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In assembly of engine block mold package, a water jacket slab core is assembled on a barrel crankcase core having a plurality of barrels on which cylinder bore liners are positioned. Some of the barrels include a core print on a distal end thereof. The water jacket slab core includes a plurality of

In assembly of engine block mold package, a water jacket slab core is assembled on a barrel crankcase core having a plurality of barrels on which cylinder bore liners are positioned. Some of the barrels include a core print on a distal end thereof. The water jacket slab core includes a plurality of core prints each in mating relation with a respective barrel core print and a plurality of bore liner positioning surfaces that each engage a respective distal end of a respective cylinder bore liner when the water jacket slab core is assembled on the barrels.

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In assembly of engine block mold package, a water jacket slab core is assembled on a barrel crankcase core having a plurality of barrels on which cylinder bore liners are positioned. Some of the barrels include a core print on a distal end thereof. The water jacket slab core includes a plurality of

In assembly of engine block mold package, a water jacket slab core is assembled on a barrel crankcase core having a plurality of barrels on which cylinder bore liners are positioned. Some of the barrels include a core print on a distal end thereof. The water jacket slab core includes a plurality of core prints each in mating relation with a respective barrel core print and a plurality of bore liner positioning surfaces that each engage a respective distal end of a respective cylinder bore liner when the water jacket slab core is assembled on the barrels. er to open the main valve or to a close chamber to close the main valve and the main valve connected to a source of pressurized supply fluid to selectively direct such supply fluid to a downstream apparatus, the spool valve and the main valve both vented to atmosphere, the spool valve comprising: an elongate movable spool positioned in an axial bore, the spool moving from an extended position which opens the spool valve to a retracted position which closes the spool valve, to selectively direct the flow of the pilot fluid through the spool valve to the main valve, one end of the movable spool selectively exposed to pressurized supply fluid; the elongate movable spool having at least three lands of different diameters to control movement of the spool from the extended position to the retracted position; a spring chamber in selective fluid communication with pilot fluid; a spring captured in the spring chamber urging the movable spool into the extended position; a pilot fluid passageway to allow pilot fluid to flow from the pilot valve to the spool valve, an open passageway to allow pilot fluid to selectively flow to the spring chamber and selectively flow from the spool valve to the open chamber, a close passageway to allow pilot fluid to selectively flow from the spool valve to the close chamber, and a vent passageway to atmosphere; when the spool valve is in the open position and the main valve is in the closed position, the pilot valve is actuated allowing pilot fluid to flow through the pilot fluid passageway, the spool valve, the open passageway to the open chamber causing the main valve to open, and the open passageway also allows pilot-fluid to flow into the spring chamber to keep the movable spool in the extended position; after the pilot valve is closed the pilot fluid in the spool valve is vented to atmosphere and the movable spool shifts from the extended position to the retracted position in response to supply pressure while the main valve remains open; actuation of the pilot valve a second time causes pilot fluid to flow through the pilot fluid passageway and the spool valve through the close passageway to the close chamber causing the main valve to close; and when the pilot valve is closed and pilot fluid in the spool valve is vented to atmosphere, the movable spool shifts from the retracted closed position to the extended open position in response to urging from the spring, while the main valve remains closed. 2. The apparatus of claim 1 further including another land wherein the diameter of the first land and the second land are the same and the diameter of the second land being greater than the diameter of the third land and the diameter of the third land being greater than the diameter of the fourth land, when the spool valve is in the open position and the main valve is in the closed position, and the pilot valve is actuated, pilot fluid acts on the first land so the spool stays in the extended position while the third land is exposed to pressurized supply fluid, after the pilot valve is closed and the pilot fluid is vented to atmosphere, the pressurized supply fluid acts on the third land to shift the spool to the retracted position; actuation of the pilot valve a second time causes pilot fluid to act on the differential area between the second land and the third land to hold the spool in the retracted position while the pressurized supply fluid is vented to atmosphere; and when the pilot valve is closed and the pilot fluid is vented to atmosphere, the movable spool shifts to the extended position in response to urging from the spring. 3. A spool valve connected to a single pilot valve and a main valve to open and close the main valve in response to fluid signals from the pilot valve, the pilot valve connected to a source of pilot fluid so the spool valve can selectively direct such pilot fluid to an open chamber to open the main valve or to a close chamber to close the main valve and th