Camshaft, Tappets And Valves Checks, Measurements And Repairs - New Holland TD60D Repair Manual

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SECTION 10 − ENGINE − CHAPTER 1
CHECKS, MEASUREMENTS AND REPAIRS −
CAMSHAFT, TAPPETS AND VALVES
WARNING
Handle all parts carefully. Do not put your hands or
fingers between parts. Wear suitable safety clothing,
safety goggles, gloves and footwear.
Clean all parts carefully before carrying out the
following operations.
Valves
Use tool 380000302 for valve removal and installa-
tion.
In the case of minor sealing faults, the valves and
their seats in the cylinder head may be re−faced
using a pneumatic grinder or universal grinder. In
case of more serious defects, re−face the seats and
grind the valves as shown in the relative chapter.
After grinding, check that the step below the valve
contact band is no less than 0.5 mm (0.02 in.).
Dimensions (mm) of valves and valve guides
A. Intake.
B. Distance to be obtained by reaming fitted valve
guide.
S. Exhaust.
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Tappets
Check that the tappets slide freely in their bores
without excessive play.
In the case of excessive tappet−to−bore clearance,
rebore the seats and fit oversize tappets (see page
20).
Pushrods must be perfectly straight, and the con-
cave contact surface with the rocker arm adjuster
screw must not show signs of seizure or excessive
wear, otherwise the rod must be replaced.
In case of refacing of the contact surfaces, remove
as little material as possible.
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603.54.471.00 − 11 − 2004