Manitowoc 2250 Service And Maintenance Manual

Reference Only
Manitowoc Published 11-06-15, Control # 040-13 2-19
2250 SERVICE/MAINTENANCE MANUAL HYDRAULIC AND AIR SYSTEMS
2
12. Perform the following procedures:
a. Engine throttle adjustment (MCC Electrician). Do
not perform remaining procedures until engine
throttle is adjusted to proper speeds:
b. 950 – 1,000 RPM low idle
c. 2,100 – 2,125 RPM high idle
d. Fan and pilot pressure adjustment
e. Charge pressure checks
13. With engine at low idle, extend and retract all cylinders
(jacking, boom butt handling, gantry) three times.
14. With engine running at low idle, slowly cycle each crane
function in both directions for at least five minutes to vent
any remaining air from hydraulic system.
15. Be sure all crane functions operate in proper direction
with relation to control handle movement.
16. Check for hydraulic leaks, and correct cause if found.
17. Stop engine and fill hydraulic tank to proper level.
NOTE: MCC Assembly Personnel — pressures and
speeds noted in the remaining procedures and any
adjustments you make to correct them must be
recorded in appropriate Quality Verification Form
for crane you are working on.
Controls Calibration
1. Calibrate pressure transducers, if not already done.
2. Start and run the engine at high idle.
3. Depress and hold swing holding brake switch (on swing
handle) for one minute.
4. Repeat steps 2
and 3 a second time.
Fan and Pilot Pressure Adjustment
1. Stop the engine.
2. If crane has cold weather option, disconnect electric
plug from fan bypass valve (Figure 2-22) before starting.
3. Connect accurate hydraulic pressure gauges to gauge
couplers, as follows:
a. 0 to 5,000 psi (0 to 345 bar) at fan relief valve
(Figure 2-22
).
b. 0 to 1,000 psi (0 to 69 bar) at pilot pressure relief
valve (Figure 2-23
).
4. Remove adjusting screw from both valves. Then
reinstall them approximately 1/4 in (6 mm).
5. Start the engine.
6. With engine running at low idle, turn fan relief valve
adjusting screw (Figure 2-22
) in until gauge reads
approximately 1,000 psi (69 bar).
7. With engine running at high idle, turn pilot pressure relief
valve adjusting screw (Figure 2-23
) in until gauge reads
325 to 375 psi (22,4 to 25,8 bar). Hold adjusting screw in
position and securely tighten lock nut.
8. With engine running at high idle, adjust fan relief valve:
a. Slowly turn adjusting screw out to decrease
pressure until fans start to slow down and pressure
starts to drop on gauge.
b. Slowly turn adjusting screw in. Fan speed and
pressure will increase.
c. Continue to slowly turn adjusting screw in until
pressure stops increasing. Then turn adjusting
screw in an additional 1/2 turn.
Fan pressure should be 900 to 1,700 psi (62 to 117
bar).
If pressure is okay, hold adjusting screw in position
and securely tighten lock nut.
If pressure is not okay, determine cause and
correct.
9. Stop the engine.
10. Remove gauges and install protective caps over
adjusting screws and gauge couplers.
11. If crane has cold weather option, connect electric plug to
fan bypass valve (Figure 2-22
).
Charge Pressure Checks
Check charge pressure for load drums, boom hoist, luffing
hoist, swing, and both travel pumps one at a time, as follows:
1. Stop the engine.
2. Connect an accurate 0 to 1,000 psi (0 to 69 bar)
hydraulic pressure gauge to gauge coupler for desired
pump (Figure 2-16
).
3. Start and run the engine at low idle.
4. Note and record gauge reading. Gauge should read
325 to 375 psi (22,4 to 25,8 bar).
NOTE: Charge pressure can be monitored on diagnostic
screen for each function. Charge pressure shown
on the diagnostic screens can vary ±100 psi (6,9
bar) from that shown on the pressure gauges.
5. If proper pressure is not obtained, adjust charge
pressure relief valve for corresponding pump. See
instructions in pump manufacturer’s manual.
6. Stop engine and remove gauge from coupler
(Figure 2-16
). Install protective cap over coupler.

Manitowoc 2250 Specifications

General

Brand	Manitowoc
Model	2250
Category	Construction Equipment
Language	English