Replacing the excavator Oil Pump,many people simply place orders based on the excavator tonnage,often resulting in incorrect installation hole positions,inconsistent driving methods,inconsistent pressure limiting valve parameters,and interference with the oil port position,making it impossible to install and use after purchase.The oil pump is a precision matching accessory,and selection requires confirmation of key information such as engine model,drive form,oil pump part number,limiting pressure,interface size,etc.It cannot be purchased solely based on appearance similarity.

　　Firstly,determine the corresponding complete engine model.Excavators of the same tonnage,equipped with different engines from different factory batches,make the oil pump completely incompatible.For example,for the same 20 ton excavator,some are equipped with imported engines,while others are equipped with domestic substitute engines.The appearance of the oil pump looks similar,but the internal rotor gears,mounting holes,and drive shaft dimensions are all different.Prioritizing the search for the original OE part number and providing it to the accessory supplier is the most reliable way to select.When the old parts are still present,the part number of the old oil pump body can be directly copied and engraved.

　　Secondly,distinguish the driving mode.There are two common types of oil pumps:crankshaft direct drive and gear drive.The internal keyway and flat mouth size of the oil pump driven by the crankshaft must be perfectly matched with the crankshaft;The gear drive model needs to confirm the modulus and number of teeth of the driving gear.The drive structure deviates,either unable to be installed or unable to rotate after installation,completely unable to establish oil pressure.

　　Furthermore,confirm the set pressure of the pressure limiting valve.Different engines require different oil system pressure relief.If the pressure limit of the replacement oil pump does not meet the original factory standard and the pressure is too high,it will damage the oil seal and cause a large amount of oil leakage;The pressure is too low,and the lubrication oil supply of the whole machine is insufficient,resulting in bearing wear.When purchasing auxiliary factory oil pumps,it is necessary to confirm that the parameters of the pressure limiting valve are consistent with those of the original factory and cannot be mixed arbitrarily.

　　Simultaneously check the direction of oil inlet and outlet,the position of fixed screw holes,and the sealing surface of gaskets.The appearance of some oil pumps is almost identical,the oil port angle is offset,and the loading pipeline interferes.When purchasing online or in bulk,it is best to take multi angle photos of the old parts and check them together with the measured dimensions.Priority should be given to selecting original or first-line brand oil pumps for new machines and high-frequency construction sites;Reliable spare parts can be used for old equipment,and low-priced and low-quality refurbished oil pumps should be avoided resolutely.The selection of oil pump cannot be compromised,as inadequate adaptation will directly threaten the safety of the entire engine.