帕金斯2806發動機氣門間隙如何調整方法

How to c heck/adjust the tappet clearances

Special requirements

Operation

Special tools		Tappet clearances
Description	Part number	Inlet	Exhaust
Engine turning tool	CH48	0,8 mm (0.05 in)	0,76 mm (0.00 in)

1

The tappet clearance is measured between the rocker levers and the top of the valve bridge pieces. The

operation must be done with the engine cold and stopped. Refer also to Operation -, How to check/adjust

the electronic unit injectors.

 

  Remove the rocker cover, Operation -.

2  Remove the cover (A2) from the flywheel housing. The top bolt (A) is the timing bolt.

Caution: If a customer-fitted speed sensor is fitted to the flywheel housing, it must be removed before the

engine turning tool can be inserted.

  Remove the plug (A) from the timing bolt location in the flywheel housing and fit the timing bolt.

Note: There are two locations for the timing bolt, one at each side of the flywheel housing. Use the location

that is the most convenient.

4  Insert the engine turning tool, CH48, into the fly wheel housing through the aperture behind the cover

(A2). Us e a  /2 inch drive ratchet with the turning tool to rotate the engine flywheel in the normal direction of

rotation (anti-clock wise when viewed on the flywheel) until the timing bolt engages with the threaded hole in

the flywheel. The piston of number  cylinder is now at TDC (top dead centre).

Caution: If the flywheel is turned past the threaded hole, the flywheel must be turned in the opposite direction

for approximately 45 degrees and then back in the normal direction of rotation until the timing bolt engages

with the threaded hole. This is  to eliminate backlash.

Continued

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5  Check the inlet and exhaust valves of the number  cylinder. If they are fully closed the piston is on its

compression stroke and the rocker levers can be moved by hand. If the rocker levers can not be moved

because the valves are slightly open, the piston is on its exhaust stroke. If it is on its exhaust stroke, withdraw

the timing bolt and turn the flywheel a further 60 degrees in the normal direction of rotation so that the number

 cylinder is set to TDC on its compression stroke, then insert again the timing bolt.

6 Before each set of tappet clearances is adjusted, ensure that the roller of the rocker lever is fully against the

camshaft lobe.

7 Use a set of feeler gauges, inserted at the position shown (B) between the valve bridge piece and the rocker

lever button, to c heck the tappet clearances for the inlet valves (C) on cylinders , 2 and 4. Adjust the

clearances if necessary. Check the tappet clearance for the exhaust valv es (C2) on cylinders ,  and 5, and

adjust the clearances if necessary.

Continued

Notes:

l  Move each valve bridge piece before the feeler gauge is inserted to reduce the effect of the oil film.

l  During the procedure, ensure that the feeler gauge is fully inserted

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8 After each unit has been adjusted, tighten the lock nut (B2) of the adjustment screw (B) to a torque of 0 +/

- 4 Nm (22 +/-  lbf ft).

9  Withdraw the timing bolt and rotate the flywheel by 60 degrees so that the number 6 piston is at TDC on

its compression stroke. Insert again the timing bolt into the threaded hole.

0  Check the tappet clearances for the inlet valves (C) on cylinders , 5 and 6. Adjust the clearances if

necessary. Check the tappet clearances for the exhaust valves (C2) on cylinders 2, 4 and 6, and adjust the

clearances if necessary.

  After each unit has been adjusted, tighten the lock nut of the adjustment screw to a torque of 0 +/- 4 Nm

(22 +/-  lbf ft).

2  Check again the tappet clearances for all six cylinders.

  Fit the rocker cover. Remove the engine turning tool and the timing bolt and fit the cover to the flywheel

housing. Fit the plug to the timing bolt location.