by Wallace Marine Services, Inc. Maintain Your Equipment The Easy Way Bill Wallace 843-693-4336 info@willyvac.com www.willyvac.com Pump Replacement Manual 1
How to change the water pump on the Willy Vac Horizontal Model NOTE: Please read through this manual before you begin; then follow it as you work. There are a series of steps to performing this task. Failure to follow the procedure as I have laid out can result in a damaged machine. So Don t Break it! Your Willy Vac was not built to stand up to a hard blow or a lot of force, so pay close attention to this manual and the photos illustrating where to pry. Don t beat on it! Don t cuss it! Step 1. Remove the Machine from the boat. Drain the water and remove the machine from the boat. Set the lid and strainer basket to the side. You will be working on the machine while it is upside down. Because of this, you may want to rinse the machine out and place some towels under it to soak up the water that will drip out while you re working. The towels also act as a cushion. Step 2. Remove the U-tube. Figure 1 shows the U-tube molded into the sump assembly. If your machine has the U-tube molded in, you do not need to worry about removing the U-tube, and you can move onto Step 4. Figure 1: U-tube Molded into Sump Assembly Where to pry is VERY important. There are bulkheads inside the machine that give strength to prevent the force of the pry bar from cracking the housing. 2 Willy Vac Pump Replacement Manual
Figure 2 shows where to pry and where not to pry. If you pry in the wrong spot, you will most likely crack it. So don t crack it! Figure 2: Where to Pry/Not Pry X Do Not Pry OK to Pry X Do Not Pry OK to Pry The U-tube is held on and sealed with marine silicone. Simply pry the U-tube straight up by resting the pry bar on the machine and the flat blade of your pry bar under the lip of the elbow. Pry one end at the time starting with the left side (the end that is closest to the lid). Figure 3 shows where to pry on the lid end. A long flat head screwdriver will work for your pry bar. Put some masking tape on the machine to prevent it from getting scratched during this process. Figure 3: Where to Pry on the Lid End Willy Vac Pump Replacement Manual 3
Apply fairly strong pressure on the U-tube and hold in this position for a few seconds; you will feel the silicone break free. Once the left side has broken free for the most part, move to the right side (ball valve end) and pry up there. You may need to use a small spacer of some kind under the pry bar/screw driver to allow you the proper angle to get the U-tube pried up. NOTE: On both ends of the U-tube, you will be prying on the left sides only! Figure 4 shows where to pry on the ball valve end. Figure 4: Where to Pry on the Ball Valve End Step 3. Cut the pump wires. You can cut the wires about two inches from the top of the pump for now, then move to Step 4. 4 Willy Vac Pump Replacement Manual
Step 4. Remove the bottom to gain access to the pump. NOTE: This part will be easier with a helper to hold the machine steady while you work your magic. Figure 5 shows the bottom pump puller. Figure 5: Bottom Pump Puller Pay close attention to how to use the press and only use the press to pull out the bottom. Do not pry on any of this. Details are below. With the machine upside down, have the helper hold the machine steady while you remove the six screws that are holding the bottom in place. You may have some screws going straight through the bottom plate and into the bottom of the pump; if you see these, remove them as well. Using a razor knife, remove the silicone from between the bottom and the side of the pump bottom boss. Remove as much silicone as you can because when you go to press out the bottom, it will have to pass by the silicone, which has a tendency to cause the bottom to jam as it is trying to pass. You will ruin the bottom trying to remove it, so a new bottom has been provided with your pump. Willy Vac Pump Replacement Manual 5
Figure 6 shows how to set up the six inch diameter pipe, board and screws supplied with your pump to act as a press, press out the bottom keeping equal pressure on all the screws. Figure 6: Six-Inch Diameter Pump Take your time! Do not beat on it! After the bottom starts to move, you may notice it stops or gets very difficult to continue to move. When this happens, remove the press and push the bottom back down and clean off more of the silicone. You may need to clean the silicone a couple of times until you get the bottom all the way out. Did I mention to take your time? Now that you have the bottom out, pay attention to how thick the bottom is. Various models have various pump heights. I am not sure of your pump height, so I have sent enough precut pieces for you to put back what came out. Step 5. Gently Remove the pump Remove the three screws from the debris screen from the bottom of the pump and then remove the screen, this will make it easier to grab the pump and pull it out. It is a tight fit and will take some manipulating it to get it out. It went in, so it will come out. You may need to clean some more of the silicone from the inside of the boss to make room for the pump. NOTE: The Pump is the same diameter as the inside of the bottom boss so if there is much silicone the pump is not coming out. Important: The boss is glued in place and can be knocked out pretty easy if you get to jerking and yanking on the pump. The pump is pretty heavy so the inertia of the pump created by you yanking on it can easily break the boss free from the housing. 6 Willy Vac Pump Replacement Manual
