Piston-type compressor, two-cylinder, single-stage compression, capacity 220 l/min, crankshaft speed 2000 rpm and back pressure 700 kPa; mounted on the front end of the flywheel housing.

Compressor gear drive from distribution gears; head cooling from the cooling system, oil is supplied from the lubrication system.

Kamaz car compressor

Air through the air cleaner and the engine intake pipe enters the compressor cylinders through the reed inlet valves.

Kamaz compressor

The air compressed by the pistons is displaced into the receivers through the reed pressure valves located in the cylinder head.

After reaching a pressure of 700 ... 750 kPa, the pressure regulator communicates the pressure line with the atmosphere, which stops the air supply to the pneumatic system.

For seasonal maintenance, the compressor head must be removed to clean the pistons, valves, and seats.

Compressor valves that fail to seal must be lapped or replaced.

In the pressure regulator, it is necessary to wash or replace the filter element, which is located under the bottom cover.

You need to be careful when screwing the cover, as the thread is tapered and distortions during its installation are unacceptable. They lead to thread breakage, which is then impossible to restore.

Before installation, it is recommended to lubricate the thread with graphite grease to prevent it from “seizing”.

As the compressor works, the cylinder-piston group wears out, the tightness of the valves is broken.

In case of these malfunctions, the filling time of the pneumatic system (until the control lamps go out) at a crankshaft speed of 2200 rpm exceeds the set value of 8 minutes or the compressor does not develop the set pressure at all (700 ... 750 kPa).

In addition, the wear of the cylinder-piston group leads to the suction of oil into the pneumatic system.

After filling the pneumatic system with air in the pressure regulator, the unloading valve opens and the oil that has entered the pneumatic system along with the air is thrown out and settles on the regulator and frame. This is an external sign of a compressor malfunction.

It should be noted that oil flow through the compressor may increase due to clogged air cleaner.

As the clogging increases, the vacuum at the inlet increases and the compressor, even with a working piston group, sucks in oil mist from the crankcase, and then ejects it into the pneumatic drive at the outlet.

Leakage of the compressor cylinder head gasket, internal cracks in the head or block lead to the fact that the liquid from the cooling system is sucked into the cylinders, and then, together with the air, goes to the pneumatic drive.

The coolant level in the expansion tank drops, and the liquid in it boils. This is because the piston on the compression stroke pushes air into the compressor cooling jacket, and then the air with liquid is discharged into the expansion tank.

There is another dangerous consequence of the considered malfunctions

The liquid that has entered the compressor cylinders, through the gaps between the cylinder, piston and rings, seeps into the compressor crankcase and flows from it into the engine oil crankcase. Therefore, when looking for a place where coolant enters the oil, it is necessary to keep in mind the compressor.

Brake malfunctions are most often caused by malfunctions of the pneumatic drive apparatus.