The fuel pump is an important component of a car or any other engine that has an internal combustion process involved in its functioning. Engines that use gravity to channel the fuel from the tank to the engine via a hose do not require fuel tanks. But those designs that do not feed on gravity to pump the fuel into the engine require mechanical pumps that are generally mounted onto the external wall of the fuel tank to circulate it to either the carburetor or the fuel injecting system. Repairing a fuel pump may be time-consuming and difficult, but it is definitely not impossible. Here are some rules to keep in mind while undertaking a repair job.
Secondly, using sealing tapes made of Teflon in any part of the car engine should be consciously and vehemently avoided. This will cause major damage to the engine.
Thirdly, the materials required for repairing the engine of a vehicle meant to be a show car is very different from one that is meant for a driver. Therefore it is very important to decide on the purpose that the car is meant to serve before embarking on the repair job. The common problems that plague a damaged fuel pump are leaking check valves and sediment bowl gaskets, broken spring and damaged diaphragm.
Let us now discuss the method of replacing a fuel pump in a car engine meant for a driver. Before removing the flange screws, draw a line from end-to-end to mark the level and point at which they must be reassembled. Once you have dismantled and cleaned the pump thoroughly, it will be easier to access the damage and formulate the way to disconnect all actuating links that control the operating process of the diaphragm. In the case of duplex pumps where one of the diaphragms pump gas, while the other creates a vacuumed environment for the wipers to operate by pumping air, both diaphragms need to be replaced. Once these diaphragms are removed, check the underlying seals for any signs of damage.
Always ensure that the replacement kit you purchase has diaphragms composed of VITON. New check valves are contained in some kits that are used to repair pumps with removable valves. For those without removable valves, the option is to change the present seating position of the valve.
Dismantle the valve retainers and store the discs and accompanying springs and store them safely. Following this, place a 3-inch long wooden dowel within a drill press, and then place a sandpaper of medium grit on the drill-press table, with the grit facing upwards. Turn on the drill and ensure that the dowel has a smooth and even surface. Carefully attach a tiny disc of extremely fine sandpaper, either dry or wet, to one side of the dowel. Following this, slowly and gently, ensure that the sandpaper is in contact with the valve seat. Check after a few seconds to ensure that the grit is evenly distributed. If you notice dull patches, then repeat the procedure.
After this, check the discs of the valve for any damage in the area where it touches the seat, and if you spot any such points, then turn the disc onto the other side, or sand it with a fine sandpaper (600 grit) on a flat glass piece. Then, reassemble the new fiber washers and small springs.
Reinstall the pistons in their original positions by using the links. Remember to attach new seals and springs that help the pistons to operate. Check on the original marks to attach the flanges in their exact original positions.
The directions in the manual will tell you if the screws of your pump model require extra tightening. Tighten them evenly and gradually until they are completely set in position. Finally, attach the pipes for inlet and outlet by using Teflon sealants.
The last step is to replace the sediment bowl in the new gasket. Blow air into the inlet to check if it passes to the pump. Then you can use suction to check that there are no residual air bubbles in the pipe. First, the actuating arm should be operated upon manually, to check for any chattering sounds of air in the pump. If all these check steps yield positive results, then you can safely conclude that you have done a successful repair job.