Abstract: An expansion tank is disclosed in which a non-return valve is fitted in an outlet port of the expansion tank to limit backflow of coolant into the expansion tank in the event that the pressure in the expansion tank falls below the pressure in a return conduit thereby preventing the expansion tank from filling with coolant. The non-return valve and the expansion tank are formed as a single component and the non-return valve is located in an outlet port of the expansion tank.

Abstract: An expansion tank for an engine cooling system comprises a housing forming a main chamber and a swirl chamber, the swirl chamber being defined by a cylindrical wall. An inlet connection discharges through an inlet orifice towards a collector duct having an entrance. From the inlet orifice the coolant is directed as a stream or jet along the adjacent surface of the cylindrical wall towards the entrance of the collector duct, guided by circumferential ribs. The kinetic energy of the stream is converted into pressure energy so that the pressure delivered from the outlet connection is slightly above the pressure at the top of the swirl chamber, above the level of liquid. This swirl chamber pressure is set by the relief pressure allowed by a filler cap, the gain in pressure helping to avoid cavitation in a coolant circulation pump.

Abstract: A temperature responsive control valve is disclosed. The valve may have a housing having a hot inlet, a cold inlet and an outlet. A first valve member, and a second valve member, may be configured to move within the housing to selectively prevent and permit flow from the hot inlet and the cold inlet to the outlet when a sensed temperature is within predetermined ranges. A temperature responsive actuator may be disposed to move the first and second valve members within the housing in accordance with the sensed temperature. A first bias may be configured to bias the first valve member toward preventing flow from the hot inlet to the outlet, and a second bias may be configured to bias the second valve member toward preventing flow from the cold inlet to the outlet.

Abstract: A expansion tank for an engine cooling system comprises a housing forming a main chamber and a swirl chamber, the swirl chamber being defined by a cylindrical wall. An inlet connection discharges through an inlet orifice towards a collector duct having an entrance. From the inlet orifice the coolant is directed as a stream or jet along the adjacent surface of the cylindrical wall towards the entrance of the collector duct, guided by circumferential ribs. The kinetic energy of the stream is converted into pressure energy so that the pressure delivered from the outlet connection is slightly above the pressure at the top of the swirl chamber, above the level of liquid. This swirl chamber pressure is set by the relief pressure allowed by a filler cap, the gain in pressure helping to avoid cavitation in a coolant circulation pump.

Abstract: A temperature responsive control valve is disclosed. The valve may have a housing having a hot inlet, a cold inlet and an outlet. A first valve member, and a second valve member, may be configured to move within the housing to selectively prevent and permit flow from the hot inlet and the cold inlet to the outlet when a sensed temperature is within predetermined ranges. A temperature responsive actuator may be disposed to move the first and second valve members within the housing in accordance with the sensed temperature. A first bias may be configured to bias the first valve member toward preventing flow from the hot inlet to the outlet, and a second bias may be configured to bias the second valve member toward preventing flow from the cold inlet to the outlet.

Abstract: A heat exchanger 11 for use as a cross flow radiator for an engine cooling system has a heat exchanger matrix 12, header tanks 13, 14 and a side plate 16 arranged at the upper of a pair of opposite side edges 16, 17 of the matrix 12. The matrix 12 has tubes 18 which extend between tanks 13, 14 and cooling fins 19. A restrictor plate 21 arranged on side plate 16 restricts air flow past fin 19A. Restrictor plate 21 may have cut out gaps or castellations 22. This reduces heat transfer through the fins above the uppermost tube 18A allowing for a more even temperature distribution, which reduces stress from thermal expansion.

Abstract: A heater diverter valve (20) is provided in an engine cooling system having a radiator and a circulating pump, The valve has a first inlet (31) connected to a heater so that coolant flowing through the engine and then through the heater is returned to the pump return line through the valve via the first inlet and an outlet (33). A second inlet (32) is connected to engine and transmission oil coolers so that coolant which flows from the engine supply line through the coolers is returned to the pump return line via the second inlet and the outlet. The valve includes a shuttle (24) which at lower coolant temperatures closes off the second inlet (32) to prevent coolant flow. The second inlet (32) is opened at higher temperatures when a wax type thermal actuator pushes the shuttle towards the first inlet (31).

