SPACER 2686937 - Caterpillar

Illustration 5 g01267269
Pump element as
(8A) Piston
(8B) Return spring
(10) Check valve
Illustration 6 g01267295
Suction phase
(8A) Piston
(8B) Return spring
(10) Check valve
(11) Eccentric shaft
Illustration 7 g01267311
Delivery phase
(8A) Piston
(8B) Return spring
(10) Check valve
(11) Eccentric shaft
Illustration 8 g01267319
Hydraulic diagram of the pump
(7) Lubricant reservoir
(8) Pump element as
(9) Pressure relief valve
(10) Check valve
(12) Autolube pump motor The chassis ECM energizes the autolube relay about 10 minutes after the machine starts. Current is supplied to the autolube pump unit. The autolube solenoid valve is energized. The solenoid valve activates autolube pump motor (12). Autolube pump motor (12) is an electric motor which drives pump element as (8). Pump element as (8) dispenses lubricant through the lubrication distribution valve assemblies to the bearings. During the lubrication cycle, autolube pump motor (12) drives eccentric shaft (11). Eccentric shaft ( 11) drives piston (8A) of pump element as (8). As eccentric shaft (11) rotates toward piston (8A), piston (8A) is pushed in. Return spring (8B) is compressed as piston (8A) moves in. Piston (8A) opens check valve (10) which dispenses lubricant through the lubrication distribution valve assemblies to the bearings. As eccentric shaft (11) rotates away from piston (8A), return spring (8B) expands. The expansion of return spring (8B) keeps piston (8A) in contact with eccentric shaft (11) which closes check valve (10). As check valve (10) closes, lubricant is sucked into the discharge chamber from lubricant reservoir (7) through ports in the body of pump element as (8). The reciprocating motion of piston (8A) continues until the autolube relay is de-energized.The chassis ECM energizes the autolube relay at specified time intervals. At every 60 minute interval, the chassis ECM will turn on the autolube relay which will stay on for a specified time. When the time is up, the chassis ECM de-energizes the autolube relay. The autolube solenoid valve de-energizes which deactivates autolube pump motor (12). Then, pump element as (8) stops dispensing lubricant through the lubrication distribution valve assemblies to the bearings. The chassis ECM restarts the lubrication cycle when the next 60 minute interval begins. Then, the whole process repeats and continues until the machine is turned off.Note: In the case of a blockage in the system, the grease pushes out fault indicator pin (9A) at pressure relief valve (9) which indicates excessive system pressure. Pressure relief valve (9) is set at 27600 1400 kPa (4000 200 psi). Pressure relief valve (9) is not adjustable.For information on the electrical system, refer to Schematic, "Electrical System".Lubrication Distribution Valve Assemblies
The inlet port is connected to all piston chambers at all times. Only one piston is free to move at any one time.Stage 1
Illustration 9 g01269203With all of the pistons at the far right, lubricant from the inlet port flows against the right end of piston "A".Stage 2
Illustration 10 g01269244Lubricant flow shifts piston "A" from right to left which dispenses lubricant through connecting passages to outlet port "2". Flow is then directed against the right side of piston "B".Stage 3
Illustration 11 g01269249Piston "B" shifts from right to left dispensing lubricant through outlet port "7".