The above mentioned cylinder is a water to oil heat exchanger and also serves as an oil filter housing. You will notice a large diameter hose running from the radiator to the heat exchanger and another one from the heat exchanger to the water pump.
Several problems present themselves to the owner.
Just like a radiator, the heat exchanger has a large number of thin tubes through which the engine coolant must flow and like a radiator, these tubes can become clogged with calcium deposits, lumps of old gasket sealer, etc. This condition will of course cause the engine to overheat due to coolant flow restriction. If your Maserati is running hot, having the radiator and heat exchanger -flow checked by a radiator expert may give you the reason. Never put anything but distilled water and quality antifreeze in your Maserati's cooling system by the way. The other main problems that can be encountered lie with the oil filtering part of the system.