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Testing and Adjusting
325D and 329D Excavators Hydraulic System
Media Number -RENR7385-11 Publication Date -01/03/2011 Date Updated -18/03/2011
i03154380
Specifications
SMCS - 5050
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Illustration 1 g01443776
Relief valve locations
(A) Boom cylinder line (rod end)
(B) Bucket cylinder line (head end)
(C) Main relief valve
(D) Stick cylinder line (head end)
(E) Boom cylinder line (head end)
(F) Bucket cylinder line (rod end)
(G) Stick cylinder line (rod end)
(H) Swing motor
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(J) Swing (left)
(K) Swing (right)
(L) Pilot filter
(M) Pilot relief valve
(N) Travel motor (right)
(P) Right travel crossover relief valve for forward travel (upper valve)
(Q) Right travel crossover relief valve for reverse travel (lower valve)
(R) Left travel crossover relief valve for forward travel (upper valve)
(S) Left travel crossover relief valve for reverse travel (lower valve)
(T) Travel motor (left)
Table 1
Specifications
Torque for
Relief Valve New Service Locknut
Rebuilt (1) Limit (2)
33000 kPa
35000 ± 500 kPa (5075 ± 72
(4800 psi) to 70 ± 10 N·m (50
psi)
35500 kPa ± 7 lb ft)
(5150 psi)
(C) Main relief valve
33000 kPa
36000 ± 500 kPa (5220 ± 72 (4800 psi) to 50 ± 10 N·m (37
psi) (Heavy Lift (if equipped)) 35500 kPa ± 7 lb ft)
(5150 psi)
36000 kPa 20 ± 2 N·m (14 ±
(E) Boom cylinder line
38000 + 1500 - 500 kPa (5510 (5200 psi) to 1 lb ft)
(head end)
+ 220 - 73 psi) 39500 kPa
(5730 psi)
(A) Boom cylinder line
(rod end) 35000 kPa
37000 + 1500 - 500 kPa (5370 (5100 psi) to
(D) Stick cylinder line + 220 - 73 psi) 38500 kPa
(head end) (5590 psi)
(G) Stick cylinder line (rod
end) 38000 + 1500 - 500 kPa (5510 36000 kPa
+ 220 - 73 psi) (5200 psi) to
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39500 kPa
(5730 psi)
(B) Bucket cylinder line
(head end) 35000 kPa
37000 + 1500 - 500 kPa (5370 (5100 psi) to
(F) Bucket cylinder line + 220 - 73 psi) 38500 kPa
(rod end) (5590 psi)
(K) Swing relief pressure
(right) 27400 kPa
29400 ± 1000 kPa (4250 ± 145 (3970 psi) to 120 ± 10 N·m (85
(J) Swing relief pressure psi) 30400 kPa ± 7 lb ft)
(left) (4410 psi)
(R) Left travel crossover
relief valve (forward)
(S) Left travel crossover
relief valve (reverse) 34500 kPa
37500 ± 1500 kPa (5450 ± 220 (5000 psi) to 90 ± 10 N·m (70
(P) Right travel crossover psi) 39000 kPa ± 6 lb ft)
relief valve (forward) (5650 psi)
(Q) Right travel crossover
relief valve (reverse)
(M) Pilot relief valve 50 ± 5 N·m (36 ±
4100 ± 200 kPa (595 ± 29 psi)
4 lb ft)
(1) A New specification is the performance that can be expected for a new machine. A "Rebuild" specification is the
performance that can be expected after rebuilding the components of a system.
(2) Performance beyond "Service Limit" specifications is an indication of the following problems: improper adjustment ,
wear , damage of relief valves and damage of pumps.
Table 2
Required Tools
Part Number Description Qty
9U-7400 Multitach Tool Group 1
8T-0470 Thermometer group 1
Note: Normal operations of the engine and pumps are necessary for the pressure adjustments. If the
results of the pressure adjustment are not correct, then the engine and the pump characteristic curve
needs to be checked. Slow output flow from the pump is an indication of air in the hydraulic system.
Make sure that no air is present in the hydraulic system. Refer to Testing and Adjusting, "Main
Hydraulic Pump Air - Purge".
Fri Mar 29 2024 09:35:46 GMT+0700 (SE Asia Standard Time)
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