Abstract: A vehicle (10) is disclosed which includes a thermostat (22) in a bottom hose (24) of a radiator (16). An onboard diagnostic arrangement is provided to monitor the efficiency of the thermostat (22). Temperature sensors (S1, S2) are provided to monitor the temperature of the coolant across the radiator (16) so that a controller (40) can derive from those measurements the temperature differential across the thermostat (22). If the temperature Teng of the coolant at the thermostat inlet is below the thermostat opening temperature Topen and the differential temperature between the thermostat inlet temperature Teng and the thermostat outlet temperature Trad is below a fault threshold Dtstat, the thermostat (22) is evaluated as being stuck open or leaking, which results in a fault being recorded and a malfunction indicator lamp (MIL) being illuminated.

Abstract: A separator (8) for separating liquid from gas is disclosed in which two or part cylindrical chambers (12, 12', 14, 14', 16) are arranged to produce contra-rotating vortices therein when a liquid and gas mixture is passed therethrough. The change in direction of the flow when passing from one chamber to the next and the centifugal effect of the vortex flow separates the denser fluid from the less dense gas.

Abstract: To ensure an adequate supply of hot engine coolant to a heater circuit at low engine speeds, a combined thermostat and bypass valve 10 is arranged to restrict bypass flow by means of a spring-loaded bypass valve 38 operating at a bypass delivery port 16. At low engine speeds the bypass flow pressure is insufficient to lift the bypass valve 38 from its seating and the flow through a heat exchanger "H" in the heater circuit is thereby enhanced.

Abstract: A cooling circuit for an internal combustion engine is disclosed in which the bypass and thermostat assembly includes means to prevent relatively cold coolant entering the thermostat assembly from a bottom hose to impinge upon a temperature sensitive valve actuating means. The bypass and thermostat assembly is therefore unaffected by relatively colder coolant entering the assembly as the temperature sensitive part of the thermostat remains immersed in relatively warm coolant entering the assembly through a bypass hose even when the bypass is closed.

Abstract: An internal combustion engine comprises an iron block 2 and an aluminium head 3 held together by bolts 6. The bolts 6 extend through oil drainage passages 8 in the head and through bores 9 in the block and engage with the block at a point substantially spaced from the head/block interface. The increased length of the bolts 6 allows them to stretch to accommodate the relatively large expansion of the head as the engine warms up. Good thermal contact is provided between the bolts and the water jacket of the engine so that the bolts warm up quickly.

Abstract: An internal combustion engine has a cylinder head assembly with a camshaft 28 mounted therein and breather passages 70 through it. A guard member 38 is mounted on the head casting 12 and includes guards 40 over the cams 42 side walls 39 and a bearing ladder for the camshaft. A gasket 46 between the guard member 38 and a cover 44 forms, with the guard member 38, a separation region 50 having an inlet 72 fed by the breather passages and outlets 51 in the form of holes through the gasket 46. The gas can flow from the breather passages to the outlets 51 is slow and substantially horizontal so oil can separate out of the gas. The guards 40 prevent oil from the cams 42 from mixing with the breather gases.

Abstract: An internal combustion engine 20 comprises a cylinder block 22, a cylinder head 24, and a plurality of fasteners 47 holding the head onto the block. The block comprises a single structure having walls 34 defining four cylinder bores 36 arranged in a line for receiving pistons, longitudinal support sections 60, 61 extending along the block one on either side of the line of bores and transverse support sections 74 joined to the longitudinal support sections and extending substantially tangentially to the bores. The fasteners 47 are arranged to engage with the block 22 such that a substantial part of the load exerted on the top of the walls 36 of the bores is transmitted to the fasteners via the support sections. This prevents forces from being transmitted radially into the cylinder walls 36 and thereby reduces bore distortion.