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    First time prop removal-gctid406518

    After five years of running I have finally gotten into some rocks and bent up the props. Any suggestions on prop removal would be greatly appreciated. A puller and 500# air impact wrench has had little or no affect. One big plus is that I keep my boat on a lift so there is full access to the props from the walk around under the cradle. The boat is a 1986 3870 with 175hp Hinos. Luckily I carry a set of spares so my down time will be minimal once I wrestle them off.

    #2
    Try tensioning the puller and then whack it with a hammer. That sometimes works. When you reinstall grease the shaft first.

    Hope this helps.

    Tom
    Tom Brooke
    MV Overexposure - 1999 4087
    MMSI - 367585640

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      #3
      The firts time I removed the props on my 4087, I had to use a hydraulic unit. It has a small "hockey puck" type adapter that fits between the end of the shaft and an adapter which connects to the prop. My pullers just could not produce enough force. Many times a sharp whack will remove a stubborn prop, but I tend to avoid this, as I do not want to damage the transmission bearings. It doesn't take much of a brinell a bearing race. See number 1 on http://web.applied.com/site.cfm/Caus...ingFailure.cfm.

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        #4
        P.s. Sometimes the rudders have to come out. Lack of clearance..

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          #5
          Heat might be be necessary.

          Keep a nut on the shaft, backed off a few full turns. Put the other nut on, so it is fully engaged and its outboard face is flush with the end of the prop shaft. Put the puller back on and apply lots of pressure. Using oxy-acetylene, thoroughly warm the prop hub. Place a block of hardwood on the nut/shaft Or the puller and give the wood a good wack with a heavy sledge.

          The prop will pop off. The noise will scare you, then you'll smile.

          Comment


            #6
            Thanks Tom and Mike for the input. Time to get a bigger hammer and give it a shot (quite literally). It will be interesting to see how my replacement props perform. The replacements are 20x22 and the props on the boat are stamped 20x19.7 so they were probably "tweeked" by the PO who owned a marina. Makes me wonder what other owners are running.

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              #7
              Helped a friend remove props from a 4387 a few years ago. They had been on for many years in warmer salt water and were very stubborn. We took the rudders off as well since they needed repaired/replaced and that gave some working room. Utimately it took lots of heat from a oxy/ acetlene torch a puller and a 16 lb slegde hammer. we had the props to a dull red glow out from the hub about 6". I believe they were 22 x22's. When they popped off it had quite a bang.

              Comment


                #8
                20x22 may be more pitch than you want. I am running19x20 with 200hp YANMARS. I could use more prop but am happy with performance now.You don't want to be over proped.My boat is a 1985 3870.

                Comment


                  #9
                  HAPPY wrote:
                  After five years of running I have finally gotten into some rocks and bent up the props. Any suggestions on prop removal would be greatly appreciated. A puller and 500# air impact wrench has had little or no affect. One big plus is that I keep my boat on a lift so there is full access to the props from the walk around under the cradle. The boat is a 1986 3870 with 175hp Hinos. Luckily I carry a set of spares so my down time will be minimal once I wrestle them off.
                  I did this last week for the first time and had never seen it done. I rented the puller at the yard, and of course, no direction was provided. Not sure if this is the standard design tool available or not. So I'm using it like a gear puller and keeping both sides parallel to each other and turning the top nut (on threaded rod). No open flame is allowed in this facility, but hadn't thought of applying a torch. There are hammer marks on the tool so I start pounding, and it takes a while, but the first prop comes off. Go to do the second and it's harder yet.

                  So I'm pounding when the ever friendly yard foreman (who has a reputation) comes over and says' 'If you're going to pound on it, you need to buy your own', to which I felt like saying 'if you're going to rent tools to DIY types, you might have some sort of directions available'. The tool is 1" think steel so no chance for harm.

                  He directs me to put the nut back on as others have stated, but to run the lower nut all the way out of the way to the left and reinstall the tool. So when tightening the upper nut the two pieces no longer are parallel as shown in the lower drawing. You then turn the lower nut to drive the right piece in a direction to make the pieces parallel, and in effect have a fulcrum affect on the shaft end. I did this and it popped immediately.

