Emerson OCX 8800 instruction manual 10. O2 Cell, Heater Thermocouple, Exploded View

Instruction Manual

IM-106-880, Rev 1.0 January 2007

OCX 8800

Figure 7-10. O2 Cell, Heater,

and Thermocouple, Exploded

View

Do not remove the O2 cell unless you are certain it needs to be replaced. Removal may damage the cell and platinum pad. Remove the O2 cell for cell replacement only.

4

6

7

8

9

12

11

10

1.Screw

2.O2 Cell

3.Heater Tube

4.Contact/ Thermocouple Assembly

5.Gasket

6.Screw

7.Lockwasher

8.Return Wire

9.Heater Strut Assembly

10.Spring Clip

11.Spring

12.Strut Bracket

3

5

Test Gas

Passage

Holes

1 2 37390032

Disassemble O2 Cell and Heater Strut Assembly

Do not attempt to replace the O2 cell until all other possibilities for poor performance have been considered. If cell replacement is needed, order the O2 cell replacement kit (Refer to Section 9, Replacement Parts).

The O2 cell replacement kit contains an O2 cell and flange assembly, gaskets, socket head cap screws, and anti-seize compound. The items are carefully packaged to preserve precise surface finishes.

Do not remove items from the package until they are ready to be used.

1.Remove the four allen cap screws (1, Figure 7-10) from the O2 cell (2). Remove the O2 cell. The cell flange has a notch that may be used to gently pry the flange away from heater tube (3).

NOTE

The pad on the end of contact/thermocouple assembly (4) will sometimes fuse to the O2 cell (2).

2.If the O2 cell is fused to the contact pad, push the O2 cell back into the heater tube (against spring pressure) and quickly twist the O2 cell. The cell and contact pad should separate. If the contact pad stays fused to the cell, a new contact/thermocouple assembly (4) must be installed.

3.Remove and discard gasket (5). Clean the mating surface of heater tube (3). Remove burrs and raised surfaces with a block of wood and crocus cloth.

Use care when handling contact and thermocouple assembly. The ceramic rod in this assembly is fragile.

4.Remove screws (6), lockwashers (7), return wire (8), and heater strut assembly (9).

5.If replacing contact and thermocouple assembly (4), use a pencil to mark location of spring clip (10) before removing. Squeeze tabs on spring clip to remove. Retain spring clip and spring (11); replace if damaged.

6.While carefully handling new contact and thermocouple assembly (4) lay old assembly next to new one. Transfer match marks to new assembly.

7.Carefully guide new contact and thermocouple assembly (4) through strut bracket (12), spring (11), and spring clip (10) until spring clip reaches pencil mark.

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