1997/09/15 Caterpillar

Gas Admission Valve (GAV) Changed In Order To Provide For The Use Of Dial Indicator Settings{1102}

Usage:

G3606 (3XF52-Up),
G3608 (4WF38-Up),
G3612 (1YG81-Up),
G3616 (4CG56-Up) Engines

Reference: Systems Operation Testing And Adjusting, SENR4258, "Systems Operation Testing And Adjusting, G3606 And G3608 Engines."

Systems Operation Testing And Adjusting, SENR5528, "Systems Operation Testing And Adjusting, G3612 And G3616 Engines".

Description of Change: The GAV in the above engines has been changed in order to provide a new method of adjustment for the rocker arm. The new method of adjustment provides an indentation located on the back side of the rocker arm push rod leg. The indentation is provided in order to use a dial indicator for making adjustments.

Adaptable To: The rocker arm push rod legs with the indentation are effective with the above engines.

Setting The GAV With A Dial Indicator

1. Set the crankshaft position for valve lash settings. See the above references.

2. Set the dial indicator. The stem of the dial indicator should be in a parallel line with the line of travel on the rocker arm.

NOTE: Make SURE the rocker arm body is pressed snug to the left in order to indicate the maximum lash reading.

3. Rock the rocker arm assembly back and forth in order to measure the valve lash.

4. Adjust the valve lash with the adjustment screw. The setting should be .640 mm ± .010 mm (.0250 ± .0004 in).

5. After each adjustment, tighten the adjustment screw locknut to a torque of 30 N·m ± 4 N·m (22 ± 3 lb ft).

6. Check the adjustment again and repeat the above steps if necessary.

Caterpillar Information System:

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1997/09/15 New Dual Stage Torsional Coupling Assembly Available For Use With Twin Disc MG 514C Marine Transmissions{3357}

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1997/08/01 Guidelines For Electrically Grounding Gas Engines {7423}

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