Manitowoc 2250 Service And Maintenance Manual

Reference Only
Manitowoc Published 11-06-15, Control # 040-13 10-57
2250 SERVICE/MAINTENANCE MANUAL TROUBLESHOOTING
10
Test 22 — Adjusting the Counterbalance Valves
Each jacking cylinder has a single counterbalance valve at
the piston end of the cylinder. The retract adjusting screw at
the valve provides adjustment for each jacking cylinder load
support. The extend adjusting screw allows cylinders to be
adjusted for uniform operation on level ground.
Counterbalance valves are pre-adjusted at the factory, but
are not calibrated. Adjust counterbalance valves with a
closed end wrench and hex wrench. To avoid over-adjusting
the cylinders, use a hex wrench as a guide and never turn a
counterbalance valve more than 1/2 turn in either direction.
To adjust a counterbalance valve:
• Loosen the adjusting lock nut.
• Rotate the counterbalance adjusting screw 1/2 turn
clockwise (in) to lower the holding pressure.
• Rotate the counterbalance adjusting screw 1/2 turn
counter-clockwise (out) to raise the holding pressure.
• While holding the counterbalance adjusting screw with
hex wrench, tighten the lock nut.
• Recheck the cylinder(s) for correct load support and
uniform operation.
Item Description Item Description
1 Gantry cylinder (right side) 6 Boom butt-handling counterbalance (rod end)
2 Gantry lifting counterbalance (rod end – outboard) 7 Jacking cylinder
3 Gantry lifting counterbalance (piston end – inboard) 8 Jacking cylinder extend adjusting screw
4 Boom butt-handling cylinder 9 Jacking cylinder retract adjusting screw
5 Boom butt-handling counterbalance (piston end)
Right side cylinder shown, for left side
cylinder (item 2) is inboard and (item 3) is
outboard
3
P893
1
2
P1527
6
P901
4
5
8
7
P904
P905
9
Example
WARNING
Possible Component Damage!
Special instructions/warnings apply when adjusting gantry
cylinders and boom butt cylinder counterbalance valves
as specified in Shop Procedure topic, Section 2 of this
manual. This procedure MUST be followed to ensure
cylinder adjustments are performed safely and correctly
with rod end or piston end adjusting screws. Gantry
cylinders will not extend evenly without counterweights
attached to crane. Gantry cylinder adjustments must be
performed with counterweights installed.

Manitowoc 2250 Specifications

General

Brand	Manitowoc
Model	2250
Category	Construction Equipment
Language	English