless hollow block made up for it to try and keep weight down to minimum.
    thats why i was opting for a setback jack plate type thing.



    phill

Page 1 of 9 123456789 LastLast

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Low water pick up Nose cone for 50hp
    By gtf1 in forum Technical Discussion
    Replies: 20
    Last Post: 07-01-2014, 01:08 AM
  2. The Ultimate Outboard engine design
    By Skoontz in forum Motors and Powerheads
    Replies: 25
    Last Post: 07-21-2013, 12:17 PM
  3. mercury low water pick-up nose cone
    By Arkansas river rat in forum Technical Discussion
    Replies: 2
    Last Post: 01-23-2011, 07:07 PM
  4. Low water pick up
    By looseunit225 in forum Technical Discussion
    Replies: 2
    Last Post: 01-17-2009, 09:17 PM

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
  •