This is an Automobile Air Conditioning freon pump.

As you can see this one has been over worked to the point of explosion. During the course of deterioration of this unit, the operator of the vehicle would have noticed signs that something was wrong. They would have been hearing a knocking sound and the engine idle would have been very poor. At idle the engine would have been shaking the car. 

It this problem would have been checked by a professional when the operator first noticed a change in the sound and operation of the engine, this problem could have been repaired long before this state of repair occurred. Because the problem wasn't addressed in the early stages the damage is clearly more complex. The destruction of the compressor has contaminated the entire air conditioning system. What could have been $700.00 repair turned into a $2,000 repair.