LUBRICATION SYSTEM-L.S NOTE: Caution should be exercised when restart- ing the engine, as it will take a moment or two for the oil pump and pipes to prime, therefore the engine speed should be kept to a minimum until either gauge shows satisfactory pressure (where fitted) or the oil pressure warning light is ex- tinguished. LUBRICATING OIL FILTERS To ensure cleanliness of the lubricating oil a sump strainer and a main full flow type of oil filter are fitted. The sump strainer consists of a gauze wire container which is fitted over the end of the lubrication oil pump suction pipe. All oil must pass through this strainer before it reaches the oil pump.
The most satisfactory way to prime the lubricating oil system is to motor the engine for approximately 10/20 seconds with the stop control in the "no fuel" position until oil pressure is indicated before any attempt is made to start the engine. The main full flow type oil filter is mounted externally on the side of the cylinder block. All the oil passes through this filter after it leaves the pump, but before it reaches the bearings. OIL PRESSURE RELIEF VALVE The full flow filter may incorporate a paper element in a bowl or a screw on canister in which the element is an integral part of the canister.
At the appropriate time, as given on Page C.2, the paper element or the canister should be renewed as detailed below. The oil pressure relief valve is contained in a housing integral with the oil pump end cover, which is secured to the rotor housing by four setscrews. This relief valve controls the maximum oil pressure by allowing a spring loaded plunger to move and by-pass excess oil back to the sump when the pre-determined spring pressure given on page B.10 is exceeded. To Renew the Paper Filter Element 1. Unscrew the filter bowl securing setscrew as shown in Fig. L.1 O. 2. Withdraw the filter bowl (Fig. L.11), remove the element and .discard. 3.
Clean the bowl in a suitable cleaning fluid. 4. Renew the sealing ring in the filter head, where necessary. 5. Place the new element centrally in the bowl, posi- tion the bowl and element assembly squarely and centrally on the filter head and tighten the bowl securing setscrew. 6. As the filter element will normally be changed at the same time as the engine lubricating oil, refill the sump with oil, run the engine and check for oil leaks. Recheck the oil level after running the engine and top up as necessary. The filter bowl securing setscrew should be checked for tightness alter 1000 miles (1500 km) or 24 hours running following a filter element change.
To Dismantle the Oil Pressure Relief Valve 1. Drain the engine oil from the sump. 2. Remove the sump securing setscrews and carefully remove the sump. 3. Continue as for removing the oil pump as pre- viously detailed. 4. Remove suction and delivery pipes. 5. Remove the four securing setscrews and remove the end cover assembly. 6. Remove the split pin from the end of the housing and withdraw the spring cap, spring and plunger. An exploded view of the assembly is shown in Fig. L.9. 7. Thoroughly clean the parts, inspect for wear or damage and renew if necessary. To Re·Assemble the Oil Pressure Relief Valve 1. Replace the plunger, spring and spring cap then secure with the split pin. 2.
Secure to the lubricating oil pump body by means of the four setscrews. 3. Continue as detailed for refitting the lubricating oil pump. Oil PRESSURE Always ensure that with the engine running, oil pressure is registering on the gauge or the oil pressure warning light is extinguished. Pressures do vary according to climatic conditions and even between individual engines, but the oil pres- sure range at normal working speed and temperature is given on Page B.9. The pressure will drop whilst the engine is idling and also a slight drop will be ex- perienced when the oil is hot, this is quite normal.
If, however, the oil pressure is suspected of being too high or too low then reference to the possible faults listed under these headings given on Page D.1, may prove helpful. l10