A minor boat repair often includes repairing paint chips, repainting some parts of the boat, or fixing your speedometer. Fixing your speedometer is a minor repair. However, if not immediately fixed, your boat can be in for a lot more trouble than you can imagine. When checking for the cause of the malfunction, you need to locate the tube of the speedometer. Once you have located the tube of the speedometer, check to see if there are any holes on the tube that might cause the speedometer to malfunction. If the tube of your speedometer is connected to the pitot tube, remove the tube from the speedometer by unscrewing the connector on the pitot tube.