Heat exchanger including a bank of finned tubes and a shell surrounding said bank

A heat exchanger, in particular for motor vehicles, including at least one water tank disposed at one end of a bank (6) of tubes (8) with fins (7) through which a first fluid flows, and a shell (2), such as a casing (9), defined by walls (12, 13, 14, 15), surrounding said bank and through which a second fluid flows, in which heat exchanger two sides of the bank are adjacent to the walls (12, 13, 14, 15) of the casing (9), which are braced against one another by assembly means that position the bank (6) and are supported thereby, characterized in that the assembly means comprise sliding mortise and tenon mutual engagement means (21, 23, 25, 26, 34) carried respectively by the bank (6) and at least one of the walls (12, 13, 14, 15) of the casing (9), forming means of bracing and retaining said walls, and wherein said tenon (23) is formed on an inside face (22) of at least one wall (12, 13) of the casing (9), the mortise (21) being formed on at least one front face of the bank (7) of tubes (8) having fins (7).