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Water impeller replacement-gctid801956

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    Water impeller replacement-gctid801956

    I have 2007 bayliner 245sb, what are step to inspect and replace water impeller on mercruiser 350 mpi bravo system? I cant find any youtube video on how to pull out the water pump housing?

    This might help
    2007 Discovery 246
    Mercruiser 350 MAG MPI
    Bravo III
    Puget Sound North


      That's a good how to video on the impeller replacement. He did goof when he rotated the housing against the direction of the newly installed impeller but I think it will correct itself as soon as the engine is turned over. Make sure you mark the possition of your impeller housing before removing it and make notes as to which hose goes where yes it matters! The pump shown has the intergrated fuel pump attached and the hoses will be opposite on your mpi.
      Edmonds, WA
      "THE FIX"
      '93 2556
      Carbureted 383 Vortec-Bravo II 2.0:1 18 1/4x19 P

      The rebuild of my 2556
      Misc. projects thread


        Guys My engine 350 mpi has that cool fuel filter box. How do I get around that box?


          Can't help with the Cool Fuel Filter Box question, but I will say that this job is pretty simple with the engine on a stand. Standing on your head, placing your feet perfectly, one knee on the holding tank all makes this job much more difficult. I notice the youtube video had the intake/exhaust hose marked with surveyors tape. This is a great idea, take it from somebody who switched the hoses. Removing those hoses can be troublesome. I've even had to put a foot on the hose at the rear of the engine and almost kick it free. Spin, twist, use a screw driver/pry bar to start to push it off the flange, then use brute force. I also remove the entire pump and pulley system and install the new impeller while on the work bench.
          1999 Ciera 2655 5.7L BIII "Brenda Lou"
          1996 Skeeter 1850DV 175 Mariner 9.9 Mariner. sold, sold, sold
          1975 Lund 14' 25 HP Mercury. sold, sold, sold
          2008 Dodge Ram 2500 4x4 6.7L Turbo diesel Quad Cab
          Green Bay, WI on the Fox River
          South Bay Marina


            This is about as good an explanation/video I've ever seen on this:


            These boats, with the cool fuel module make this task unbelievably difficult. I do nearly all my own maintenance, but this is one thing I pay a young, agile mechanic to do. Good luck. Someone here will chime in with replacing this pump with a crankshaft mounted pump. I considered that as well, and even went so far as purchasing the pump. For a variety of reasons, I opted out. If you go that route, and are interested in a new, unused pump still in its box give me a shout.


            This link contains further info:

            Mike & Dixi
            2006 265 5.0 MPI B3
            Closed Cooling


              Here's my procedure for my 2005 350 MAG Cool Fuel box, but I hope this helps.

              Seawater pump impeller/O-ring kit 47-862232A $35


              A> REMOVING THE PUMP

              (1) Loosen jamnut (5/8") on tensioner pulley, release tension on serpentine belt by turning adjustment stud (5/16"), and remove belt.

              (2) Remove idler pulley directly above seawater pump by removing the thru-bolt (use 5/8" wrench to hold bolt head behind pulley and a 5/8" socket for nut on pulley face). This frees a small bracket at the top of the pump brace from the alternator bracket.

              (3) Loosen clamp and disconnect the hose that connects to the bottom of the "Y" pipe next to the seawater pump pulley.

              (4) The red 1.25" I.D. seawater intake hose has a quick-disconnect fitting midway between transom connector and pump, located below cyl #6. Pry up the retainer clip with a flat-bladed screwdriver and separate the connection. (If your setup does not have this Q-D fitting, then loosen clamp on the upper hose at the pump housing and disconnect hose from pump. If necessary, the fuel-water separator filter can be removed for better access).

              (5) Loosen clamp and remove lower hose from pump.

              (6) Using a 9/16" deep socket, remove nut from mounting stud at top of pump brace. This will release the small bracket mentioned in step (2) above. Remove the 9/16" bolt directly below the stud - the pump is now free. Carefully walk the pump out and off the mounting stud. If there is still a section of the red intake hose attached, loosen clamp and remove hose from top pump port.



              (1) Using a 10mm socket, remove the 3 bolts that hold the brace to the pump (2 on the pump housing and 1 on top of the shaft behind the pulley) and separate the brace from the pump.

              (2) Remove the remaining 4 bolts with the 10mm socket, and the backplate separates from the housing.

              (3) Remove and discard the O-ring

              (4) Using 2 flat-bladed screwdrivers on opposite sides, carefully pry the old impeller up and out of the pump housing.

              (5) Thoroughly wipe clean all surfaces, including the recess for the O-ring, and inspect front housing wall and backplate for excessive wear or scoring. If okay, smear some petroleum jelly onto the housing front wall.

              (6) Take a 1/4" wide plastic ziptie and wrap it around the middle of the new impeller, getting it as tight as possible, while folding the impeller vanes down. Using a squirt of dish detergent and some water, coat the impeller to get it nice and slippery.

              (7) With the pump housing standing upright on the pulley, firmly twist the impeller counter-clockwise while pushing it down into the housing, at the same time ensuring that the impeller vanes are squeezed into the housing. As the impeller lines up with the flats on the shaft, it will slide down into the housing, and the ziptie will ride up and off. Make sure the impeller is seated all the way down into the housing.

              (8) Dab some petroleum jelly into the recess for the O-ring and press the O-ring into place. Dab PJ on backplate where it contacts impeller.

              (9) Position the backplate on top of the housing and start the 4 bolts fingertight to ensure proper alignment. Position the brace and start its 3 bolts. Tighten down all 7 bolts with the 10mm socket.

              (10) Re-attach the red inlet hose to the upper pump port and clamp securely. Pump is now ready to be re-installed, following section A in reverse order.
              2005 288 Command Bridge
              350 Mag MPI / BRAVO III

              Every Day Is Saturday