Problem Solving; Problem Solving Chart; Alternator Precautions - Atlas Copco XAS 185 CD7 T4F HOP Instruction Manual

Problem solving

PROBLEM SOLVING CHART

Use the chart on the following pages to help solve
mechanical problems.
It is assumed that the engine is in good condition, that
there is adequate fuel flow to the filter and injection
equipment, and compressor/engine maintained with the
recommended oil.
An electrical fault must be traced by an
electrician.
Problem: Compressor capacity or pressure below normal.
Possible faults
Air consumption exceeds capacity of compressor.
Choked air filter elements (AF).
Regulating valve (RV) defective.
Blow down valve stuck in open position.
Loading valve (LV) leaking past O-ring.
Oil separator element clogged.
Air intake throttle valve remains partially closed.
Safety valve (SV) leaking.
Blow-off valve leaking.
Problem: Pressure in air receiver rises above maximum and causes safety valve to blow.
Possible faults
Regulating valve (RV) opens too late or its ball valve spring is broken.
Air leaks in regulating system.
Air intake throttle valve does not close for some reason.
Minimum pressure valve malfunctioning.
Blow-off valve malfunctioning.
Make sure that the wires are not damaged and that they are
clamped tight to their terminals.

ALTERNATOR PRECAUTIONS

1. Never reverse the polarity of the battery or the
alternator.
2. Never break any alternator or battery connections
while the engine is running.
Corrective actions
Check equipment connected.
Remove and inspect elements. Clean or replace, if necessary.
Have regulating valve removed and inspected by an Atlas copco Service representative.
Check and correct as necessary.
With compressor running at maximum load speed, disconnect hose leading to unloader. If air leaks from the hose,
remove and inspect loading valve. Replace damaged or worn O-rings.
Have element removed and inspected by an Atlas copco Service representative.
Check unloader and identify reason for open valve; if possible: solve; else: contact Atlas copco.
Remove and inspect. Replace if not airtight after reinstallation.
Remove and inspect. Replace if necessary.
Corrective actions
Have regulating valve removed and inspected by an Atlas copco Service representative.
Check hoses and their fittings. Stop leaks; replace leaking hoses.
Check unloader and identify reason for open valve; if possible: solve; else: contact Atlas copco.
Remove and inspect valve.
Remove and inspect valve.
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3. When recharging the battery, disconnect it from the
alternator. Before using booster cables to start the
engine, be sure of the polarity and connect the batter-
ies positive to positive, negative to negative.
4. Never operate the engine without the main or voltage
sensing cables connected in the circuit.