17666 Mercury STOP, REED VALVE (5 H.P.)

Fuel leaked or spilled onto hot surfaces or electrical components can cause a fire. To help prevent possible injury, turn the start switch off when changing fuel filters or water separator elements. Clean up fuel spills immediately.
Keep all parts clean from contaminants.Contaminants may cause rapid wear and shortened component life.
Hot engine components can cause injury from burns. Before performing maintenance on the engine, allow the engine and the components to cool.
Turn the fuel supply to the OFF position.
Turn the battery disconnect switch to the OFF position.
Drain the coolant from the cooling system into a suitable container for storage or for disposal. Refer to Operation and Maintenance Manual, "Cooling System Coolant - Change" for the correct draining procedure.
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Remove allen head bolts (5) (not shown) from tube assembly clamps (6).
Disconnected fuel tube assembly (11) from ARD combustion head (9). Plug the tube assembly with new plugs. Cap all open connectors on the combustion head with new caps.
Disconnected tube assembly (2) and tube assembly (3) from ARD combustion head (9). Plug the tube assemblies with new plugs. Cap all open connectors on the combustion head with new caps.
Remove bolt (4) from the ground strap and disconnect ignition wire (1) from the spark plug.
Remove allen head screw (10) and remove clamp from the ARD combustion head (9). Remove heated nozzle connection (13) from the ARD combustion head.
Remove flame detection temperature sensor (12) from ARD combustion head (9). Refer to Disassembly and Assembly, "Flame Detection Temperature Sensor - Remove and Install" for the correct procedure.
Remove allen head bolts (7) and remove gasket (8) (not shown).
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Remove spark plug (15) from ARD combustion head (9). Refer to Disassembly and Assembly, "ARD Spark Plug - Remove and Install" for the correct procedure.
Loosen nuts (15) in a crisscross pattern. Remove nuts (15) from ARD combustion head (9).
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Remove ARD combustion head (9).
Remove gasket (18). Remove combustion tube assembly (17) and remove gasket (16).
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If necessary, follow Step 15.a through Step 15.b to remove fuel connection and the connections for the coolant from the ARD combustion head.
Remove fuel connection (24) from ARD combustion head (9).
Remove O-ring seal (23) from connection (24).
Remove coolant connection (19) and coolant connection (21) from ARD combustion head (9).
Remove O-ring seal (20) (not shown) from coolant connection (19).
Remove O-ring seal (22) (not shown) from coolant connection (21).
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If necessary, remove studs (26) from body (25) of the ARD.Installation Procedure
Table 1
Required Tools
Tool Part Number Part Description Qty
A 4C-5597 Anti-Seize Compound 1
B - Bostik Pure Nickel
Anti-Seize Compound 1
C 247-5377 Torque Wrench 1
Ensure that all components are clean and free from wear and damage. If necessary, replace any components that are worn or damaged.
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If necessary, install studs (26) to ARD body (25). Apply Tooling (A) onto the threads of studs (26). Install the studs to body (25) of the ARD.Tighten studs (26) to a torque of 17 N m (150 lb in).
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If necessary, follow Step 3.a through Step 3.d to install the fuel connection and the connections for the coolant to the ARD combustion head.
Ensure that the filter in fuel connection (24) is clean and free from damage. Ensure that the filter in the combustion head (9) is clean and free from damage.
Install a new O-ring seal (23) to fuel connection (24). Install the connection to ARD combustion head (9). Tigh