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*new-to-me '93 9.9 4-stroke several issues*

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  • *new-to-me '93 9.9 4-stroke several issues*

    I found a really nice-running T9.9ELRH, freshwater-only, after an exhaustive 10-days search in the northeast

    the only issue, the PO said, was slowly it loses fuel pressure as it runs, and dies
    I thought it might a blocked vent in the tank, or the check valve in the prime bulb, and the engine purred so quiet and ran so well, and the price was so good, that I bought the motor

    now trying to troubleshoot several issues:

    1. fuel pressure:
    it is not a blocked vent - same issue if you unscrew the fuel fill cap and have plenty of air back pressure
    it *may* be the check valve in the prime bulb - bought a new bulb, and will install shortly (I am not at the boat right now)
    possible fuel pump diaphragm? any other possibilities? anyone else experience similar symptoms?

    2. vertical lock
    the lever on front that is supposed to lock the motor down in place or up at an angle (for planing, etc) does not work - the lever moves, but no locking happens - is this a known issue? how does the lock-in-place work? are there sliding pins that come out into the holes? PO had two nails stuck in to the holes to hold the motor down - in reverse, it will ride back up out of the water

    3. side-to-side lock
    this motor is on a sailboat, and only needs to be held straight forward - the locking pin that is supposed to hold it in place is there, but the bracket to catch the pin is missing, and the front plate to support the bracket is broken a little bit - are either of those parts available here?

    Thanks! ROlf in MA

  • #2
    Originally posted by Rolf@YOP View Post
    the front plate to support the bracket is broken a little bit
    How can something be broken a little bit?
    It is either broken or not
    Sorry, I am no help on getting part.
    Just here to rib you a little bit


    • #3
      blow boat.
      means ya aint gonna spend any money on it anyway.
      wind is free, everything else outta be.

      most lilky its over heating due to the two casting passages in the cyl head.
      its way common on blow boat kickers.

      its also why I stay away from blowboaters.

      strange breed.

      but I do have a very nice tiller handle electric start blowboat kicker 25" 9.9 with a new head for sale.


      • #4
        don't think overheating because
        1. it happens immediately, cold motor
        2. when you squeeze the prime bulb, engine revs right up again
        got to be fuel pressure - check valve or lift diaphragm, right?


        • #5
          just a bit but think.
          THE ONLY thang that primer does is PRIME the fuel system.
          if you stored your car eveyninght on its grill it may need a primer.
          the primer is simply that it primes the system.
          after that it can be tossed in an epa approved blowboater approved dump site.

          I guess by now I don't like blowboaters nor like working on their POS motors
          I am sorry that most likely your 20+ yr old pumpm failed, but if it did it feed debris downstream.


          • #6
            The fuel pump can be tested, taken apart to inspect the insides, or just replaced if it is old if it is suspected as being a problem, It is you choice

            But like Rod said there can be trash in lines and pump that end up in carb if they come apart due to age


            • #7
              thanks guys, understood
              I will start w/ prime pump b/c I can feel it backwashing through the check valve when I pump
              (but I understand bulb is not supposed to stay pressurized)
              if that doesn't fix it, I understand pump may have failed, and if so likely debris in lines and carb
              no biggie, I'll work my way forward
              likely a new pump and carb clean
              thanks for the help


              • #8
                Look up under the RED section under parts.

                You should be able to find the other parts on that page, re locking down and setting the tilt adjustment...

                BTW, sounds like the fuel pump is toast if it keeps running when you keep priming (your doing the work of the fuel pump)
                Last edited by TownsendsFJR1300; 08-08-2014, 07:16 AM.
                1997 Angler 204 CC, 2006 F150 TXR


                • #9
                  yup, assuming fuel pump is toast
                  replaced the prime bulb, no change in behavior


                  • #10
                    but apparently there is no separate fuel pump on a '93 9.9 4-stroke ELHR? just an internal diaphragm or 2? (or at least the pump is integral to the carb body?)
                    looks like parts #45 and #39 are diaphragms
                    replace? what else?


                    • #11
                      gaskets and check valves


                      • #12
                        get a grip slowly.
                        the above diagram is for a TWO STROKE.
                        way way way different than a four stroke.
                        lets all get on the same parts and service page.


                        • #13
                          ok, finally back at the boat
                          popped the lid on this Yami to see what's what
                          tracing the fuel line, it leads to very small inline filter, and then the fuel pump (I assume)


                          • #14
                            no pic's posted...
                            1997 Angler 204 CC, 2006 F150 TXR


                            • #15
                              stupid Flickr
                              here again: