Regardless of the variety of Flexible-impeller pumps in support, most share many building similarities. Removing the end cover four to six screws will expose the impeller. Just about all impellers are a sliding fit on the driveshaft, possibly with splines, square keys, Woodruff keys, a couple of flats on the shaft, or a slotted shaft. If an impeller puller isn’t available, use a pair of needle nose pliers or Vies-Grips to hold the impeller and pull it out. Some impellers are sealed to their own shafts, with O-rings; many aren’t. If the impeller will not come loose, it could be among the few locked in place with a setscrew Allen twist; specifically, some Volvo Penta motors. On some of them, you can pull the impeller far enough 1/2 inch to release the twist, but when the twist is inaccessible, you need to disassemble the drive side of the impeller and knock the impeller out on its shaft.
The impeller vanes must have rounded tips not worn apartment and show no signs of swelling, distortion. Or cracking of the vanes, or any type of set bend. if in doubt, replace the impeller. When an O-ring is fitted into the shaft, check it for damage. If the impeller has a tapered metal sleeve on its internal end extended insert impellers, inspect the sleeve and discard the impeller if there is any indication of a measure where the sleeve-slides to the shaft seal.If it is necessary to remove the camera e.g., to substitute a wear Plate, loosen the camera retaining screw, tap the screw until the camera breaks loose, then remove the screw and camera Clean all surfaces of sealing compound.Some impellers have a wear plate in the back of the marine pump singapore. If fitted, the plate could be hooked out using a bit of bent wire. Notice the notch in its top; this contrasts using a dowel from the pump body. If the wear plate is grooved or scored, replace it. There are 3 types of shaft seals.
- Lip-type seals, which press into the pump casing and have a rubber lip that grips the shaft.
- Carbon-ceramic seals, where a ceramic disk with a smooth face chairs in a rubber boot in the pump casing. A spring-loaded carbon disk, plus a smooth surface, is sealed into the pump shaft with a rubber sleeve or O-ring. The spring holds the carbon disk against the ceramic disk, and the smooth faces of both provide a seal.
- An outside stuffing box packing gland, that is just like a propeller-shaft stuffing box. These aren’t very common.
Although it is possible to hook and replace some Carbon-ceramic seals with the shaft in place that can’t be accomplished with lip-type seals, typically the shaft has to be taken out. To do so, take apart the drive end of the shaft.