Turn your Navigator/Pool Vac Ultra pool cleaner over and look at the cleaner's shoes. The picture at left shows an example of badly worn shoes. When the shoe is pushed up against the end of the pod, the shoe should extend above the surface of the pod or the pod will start to rub against the pool floor. This shoe should have been replaced before the surface of the shoe had worn below the surface of the pod.
Next inspect the Navigator/Pool Vac Ultra's wings for wear and cracks. There is a wear line on each of the wings. When you can no longer see this line, replace the wings. The picture at left shows an example of a badly worn and broken wing. At 1, the wing has worn through by the peg that holds it in. At 2, the hole in the wing has worn to the point of breaking. Not shown - the tip of the wing has worn beyond its replacement line.
When replacing Navigator/Pool Vac Ultra parts, consider purchasing a pool cleaner tune-up kit. If one set of parts requires replacement, it's probably a good time to replace all of these parts. This kit includes a set of 4 shoes, a set of 2 wings, a set of 2 flaps (front and rear) and a screwdriver and brush to install the parts. When you purchase this kit, check to make sure you purchase the kit with the correct shoes. Shoes for concrete or gunite pools are different than shoes for fiberglass of vinyl pools.
Next dip a new shoe in the water for lubrication and press it onto the holes in the pod. Note, the two plugs on the shoe fit into two different size holes, one bigger that the other. This ensures that the shoes are properly attached. Press until you feel it snap into place. Repeat for the other three shoes.
Replace the pod plug and tap then into place with the screwdriver handle. Repeat this process for the other wing.
Note that the new flaps are marked "Rear" and "Front". Make sure to install the proper flap in the front and real of the unit. The rear of the unit has the screen in it. When installing the front flap, be sure that the extended leg of the spring is inserted into the notch on the front of the lower body. Push the flap in place so that the pivot nibs engage the pivot holes in the body. Fold the flap in towards the bottom of the cleaner. There will be some resistance until the flap snap into place. Check that the spring is in place and that the spring action works freely.
Turn the Navigator/Pool Vac Ultra right side up and look at the lower left side of the unit. Look for the blue rear flap adjuster, a round knob about the size of a pencil eraser with an arrow slot. You will see the Roman numerals I, II and II around the adjuster. With a screwdriver turn the slot so that its arrow points to the II. This is the normal operation level for the cleaner. I setting slows the Navigator/Pool Vac Ultra down if it's climbing the walls or sticking in corners; III setting speeds the Navigator/Pool Vac Ultra up if it can't climb the slopes.