The maintenance procedures for lubricating and cooling systems in air compressors are similar to the procedures used for lubricating and cooling systems in internal combustion engines. For air-cooled compressors, steps must be taken to keep the cooling fins clean. Oil and dust act as insulators and, if allowed to collect on the fins, will prevent heat transfer.

In general, the lubricating system of a compressor will give you little trouble if the following steps are taken:

1. Keep the reservoir oil at the prescribed level in order to maintain proper oil temperature.

2. Change crankcase oil periodically, flush the crankcase, and clean the oil filter.

3. Maintain proper lube oil pressure by keep-ing the oil pump in good working condition and by adjusting the bypass relief valve.

4. Keep the oil cooler free from leaks to pre-vent oil contamination and emulsification.

5. Inspect cylinder lubricators.

a. When Navy Symbol 9000 series oil is used for compressor cylinder lubrication, the sight flow indicators should be filled with glycerine alone.

b. When Navy Symbol 2000 series oil is

used for cylinder lubrication, the sight flow indicators should be filled with a mixture of 50% distilled water and 50% glycerine.

6. Keep the lubricator in proper adjustment for the specified quantity of oil feed.

The general requirements for care and maintenance of compressor cooling systems are as follows:

1. Intercoolers and aftercoolers should be in-spected periodically.

2. Collections of gummy oils or tarry substances on the sides of cooler tubes should be removed by washing the tube nests with a cutting solution. Be sure that the nests are completely dry before reassembly.

3. Any leaks in tube nests must be repaired; otherwise, water will leak into the compressor while it is secured, and air will leak into the water side during operation.

If during operation, a water relief valve on the coolers blows while the cooling water pressure is normal, it is evident that a tube in the cooler is ruptured. The compressor should be secured immediately and the tube plugged, if possible.

4. Cylinder water jackets should be inspected and cleaned periodically with a cleaning nozzle.

5. When the cooling water system of the compressor is being refilled, the water inlet valve should be opened slightly to allow the water to rise slowly in the cooler shell and water jackets.

Also, the vent valves which are fitted to the water spaces should be opened to permit entrapped air to escape, and thus prevent the formation of air pockets in the system.