18212-ZY6-000 Honda GASKET, IDLE EX. PORT (Honda Code 7634181).

Adaptability
* 8R0448 Governor Control Group* 8R1902 Governor Control Group* 8R1234 Governor Control Arrangement* 8R1235 Governor Control ArrangementIntroduction
This special instruction contains the necessary information to install, adjust and troubleshoot the new governor control groups (Automatic Engine Speed Control) for the machines listed above. The groups affected are the 8R0448 and 8R1902 Governor Control Groups.Also included are the 8R1234 and 8R1235 Governor Control Arrangements for machines equipped with clamshell, front shovel bottom dump bucket, hammer or grapple attachments. Machines equipped with a two speed control pedal for boom raise and stick out speed are not covered in this instruction. Component relocation is necessary for these machines, requiring a different lines group.See the following chart for the applicable governor control groups. Reference: Service Manual, Parts Book, Operation & Maintenance ManualSystem Function
With the mode switch in the Mode 1 position (left) or Mode 2 position (right), the Automatic Engine Speed Control reduces engine speed to a pre-set speed setting during periods when there is no operator demand for engine power. The operator's demand for engine power is determined by sensing the pilot pressure from the four joystick functions (boom, bucket, stick and swing) and electrical signals from the auxiliary and travel functions. This engine speed reduction during "non-use" periods results in fuel savings.When the mode switch is set in Mode 1 and the governor control lever is set in the high idle position, the engine speed is reduced to the pre-set low speed setting when the highest pilot pressure is below 140 kPa (20 psi) for more than three seconds. Engine speed returns to high idle when the highest pilot pressure is above 140 kPa (20 psi) or the travel or auxiliary circuits are activated.If the mode switch is set in Mode 2 and the governor control lever is set in the high idle position, engine speed goes to a pre-set intermediate speed whenever the highest pilot pressure is above 140 kPa (20 psi). Engine speed will go to the high idle setting if travel or auxiliary circuits are activated. Engine speed is reduced to the low speed setting when the highest pilot pressure activated is below 140 kPa (20 psi) for more than three seconds.The Automatic Engine Speed Control linkage in the operator's station is preset to determine the low and intermediate speed settings. The governor lever does not move when the engine speed changes.Component Descriptions
The following chart lists the major components of the automatic engine speed control, the locations of the components and a brief description of the functions. Necessary Parts
The following charts list the necessary parts for each governor control group and for machines which are not equipped with travel alarm. Order only the groups which are applicable to your machine.8R0448 Governor Control Group
8R1902 Governor Control Group
8R1234 Governor Control Arrangement
8R1235 Governor Control Arrangement
Additional Parts for Machines NOT Equipped With Travel Alarm
Installation Procedure
1. Disconnect the hydraulic pilot lines, governor control linkage and electrical connections to the cab and operator's platform as necessary. Remove the cab. Remove the platform and position it on its side for access to the top and bottom sides.
Top View of Platform2. Disconnect supply tube (1) and remove 3R9704 Elbow (2) from the selector valve. Install 7D0978 Tee (3) in the selector valve and connect tube (1) to the tee. Reinstall elbow (2) into the bottom of the tee and connect a 306936 Reducer with a 8M0744 Nut to elbow (2).3. Remove and discard eight tube assemblies which connect the bulkhead to the pilot valves. Install eight 619258 Tees to the bulkhead unions then install 9C7915 Tube Assembly (4), 9C7916 Tube Assembly (5), 9C7914 Tube Assembly (6), 9C7913 Tube Assembly (7), 9C7912 Tube Assembly (8), 9C7911 Tube Assembly (9), 9C7910 Tube Assembly (10) and 9C7909 Tube Assembly (11).4. Disconnect drain tube (12) from the manifold drain elbow. Remove and discard the elbow, then replace it with 530700 Tee (13) and reconnect drain tube (12).5. If the machine is NOT equipped with a travel alarm, remove the 2V8909 Tube Assembly from between the directional control valve and the bulkhead. Replace the tube assembly with 3V8869 Tube Assembly (14), 7K4128 Tee (15) and 3V8868 Tube Assembly (16). Then install 8S7169 Coupling (17) and 9D7032 Switch (18) into tee (15).
Bottom View of Platform6. Fasten 7X1902 Control Group (19) to the bottom of the platform with two 8C0617 Bolts and 1A8912 Washers.
Do not over tighten the differential pressure switch during installation. The switch will malfunction if a higher than recommended torque is applied.
Complete steps 7 through 12 to build-up the pressure switch sub-assembly before installing to the bottom of the operator's platform.7. Connect 7X6081 Differential Pressure Switch Assembly (20) to 9C3397 Block (21) using a 1J9671 Seal. Tighten to 20 5 N m (15 4 lb ft).8. Install 3J7352 Connector (22) using a 3J7354 Seal. Tighten to 16 4 N m (12 3 lb ft).9. Install 307942 Elbow (23) using a 3J1907 Seal.10. Install 8J9990 Orifice Plug (24) using a 3J1907 Seal. Install a 6M6853 Tee (25) into plug (24) using a 3J1907 Seal.11. Install a 308142 Reducer and 3R4437 Nut (26) to the center port of Tee (25). Attach 9C3652 Tube Assembly (27) to the reducer and to connector (22).12. Fasten the sub-assembly to the bottom of the platform with two 8C6876 Bolts and 5P4116 Washers through block assembly (21).
Bottom View of Platform13. Install eight 2P1278 Unions (28) in the inlet ports of 9T1725 Check Valve Groups (29) using 3J1907 Seals. Fasten the check valves to 9C7908 Bracket (30) with 2P1279 Locknuts (31).14. Install 307942 Elbow (32) in the outlet port of check valve (29) using a 3J1907 Seal. Install two 2R6806 Connectors in outlet ports (A) using 3J1907 Seals then fasten 9C3310 Tube Assembly (33) to the connectors.15. Install nine 9S4191 Plugs in the unused check valve ports using 3J1907 Seals.16. Remove and discard the two bottom tube clamps which secure the supply tubes for the speed and directional control valve to two support channels. Replace the bottom clamps with 9C7908 Bracket (30) and two