Maintenance

AIR COMPRESSORS - General Maintenance

All air compressors should be properly maintained to maximise both the reliability and the life time of the machine. Cleanliness internally will lead to good mechanical efficiency. Cleanliness externally will enable a more efficient dissipation of heat to the circulating air. Change the oil regularly.

DAILY
Oil - Check the crankcase oil and top up as required. Investigate high oil consumption. This could indicate possible faults with the pump. See fault finding guide.
Water - Water should be drained from the receiver by means of the drain valve underneath the receiver. Unscrew the knurled ring to release the water and re-tighten finger tight. A similar operation should be carried out on the after cooler and pressure regulator if fitted. Remember failure to drain the receiver will invalidate the warranty.
Leaks - Check for leaks from the compressor, fittings, delivery lines and couplings. Re-tighten or reseal as necessary. Even small leaks can cause wasted energy and a reduction in compressor life.
Air Filter - Check and clean as required by reverse blowing with compressed air. Badly contaminated air filters may need replacement cartridges.

WEEKLY (or after 50 hours)
Pressure Switch - Observe that the air compressor is cutting out at the correct maximum pressure, and back in at approximately 35psi, lower than the maximum Adjust as necessary.
Safety Valve - This is set to protect in case of pressure switch malfunction. With the receiver at maximum pressure the centre of the shaft can be lifted with ease to check this function always wear eye and ear protection.

MONTHLY (or after 200 hours)
Belt - With the mains isolated. Check motor pulley and pump flywheel should be in line and the movement on the vee belt at its mid point should not exceed 12mm. Check the tightness of the motor and pump securing bolts. Check the belt for wear. Also check that the fl ywheel and motor pulley are both secure on their respective shafts and that the securing bolts are tight.
Non Return Valve & Inserts - Non return valve (and balancer valve on tandem units) inserts and springs should be removed and examined. Oil, coke and scale deposits should be removed and any damaged inserts or springs replaced. The non return valve can be checked by stopping the machine at the black pressure switch (depress button). If the air continues to escape after the initial hiss then the inserts require attention or replacement. The air must be drained from the receiver before inspection/maintenance is carried out. A badly contaminated or worn non return valve must be replaced.

THREE MONTHLY
Inspect Air Receiver - Specific inspection instruction may be stated on the receiver test certificate, these should be followed in addition to any national legislation requirements regarding inspection and re-inspection relevant to air receivers. The air receivers on SIP compressors is manufactured according to the EEC Directive 87/404. This directive requires the receiver to be inspected, for external/internal corrosion or damage, quarterly, by the user and records kept of the inspection carried out. In addition, where applicable, your insurance company may wish to inspect the receiver annually.

FOUR MONTHLY (or after 500 Hours)
Oil - Drain oil and replenish to the correct level.
Valves - Pump efficiency largely depends upon the condition of the valve and valve seats. The cylinder head should be removed and the valves removed. Dirt / carbon / varnish should be brushed and washed away and the parts checked and dried before replacement. Chipped valve plates should be replace along with broken springs. Gasket sets can be supplied by local distributors. Where valves cannot be removed (riveted type), carefully clean all accessible carbon, particularly on the sealing faces of the valves. On replacing the cylinder head ‘gently’ tighten all bolts then secure in a diagonal pattern to ensure a uniform seal. Tighten to specified torque settings and follow the instructions under ‘Daily’ maintenance for cylinder head bolts, after each cylinder head removal/replacement.