309-03114-0 Tohatsu BOLT, CARBURETORY BODY BAND

Illustration 1 g03096196
Cooling system schematic
(1) Turbocharger inlet coolant line for bearings
(2) Turbocharger
(3) Coolant outlet line from turbocharger
(4) Outlets from temperature regulator housing to radiator top
(5) Temperature regulator housing (both sides)
(6) Radiator
(7) Outlet bonnet of engine oil cooler, transmission oil cooler, and hydraulic oil cooler
(8) Transmission oil cooler
(9) Hydraulic oil cooler
(10) Engine oil cooler
(11) Inlet bonnet of engine oil cooler
(12) Inlet bonnet of transmission oil cooler
(13) Water pump
(14) Water pump inlet, from radiator bottom
(15) Radiator bypass lines When the engine is cold, the water temperature regulator is closed, and the coolant is stopped from going to the radiator. Instead the coolant goes from the temperature regulator housing (5) back to the water pump (13) through radiator bypass lines (15).
Illustration 2 g03064797
(16) Tank
(17) Power train oil cooler
(18) Right thermostat
(19) Left thermostat
(20) Vent tube
(21) Vent valve
(22) Engine block
(C1) Location for a tap
(C2) Location for a tap
(C3) Location for a tap A small amount of coolant also moves constantly through line (1) that connects from the water pump outlet to the center section of turbocharger (2). The coolant flows through passages around the turbocharger bearings and then out the front of the center section. The coolant then flows through line (3) up to the tank (16).When filling the cooling system the vent valve (21) on the vent tube (20) must be open to permit proper venting.When operating under normal conditions the vent valve (21) should be closed.Coolant Conditioner (If Equipped)
Some conditions of operation can cause pitting. Pitting can cause corrosion or cavitation erosion on outer surfaces of the cylinder liners and inner surfaces of the cylinder block next to the liners. The addition of a corrosion inhibitor, a chemical that gives a reduction of pitting, can keep this type of damage to a minimum.The "spin-on" coolant conditioner element is similar to the fuel filter and oil filter elements. The coolant conditioner element fastens to a base .and is part of the regulator housing on the left front of the engine. Coolant flows from the water pump through the cylinder head to the base. From the base the coolant flows through the element and back through the bypass line to the water pump inlet. There is a constant flow of coolant through the element when valve is in the "ON" position.The element has a specific amount of inhibitor for acceptable cooling system protection. As coolant flows through the element, the corrosion inhibitor, which is a dry material, dissolves into the solution and mixes to the correct concentration. Two types of elements are used for the cooling system, the "Precharge" and the "Maintenance" element. Each type of element has a specific application and must be used correctly to get the necessary concentration for cooling system protection. The element is also a filter that removes unwanted material from the coolant.The "Precharge" element has more than the normal amount of inhibitor. The "Precharge" element is used when a system is first filled with new coolant, unless Dowtherm 209 Antifreeze is used. This element has to add enough inhibitor to bring the complete cooling system up to the correct concentration.The "Maintenance" elements have a normal amount of inhibitor and are installed at the first change interval. The "Maintenance" elements provide enough inhibitor to keep the corrosion protection at an acceptable level. From the first change on, only "Maintenance" elements are installed at specified intervals to give protection to the cooling system.
Do not use Dowtherm 209 Full-Fill in a cooling system that has a coolant conditioner. These two systems are not compatible (corrosion inhibitor is reduced) when used together.