Stanley MB556, User Manual

MB556 

User

 Manual ◄ 15

This section describes how to find and resolve problems 

users may experience. If a situation occurs that is 

not covered, call your STANLEY Customer Service 

Representative for assistance.

PROBLEM

CAUSE

SOLUTION

Breaker will not fire.

Low hydraulic oil level.

Fill reservoir.

No flow to breaker.

Have hydraulic circuit tested by 

authorized dealer/distributor per 

approved procedure.

Main relief set low.

Internal damage.

Have unit serviced by an authorized 

dealer/distributor.

Damaged quick couplers.

Replace.

Breaker runs slowly.

Low hydraulic flow

Have hydraulic circuit tested by an 

authorized dealer/distributor per 

approved procedure.

Excessive heat build up.

Excessive nitrogen pressure.

Have unit serviced by an authorized 

dealer/distributor.

Internal leakage.

Breaker runs erratically.

Low or excessive back-pressure.

Have carrier serviced by an authorized 

dealer/distributor.

Damaged switch or connection.
Relief set too low.
Internal damage.
Tool binding.

Add grease to tool shank. Do not pry 

while operating.

Breaker runs but at reduced 

power.

Low accumulator charge.

Have unit serviced by an authorized 

dealer/distributor.

Excessive back-pressure.
Relief set too low.

Breaker leaks oil around tool bit 

and tool bushing.

Lower seals failed.

Have unit serviced by an authorized 

dealer/distributor.

Hydraulic system overheats.

Main relief set low.

Have unit serviced by an authorized 

dealer/distributor.

Insufficient cooling capability in 

hydraulic circuit.
Line/hose size too small.
Excessive back-pressure.

If symptoms of poor performance develop, the following 

chart can be used as a guide to correct the problem.
When diagnosing faults in operation of the tool, always 

check that the hydraulic power source is supplying the 

correct hydraulic flow and pressure to the tool as listed in 

the table below. Use a flowmeter known to be accurate. 

Check the flow with the hydraulic oil temperature at least 

80 °F/27 °C.

Inspecting the tool or installing parts with the 

hydraulic hoses connected can result in severe 

personal injury or equipment damage. To prevent 

accidental startup, disconnect the hydraulic power 

before beginning any inspection or installation task.

TROUBLESHOOTING