Harley Davidson (1970 to 1972) Electra Glide / Super Glide. Service manual — page 3

General

OIL FILTER (Figure 3-1)

The tank is equipped with a large mouth filler opening and a screw cover with oil filter attached.
Wash filter element (3) in clean gasoline or solvent at 2,000 mile intervals, renew at 5,000 mile intervals. To service filter element, remove cap from oil tank, remove retaining spring (1) and washer (2) and pull out filter. Make certain "O" ring is positioned against filter cup flange (7) when filter is installed in tank.
SERVICING OIL TANK CAP AND FILLER OPENING

To disassemble, follow order shown in Figure 3-1. Assembly is reverse order of disassembly. Clean and inspect all parts. Replace any that are worn or damaged.

If oil leak should occur between the tank cap and the filler opening, with cap and gasket in serviceable condition, check the lip of the filler opening. A cap drawn too tight will bend the lip of the filler opening resulting in an imperfect seal between gasket and lip.

Drain oil from tank. Using a mallet as a driver and a block of wood as a cushion, bend the lip down until flush with sealing surface of tank cap. Remove nicks and rough spots with emery cloth. Flush tank before refilling.
ELECTRA-GLIDE ENGINE OILING AND BREATHER SYSTEM (The following steps are called out on Figure 3-2)

1. Gravity feed from tank to feed pump.

2. Feed (pressure) section of oil pump.

3. Check valve prevents gravity oil drainage from tank to engine. Builds up oil pressure to operate oil signal switch.

4. Oil pressure regulating valve limits maximum pressure. Surplus oil is dumped back into gear-case.

5. Oil is forced through pinion gear shaft to lubricate lower connecting rod bearings from which oil splashes to cylinder walls, piston, piston pin and main bearings.

6. Oil is forced through passages or external oil lines to lubricate rocker arm bearings and rods.

valve stems, valve springs and push rod sockets. A branch passage supplies oil to the hydraulic lifters. Oil supply is filtered through oil screen.

7. Front chain oil. Oil is bled from by-pass oil for front chain lubrication.
8. Oil drains from cylinder rocker housing through passage in each cylinder, then flows through hole in the base of each cylinder, lubricating cylinder walls, piston, piston rings and main bearings.

9. Oil flows from the rocker arm bearings through push rod covers into the gearcase compartment, lubricating push rods and tappets.

10. Rotary breather valve is timed to open on the downward stroke of pistons, allowing crankcase exhaust air pressure to expel scavenge oil from crankcase breather oil trap into gearcase. Breather valve closes on upward stroke of pistons, creating vacuum in crankcase.

During this interval, the small ports in breather valve line up with passage in crankcase. Oil is then retrieved through passage by vacuum from breather oil trap in crankcase.

11. Oil blown and drained into timing gearcase (steps 4, 8 and 9), lubricates timing gears and gear shaft bearings.

12. Gearcase oil settles in gearcase sump from where it returns to pump.

13. Scavenge (return) section of oil pump.

14. Engine oil return to tank.

15. Exhaust air baffle and transfer passage to breather oil trap.

16. Breather oil trap.

17. Oil transfer passage to breather valve.

18. Crankcase exhaust air escapes from gearcase through outside breather tube.

19. Return line from chain housing.

20. Vent line to oil tank and chain housing.

21. Rear chain oiler.

22. Pressure switch fitting.

REPAIR PROCEDURE

GENERAL

When an engine needs repair, it is not always possible to definitely determine beforehand whether the