Welcome Guest - Sign Up today
Welcome Guest - Sign Up today

Announcement

Collapse
No announcement yet.

1988 Mariner 115 HP / Inline 6 / Whale Tail

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • 1988 Mariner 115 HP / Inline 6 / Whale Tail

    Any thoughts , Purchase the boat in Feb

    1984 Stratos with 1988 Mariner 115 HP / Inline 6 / Whale Tail / Rapture ss prop , jack plate

    I can't see any numbers on the prop ,

    With the whale tail , Boat gets on plane find , wot running 45mph @ 5200 , whale tail is below the water line , major drag , plus eating up fuel ,

    Without whale tail , boat fights to get on plane , wot running 49 @ 5500 , but when I back off wot the boat Porpoises really bad ,

    Help with any ideals on setting the boat up correctly ,

    Thanks Mike P.

  • #2
    Re: 1988 Mariner 115 HP / Inline 6 / Whale Tail

    Got any pics of your setup?
    "I hear and I forget. I see and I remember. I do and I understand."

    Haines Hunter V17C Half Cabin. Mercury V6 135 HP 1988.

    Comment


    • #3
      Re: 1988 Mariner 115 HP / Inline 6 / Whale Tail

      Most folks here recommend using trim tabs as opposed to whale tales, but it would be nice to see pictures of how your engine is mounted.
      1976 Rogers Custom Boats 18' "Bonneville" W/ Chevy 454/ Berkeley 12JC

      Care Taker of 1976 Glastron V-184 Crestflight W/ Volvo 170B/280 I.O.
      & 1969 Starcraft W/ 1956 Evinrude 7.5hp Fleetwin.

      Comment


      • #4
        Re: 1988 Mariner 115 HP / Inline 6 / Whale Tail

        I'll pull the boat out and get some pic's

        Comment


        • #5
          Re: 1988 Mariner 115 HP / Inline 6 / Whale Tail

          Mike, I think you will find the prop pitch to be 19". That sounds about right for the speed/RPM you are seeing. You might put a straight edge on your hull and see if she is true. You do have the motor tilted all the way down, right? The transom is at a right angle to the hull, right?

          Comment


          • #6
            Re: 1988 Mariner 115 HP / Inline 6 / Whale Tail

            Heres some pic's of the boat , I did measure prop to shaft , prop is 7in's below the pad.
            Attached Files

            Comment


            • #7
              Re: 1988 Mariner 115 HP / Inline 6 / Whale Tail

              Originally posted by MikeCustomBaitPainter View Post
              Any thoughts , Purchase the boat in Feb

              1984 Stratos with 1988 Mariner 115 HP / Inline 6 / Whale Tail / Rapture ss prop , jack plate

              I can't see any numbers on the prop ,

              With the whale tail , Boat gets on plane find , wot running 45mph @ 5200 , whale tail is below the water line , major drag , plus eating up fuel ,

              Without whale tail , boat fights to get on plane , wot running 49 @ 5500 , but when I back off wot the boat Porpoises really bad ,

              Help with any ideals on setting the boat up correctly ,

              Thanks Mike P.
              Sorry but what is a "Whale tail"

              Comment


              • #8
                Re: 1988 Mariner 115 HP / Inline 6 / Whale Tail

                Mike, The motor looks a bit high up. You do get to raise it up with the jack plate's setback, but it may be up too much. Why not drop it a bit and see if that helps. I could not see the length and type of boat. You may be overpropped for that boat.

                Comment


                • #9
                  Re: 1988 Mariner 115 HP / Inline 6 / Whale Tail

                  Charlie , a whale tail helps your boat get on plane faster as/well stops your boat from porpoising. Its mounted just above the prop & looks just like a whale tail.

                  Mike

                  Comment


                  • #10
                    Re: 1988 Mariner 115 HP / Inline 6 / Whale Tail

                    Chris ,

                    its a 1984 stratos , 18 ft , when I drop the motor down , should I remove the whale tail??

                    Mike

                    Comment


                    • #11
                      Re: 1988 Mariner 115 HP / Inline 6 / Whale Tail

                      Mike, I never liked whale tails. I would remove it and see what kind of performance you get. A stern heavy boat will probably benefit from the WT, but with that 300# motor, your boat is probably not stern heavy. Check the WOT RPMs. Prop to get them into range, and see what hole-shot is. Then install the WT or not as makes sense.

                      Comment


                      • #12
                        Re: 1988 Mariner 115 HP / Inline 6 / Whale Tail

                        Hey Chris

                        Thanks for the info

                        Mike P.

                        Comment


                        • #13
                          Re: 1988 Mariner 115 HP / Inline 6 / Whale Tail

                          If your whale tail is still in the water at planing speed, your outboard is mounted too LOW!
                          By your pictures I can see that it is mounted in the lowest position possible.
                          You need to get more of the leg out of the water.
                          The whale tail creates a lot of lift which helps get out of the hole quickly but needs to by totally out of the water on plane otherwise its a big drag.
                          As such they are only good on outboards!
                          And then only if adjusted correctly.
                          Try raising your motor up a hole to start and keep going higher until the prop cavitates under load then back down a hole.
                          However, I don't see any whale tail...

                          Comment


                          • #14
                            Re: 1988 Mariner 115 HP / Inline 6 / Whale Tail

                            Red ,

                            I removed the whale tail when I measured prop to shaft today & took pic's while it was off , its back on , I'll work on getting the motor up.

                            Since I haven't owned a boat for sometime , are you talking about raising the motor using the manual jack plate ?

                            Thanks for your in-put

                            Comment


                            • #15
                              Sign up today
                              Re: 1988 Mariner 115 HP / Inline 6 / Whale Tail

                              What do you use the boat for? Sking/tubing or fishing? The pic's you posted of set up height is about correct for a all around ski/fish set up as its not enve close to being high. If you just fish and want a little more speed raise engine about 2"
                              When in doubt,Trim it out!!!
                              Business Owner & Certifed Technician
                              Boats I own & use
                              20ft Javlin w/250 Junkrude
                              17ft Bullet w/200 Merc (SOLD!!)
                              13ft Allison w/150 I-6
                              17ft Hydra-Sport 175GT
                              15ft Allison w/75 Stinger(project)
                              14 x 48 Drifter with 1100SS Merc

                              Comment

                              Working...
                              X