New Holland 40 Series Repair Manual page 30

- - - - - - - - - - PART 1 - ENGINE S Y S T E M S - - - - - - - - - -
Cylinder Head Flatness
1. Straight Edge 2. Feeler Gauge
4. Using a special tool with a straight edge
and feeler gauges, check flatness of cyl-
inder head in all directions does not ex-
ceed,
0.001 in (0.03mm) in any 1 in (25.4mm),
or 0.005 in (0.127mm) overall limit,
Figure 12.
5. If the cylinder head has been resurfaced,
determine that all head bolt faces will seat
by placing the cylinder head less gasket,
on the cylinder block and installing the
cylinder head bolts hand tight.
6. Ensure rocker shaft supports are fitted
with long bolts. Using a feeler gauge,
check clearance between underside of
bolt heads and cylinder head or rocker
shaft support.
7. If a 0.010 in (0.25mm) feeler gauge can
be inserted under the bolt head the bolt
has bottomed. TherefOrE3 the cylinder
block thread must be Increased usrng a
9/16-13 UNC-2A Thread
tap.
Identify
the bolt heads and ensure they are rein~
stalled in the bolt holes they were
checked in.
VALVE INSERTS
13
R1-11
Valve Seat Dimensions
1. Valve Seat Angle
2. Valve Seat Width
3. Valve Head Face to Cylinder Head Depth
NOTE: Refacing the valve seat should al-
ways be co-ordinated with refacing of the
valve to ensure a compression tight fit.
1. Examine the valve seat inserts and reface
if pitted, renew if loose or damaged.
2. To install a new valve insert, the cylinder
head must be counter bored, as dimen-
sioned in the chart below. The new insert
must be chilled in dry ice prior to installa-
tion.
Counter Bore in Cylinder Head
Insert Oversize
Exhaust valve insert
Intake valve insert
0.010 in (0.25mm) 1.739-1.740 in (44.17-44.20mm)
1.969-1.970 in (50.01-50.04mm)
0.020 in (0.58mm) 1.749-1.750 in (44.42-44.45mm) 1.979-1.980 in (50.27-50.29mm)
0.030 in (0. 76mm) 1.759-1.760 in (44.68-44.70mm) 1.989-1.990 in (50.52-50.55mm)
12