Motor Cat

Motor 3406C
Bridge Adjustment
When the head is disassembled, keep the bridge with their respective cylinders. Adjustement of the
bridge will be necessary after the valves are ground or other reconditioning of the cylinder head is
done. The bridge should be checked and / or adjuted each time the valves are adjussted. To check for
wear use a dial indicator to measure the amount of wear on thebridge seat. Make sure the contact point
on the dial indicator is small enough in diameter to get an accurate measurement.
Use the bridge again if the wear is 0.13 mm (.005 in ) or less. When the wear seat is worn more than
the allowable limit, the worn surface of the seat can be ground flat. The maximum amount of material
that can be removed is 0. 38 mm (.015 in ) . If the seat cannot be madeflat, replace the bridge.
Reconditioning of the wear seat can only be done once.
Use the procedure that follows to make an adjustment to the bridge.
Note: Valves must be fully closed.
1.Put engine oil on the bridge dowel in the cylinder head and in the bore in the bridge.
2.Install the bridge with the adjustment screw toward the exhaust manifold.
3.Loosen the locknut for the adjustmentscrew and loosen the adjustment screw several turns.
4.Put a force on the bridge with a finger to keep the bridge in contact with the valve stem oppsite the
adjustment screw.
5.Turm the adjustment screw clockwise until it just makes contact wirt the valve stem. The turn the
adjustment screw 30 degrees more in a clockwisse direction to make the bridge straight on the dowel,
and to makecompensation for the clearance in the threads of the adjustment screw.
6.Hold the adjustment screw in this position and tighten the locknut to 30 ± 4 N.m (22 ± 3 ft).
7.Put engine oil at the point where the rocker arm makes contact with the bridge.

Valve Lash Setting
Note: Valve lash is measured between the rocker arm and the rocker arm and the bridge for the valves.
VALVE LASH CHECK: ENGINE STOPPEDExhaust

0.69 to 0.84mm (.027 to .033 in )

Inlet

0.30 to 0.46 mm (..012 to .018 in)

Note: When the valve lash is checked, adjustment is not necessary if the measurement is in the range
given in the cart for Valve Lash Check: Engine Stopped. If the measurement is outside this range,
adjustment is necessary. See the chart for Valve Lash Setting: Engine stopped, and make the setting tothe nominal ( desired) specification in thes chart.
VALVE LASH SETTING: ENGINE STOPPED
Exhaust

0.76mm (.030 in )

Inlet

0.38mm (.015 in)

To make an adjustment to the valve lash, turn the adjustment screw in the rocker arm. Valve lash the
adjustment can
be made by using the procedure that follows:
1.Put No. 1 piston at top center (TC) on the compression stroke. Make rererence toFinding Top Center
Compression Position For No. 1 Piston.
2.Make an adjustment to the valve lash on the inlet valves for cylinder 1,2 and 4. Make an adjustment
to the valve lash on the exhaust valves for cylinders 1, 3, and 5.
3.After each adjustment, tighten the nut for valveadjustment screw to 30 ± 4 N.m (22 ±3 lb ft ), and
check the adjustment again.
4.Remove the timing bolt and turn theflywheel 360 degrees in direction of engine rotation. This will
compression stroke. Intall the timing bolt in the flyweel.
5.Make an adjustement to the valve lash on the inlet valves for cylinder 3, 5, and 6. Make an
adjustment to the valve lash on the exhaust valves for cylinders 2,4, and 6.
SISTEMA COMBUSTIBLE
5

4

3

2

1

Ajuste del Puente
Cuando la cabeza está desmontada,mantenga el puente con sus respectivos cilindros. La calibracion
del puente será necesario después que las válvulas son cortadas o renovadas, de la cabeza del cilindro
. El puente debe ser inspeccionado y / o ajstado cada vez que las válvulas sean ajustadas. Para
comprobar el desgaste debe utilizar un indicador para medir la cantidad de desgaste en el asiento del
puente. Asegúrese de que el punto...