Lubrication system (Discovery 3)

General information

Oil is pumped out of the reservoir in the oil pan and supplied under pressure by the oil pump. At the outlet of the oil pump, the oil is filtered and distributed through internal oil supply channels.

Lubrication of all moving parts is carried out by supplying oil under pressure or by oil splashing. Oil under pressure also ensures the operation of hydraulic compensators and timing chain tensioners.

The engine is lubricated by a forced oil circulation system using a full-flow oil filter. The oil cooler forms a single unit with the oil filter and fuel cooler and is located in the center of the cylinder block between two rows of cylinders. Cooling of the engine oil is provided by the engine cooling system. This eliminates the need to use an additional separate oil cooler.

The fuel cooler, which is part of the oil filter housing, also uses engine coolant. In addition, there is an additional fuel cooler in the return line of the fuel tank.

Information obtained from the website [LRman.ru]

The oil returns to the sump by gravity. Large drain holes in the cylinder heads and block provide rapid oil return, reducing the volume of oil required and allowing accurate oil level readings shortly after the engine is stopped.

Oil is added to the system through the oil filler neck on the right-hand camshaft cover.

With the exception of the pump and dipstick, all parts of the lubrication system are mounted on the oil pan.

Oil collection

The cast composite oil pick-up tube is immersed in the oil reservoir and supplies oil to the oil pump in any permissible vehicle position. The crown-shaped inlet allows oil to be supplied even if the oil pan is deformed (e.g. as a result of hitting the ground). A mesh in the inlet prevents solid particles from entering the lubrication system.

Oil pump

Item name	Spare part catalog number	Description
1	-	Oil pump
2	-	Bolt

The gear type oil pump is bolted and pinned to the front of the cylinder block. The seal is provided by a rubber gasket embedded in the oil pump housing. The inlet and outlet ports of the pump are aligned with oil grooves in the ladder structure.

The working element of the pump is an eccentric rotor, driven directly by flat surfaces on the crankshaft. The built-in pressure relief valve regulates the pressure at the outlet of the oil pump, fixing it at 4.5 bar (65.25 psi).

The front crankshaft oil seal is located in the oil pump housing and is secured in such a way that its front surface is recessed by 1 mm relative to the machined front surface of the oil pump.

NOTE: The seal must not be pressed all the way into the hole as this will block the drain passages.

Oil filter

The oil filter is a replaceable cartridge mounted on an adapter in the center of the V-shaped row. An internal bypass system allows oil to be supplied around the filter if it is clogged.

NOTE: During repairs, care must be taken when removing the filter to minimize the amount of oil spilled between the V-shaped cylinder blocks and into the camshaft caps.

• Do not use compressed air/power tools
• Loosen the oil filter cap 4-5 turns.
• Wait at least 1 minute to allow the oil to drain.
• Remove the lid, trying to minimize the amount of oil spilled.
• Replace the oil filter element in the cover. (it can only be installed one way).
• Replace the cap and tighten it to the specified torque.

Oil pressure sensor

Item name	Spare part catalog number	Description
1	-	Oil pressure sensor

The oil pressure sensor, located in the V-shaped row in front of the left cylinder head, closes the instrument panel input to ground when oil pressure is present. The sensor operates in the pressure range from 0.15 to 0.41 bar (from 2.2 to 5.9 psi).

Oil dipstick

The dipstick is located centrally along the left side of the oil pan in a tube inserted into the ladder frame. The two holes at the end of the dipstick correspond to the minimum and maximum oil levels. The difference between these two marks is approximately 1 liter. (1 US quart).