The Emergency Rescue Boats Water Cannon Motor and Pump for the Front Water Cannon, is a combined part, and are accessed under the top deck. To remove the Top Deck, start with removing the rear helipad deck cover, by pulling it up and away. Secured in four corners with pressure posts made to withstand your pulling it up and away. Or a flat screwdriver and slip it under the four corners and give it a twist until they are all loose, then pull it up and away. Now you have access to the 13 screws holding the upper deck to the hull. When removed, you can carefully lift the upper deck from the hull.
The Wiring Harness for the Water Cannons Motor has a plug-in connector for the ESC/Receiver board, no soldering is required, just plug and play. To remove the Water Cannons Motor and Pump connection to the ESC/Receiver board, you must remove the two screws holding the ESC cover box from the upper deck. You will also have to carefully remove the Silicone Caulking/Glue from the hole in the ESC cover box and from the wires passing through that hole. Carefully scrape and pull the caulking away, until you can move the cover box out of the way, and unplug the Water Cannon Motor from the ESC/Receiver board. Then manipulate the wiring harnesses to get the correct one to the side with the larger hole in the cover box, and slide the harness connector out of the cover box.
To Remove the Water Cannon Motor and Pump from its mount, you need to remove the two screws from the securing Bracket and lift it out of the way. Now you need to remove the water lines from the Hull and the Water Cannon, and you can remove the whole part to replace them. Reverse this sequence to replace. Don't forget to caulk the hole in the cover box with a silicone caulking to seal it up.
The connections of the water hose to the Hull of the boat and the Water Cannon must be tight or water pressure from the pump may blow it off. If it is difficult to press the hoses on, moisten the ends with a bit of water. If it still seems too tight to get on, try a little slightly soapy dishwater on the hose ends. When they are on, make sure you let those hose connections thoroughly dry, especially if you used dish soap.