When repairing an engine, it is standard practice to remove the pistons from the connecting rods. This manipulation is done in different ways, depending on the format of the piston design. There are several types of pistons in total. The processes for working with each of the varieties are described below.
Floating pin piston
First you need to remove the retaining rings from the grooves. To do this, you have to wind a sharpened tool under the ring, carefully pry it off and remove it from the groove. Next, you need to slightly move the piston pin so that it does not interfere with the exit of the ring. Be sure to hold it with your finger to prevent the ring from slipping off. It will be great if the piston and connecting rod stick to the weight.
Piston with pressed-in pin
If the piston is motionlessly seated in the connecting rod, then it will be necessary to engage in pressing it out on the press with a jack or drive. To do this, you need to use special pads, and its radius should be slightly larger, about 1-5 millimeters, of the radius of the cylinder, otherwise a breakdown may occur. You need to press out the finger with a stepped mandrel with a centering belt. It will need to be placed in the hole of the pin, while the outer diameter should not be less than the pin.
Pistons from American engines
These types of pistons have a cooler that extends downward. In this case, the use of a radial pad can provoke a skew and subsequent piston breakage. It is necessary to install another pad, or use a flat pad with a hole that can support the piston on the refrigerator. A stepped mandrel can be used to remove the pin. With its help, you can gently knock your finger out of the hole, while holding the piston in weight.
Dismantling the oil pump
When complex vehicle and / or engine repairs are performed, the oil pump needs to be disassembled. This will allow not only to remove dirt that accumulates in the channels of the body, but also to assess the condition of the gears and the body, as well as determine the clearances in the parts and examine the pressure relief valve for its functionality. This will ensure a quality car repair.
The design of the pump does not affect its components; it always consists of a housing with gears and a cover. To disassemble it, you just need to unscrew the bolts and remove the cover from the case. Sometimes the cover can be secured with screws (if the gear pump is driven from the front of the crankshaft). In this case, you will have to use an impact screwdriver, but with great care so as not to damage the case.
It is very rare to find the design of an oil pump marked "TOYOTA", which is not possible to disassemble on your own due to the drive gear, which, together with the main pump gear, are pressed onto the roller on both sides. In this case, you will have to control the condition of the parts without disassembling the unit. If defects are found in such a pump, you need to completely change the part or use non-standard methods - for example, drill a roller.
It will not be difficult to disassemble the pressure reducing valve, even for an inexperienced car owner, but it is worth remembering that it is not always located in the pump housing. Sometimes it can be on the oil filter adapter located on the cylinder block.
