Jacobsen HR 5111, Service And Repair Instructions

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HYDRAULICS
SECTION 8B. FAILURE ANALYSIS
8B-3
8B
PROBLEM PROBABLE CAUSE REMEDY
5. Front mower will not a. Valve detent spool sticks. a. Repair (Section 8H).
lower.
b. Restriction in oil return line. b. Test (Section 8R).
6. Mower stops lowering a. Detent spool not locking in a. Repair (Section 8H).
when handle is released. detent position.
7. Mowers will not raise. a. Engine RPM must be 2000 or a. Increase engine RPM to 2000.
greater.
b. Cylinder leaking internally. b. Test (Section 8R).
c. Faulty lift valve main relief. c. Test (Section 8R).
d. Insufficient oil supply, priority d. Test (Section 8R).
valve.
e. Faulty pump. e. Test (Section 8R).
8. Mower(s) will stay in a. Cylinder leaking internally. a. Repair (Section 8L).
the raised position when
b. Valve detent poppet not seating b. Repair (Section 8H).
control handle is released.
or leaking.
c. Detent spool not retracting c. Repair (Section 8H).
completely, sticking.
9. Mower(s) slowly lower by a. Cylinder leaking internally. a. Repair (Section 8L).
themselves.
b. Valve detent poppet not seating b. Repair (Section 8H).
or leaking.
c. Detent spool not retracting c. Repair (Section 8H).
completely, sticking.
10. Mower(s) do not float. a. Valve plunger not holding a. Repair (Section 8H).
detent spool.
b. Valve detent spool sticking, not b. Repair (Section 8H).
going into detent.
c. Valve detent plunger spring c. Repair (Section 8H).
broken.
d. Valve detent plunger worn out. d. Repair (Section 8H).
11. Mowers down pressure a. Adjust flotation control. a. See Operator’s Manual.
too heavy or too tight.
12. Mower lowers hard (fast), a. Flotation control set heavy. a. See Operator’s Manual.
raises slow.
IMPLEMENT SYSTEM
1. Front mower runs slow. a. Engine RPM too low. a. Increase engine RPM.
Push manual override: b. Faulty motor control valve. b. Test (Section 8R).
Mowers still run slow, c. Faulty relief valve. c. Test (Section 8R).
see a, c and d.
d. Faulty pump section. d. Test (Section 8R).
Mowers run normal,
see b.
2. Right wing runs slow. a. Reel-to-bedknife too tight. a. Adjust (Section 12E).
b. Faulty reel or drive. b. Repair (Section 12D).
c. Faulty reel motor. c. Test (Section 8R).