So don t break it! Easy does it. Step 6. Clean the sensors. Now that you can easily access them, clean off the face of the sensors inside the machine. Step 7. Replace the new wire keeper with the old one. Where the wire comes out of the top of the pump, you will notice a stainless steel keeper. This keeper may have been ground down on your old pump to allow for it to pass through the hole in the top of the machine, you will need to swap out these keepers or the pump will not go all the way in. Step 8. Swap the black neoprene gasket. Your old pump may have a black neoprene gasket about ¾-inch thick on the top. If it does, put it on the new pump. If it doesn t, don t worry; carry on. The gasket may be glued on so use a little care when trying to remove it so you don t rip it. Step 9. Finish removing the rest of the water. Tilt the machine to remove the remaining amounts of water from inside and dry out the best you can. This step is important because as you reseal the machine, you will have wet silicone on the top and bottom, so whatever way you roll the machine, you could be getting water to your wet silicone and prevent it from curing properly. This will cause it to leak. Step 10. Build your new bottom. You can use the round section of pipe you used for the press to put your bottom plate and shims (if used) in and screw them together. This will insure that they as an assembly will go into the housing when the time comes. Build your new bottom to match the thickness of what came out. You can screw some short screws from the top to hold them together but be sure a ¾ inch thick piece is the most bottom piece. Step 11. Install the new pump. Put a generous amount of silicone around the center of the pump top where the power wire comes out just below the stainless keeper and also around the area where the water comes out of the pump. Then gently slide the pump into place. There should be enough wire on the pump to feed the wire into the hole of the machine first; then use the wire to pull the pump and align it into place. Willy Vac Pump Replacement Manual 7
Step 12. Install and seal in the bottom. cc NOTICE! PLEASE READ THE NEXT PART BEFORE YOU GO OFF ON A TANGENT! With all the pieces assembled to make the proper bottom thickness, insert the bottom in place (making sure that the thinner piece is toward the pump), holding firm pressure pressing the bottom plate against the bottom of the pump. Wake up your helper and get him or her to screw in the six screws you took out that held the bottom in place. NOTE: Before you put the six screws back in, be sure and squirt silicone in the holes prior to the screws. Do not tighten these screws tight; do not use a drill gun! They just need to go in until they touch the counter sink seat. Run these screws in by hand. If you tighten them, you will distort the boss, then you will crack it! So don t crack it! Using a generous amount of silicone, seal the bottom plate in place. Step 13. Seal the top section of the housing. Turn the machine right side up and using silicone, use silicone to fill in the void around the water pump outlet. Keep in mind that this silicone is sealing the vacuum so don t be stingy with it. Use plenty of silicone. Step 14. Inspect the U-tube. Look inside the U-tube and be sure nothing is preventing a good water flow. Black electrical tape is wrapped around some smaller pieces of pipe to act as a spacer to joint them to larger pieces of pipe during the building of this tube. Sometimes the tape moves over time and causes a blockage. If you see a blockage, use an X-acto knife and needle nose pliers to remove the black tape. The U-tube has a check valve inside of it, so be sure you are putting the U-tube on allowing for flow to go from the pump to the ball valve. Step 15. Seal the U-tube. Make sure the U-tube is clean and dry, then apply silicone to the top of the white fitting on the pump. Using your finger or the like, spread the silicone evenly around and down the fitting. Now spread silicone on the ball valve end of the U-tube. Keep in mind that you don t want the silicone to cause a water flow issue either. 8 Willy Vac Pump Replacement Manual
Install the U-tube, pressing it into place, The U-tube will be pressing on the wires coming out of the pump so use good judgment on how much you are stressing out the wire. Wipe off the excess silicone and let it dry overnight. Step 16. Rewire the pump. Using the supplied electrical connectors, connect the wires together matching the colors. Step 17. Replace the unit back in the boat and let r EAT! Willy Vac Pump Replacement Manual 9
by Wallace Marine Services, Inc.