                  QUESTION TO THE VETERANS: Is this is a little trick to use or is actually the standard way I should have been doing it from the beginning (not keeping the sides of the tool parallel)?


                  Comment


                    #10
                    I had the same problem the first time I removed my props. I borrowed a similar tool from a local shop and with a little pounding the props came off. Did not have to remove the rudders. Being creative, I went home and made my own tool with two pieces of channel iron, two pieces of threaded stock and 6 nuts. It's not as pretty as the store bought tool but it works!
                    Two C's 1990 3888 MY, 175 Hinos, Hurth 630 Trannys
                    Past Commodore Emerald Rose Yacht Club
                    Member International Order of the Blue Gavel
                    MMSI: 338030604

                    Comment


                      #11
                      Tombro wrote:
                      Try tensioning the puller and then whack it with a hammer. That sometimes works. When you reinstall grease the shaft first.

                      Hope this helps.

                      Tom
                      I get conflicting opinions on if the prop should go back on dry or with some sort of lubricant on the shaft. Most engineers I've talked to say it should be dry as any lubricant will eventually be forced out and you will end up with the prop loose on the shaft, which is not good.

                      I can't argue the logic, but I used a very thin film of marine grade "never seize" on mine. I check the prop nuts each year on haul out and they remain tight, so I assume the props are still tight.

                      Comment


                        #12
                        whiskywizard wrote:
                        The prop will pop off. The noise will scare you, then you'll smile.
                        When I was stationed on the USS ABRAHAM LINCOLN, divers were sent up to change two of our wheels (23' diameter down to 21') and they actually used explosives to free them. They then floated them up on airbags to a crane. Hopefully a hammer will be all the shock yours need.
                        Custom CNC Design And Dash Panels

                        iBoatNW

                        1980 CHB Europa 42 Trawler- "Honey Badger"

                        Comment


                          #13
                          Michigan wheel says never heat the props, I only use a slight amount of heat from a propane torch.

                          Any type of antisize that has metal in it such as aluminum and copper tale up a few thousands of an inch between the prop and shaft, that can be over time squeezed while running and cause a slightly loose shaft, michigan wheek says clean and re-install dry.

                          The best prop puller on the market is an Algonquin puller, the design has much mor leverage than the design pictured in this thread, I have never had to use a hammer on a prop using one of the Algonquin pullers, I believe they are no longer made, but can be found on the internet sometimes.
                          Pat says: DO-IT-RIGHT THE FIRST TIME!

                          Bayliner 3870 "ALASKA33)
                          Twin 350 GM power
                          Located in Seward, AK
                          Retired marine surveyor

                          Comment


                            #14
                            I was helping a friend pull off his props. He was having a problem, So we had installed a industrial prop puller and was tightening the nut on the fine thread puller with a air impact. We got it good and tight and smacked it (shocked it) with a hammer and it came off. We did the same thing on the starboard side but would not work, then we added heat from a acetylene brazing torch not the greatest for heating. It got hot (but not as good as a oxy/ acetylene torch. ) still no luck. So I installed a hydraulic cylinder with a 3/4 or 1/2 plate can't remember and the cylinder bent the plate. A colleague then loan my friend a Harmonic puller. This is like a hex piece of bronze around 8 " long with the same thread count as the shaft with internal threads. I think 7/8 -14. He informed me he screwed this unit on the shaft, tapped it with a hammer and the Harmonic Frequency some how loses the Morris Tapper and the prop just pops off. Amazing . So now I have also added a Harmonic Puller to my collection.

                            Has any one else used a Harmonic Puller?
                            1987 3270MY, 135 Hino engines

                            2015 Element ( Lime Green) Limited Edition 75 HP Mercury.

                            Roger, Lake Saint Clair, Michigan
                            Fair Winds & Following Seas

                            Comment


                              #15
                              purrfecto wrote:
                              20x22 may be more pitch than you want. I am running19x20 with 200hp YANMARS. I could use more prop but am happy with performance now.You don't want to be over proped.My boat is a 1985 3870.
                              Gear ratios are a governing factor, as well as engine max RPM.
                              Pat says: DO-IT-RIGHT THE FIRST TIME!

                              Bayliner 3870 "ALASKA33)
                              Twin 350 GM power
                              Located in Seward, AK
                              Retired marine surveyor

                              Comment

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