DISC 8Q5362 - Caterpillar

Hot engine components can cause injury from burns. Before performing maintenance on the engine, allow the engine and the components to cool.
Turn the battery disconnect switch to the OFF position.
Turn the fuel supply to the OFF position.
Illustration 1 g03645015
Open grill assembly (1).
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Remove shield (2).
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Loosen clamp (3). Cut cable strap (4).
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Disconnect hose assemblies (5).
Disconnect temperature sensor (6).
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Remove bolt (8). Disconnect wire assemblies (7).
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Disconnect tube assembly (9).
Disconnect hose assembly (10).
Remove screw (12) and clamp (11) in order to disconnect wire assembly (13).
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Remove O-ring seals (14) and (15) from wire assembly (13).
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Remove nuts (16). Remove combustion head (17) and tube assembly (18) as one.
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Remove combustion tube (20) and gaskets (19). Gaskets (19) are not reusable. Discard gaskets (19).
Do not remove studs (21).
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Remove tube assembly (18) and the gasket from combustion head (17).
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Remove fittings (22) and fittings (24). Remove spark plug (23). Installation Procedure
Install combustion head (17) in the reverse order of removal.
Tighten spark plug (23) to a torque of 58 4 N m (43 3 lb ft).
Tighten fittings (22) to a torque of 60 6 N m (44 4 lb ft).
Tighten fittings (24) to a torque of 30 2 N m (22 1 lb ft). The final torque must occur within 16°-43° of rotation from a pre-torque level of 10 N m (89 lb in).
Install new gaskets (19).
Apply Tooling (A) to the threads of studs (21).
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Nut tightening sequence.
Tighten nuts (16) in a crisscross pattern, as shown in Illustration 12, to a torque of 23 3 N m (204 27 lb in). Tighten nuts (16) again in a crisscross pattern, as shown in Illustration 12 to a torque of 28 3 N m (21 2 lb ft). Tighten nuts (16) again in a crisscross pattern, as shown in Illustration 12 to a torque of 28 3 N m (21 2 lb ft).
Be sure that wire assembly (13) is free of oil and lubricants during the assembly process.
Apply Tooling (B) to the threads of temperature sensor (6). Tighten temperature sensor (6) to a torque of 45 5 N m (33 4 lb ft).
Refer to Troubleshooting Manual, "ARD Ignition - Test" and Special Instructions, REHS4824 , "Replacement of the ARD Combustion Head on Caterpillar Products with Clean Emissions Modules".