Yanmar 4TNV98, Service Manual

Page: 70 / 246

4TNV98 & 4TNE98 Diesel Engine Section 3. Engine 68
Push Rod
Inspection Item Standard Limit
Reference
Page
Page Push Rod Bend
Less than
0.0012 in. (0.03 mm)
0.0012 in.
(0.03 mm)
See Push
Rod Bend
on page 93.
Rocker Arm and Shaft
Inspection Item Standard Limit
Reference
Page
Arm Shaft Hole Diameter
0.7283 - 0.7291 in.
(18.500 - 18.520 mm)
0.7311 in.
(18.57 mm)
Shaft Outside Diameter
0.7272 - 0.7280 in.
(18.470 - 18.490 mm)
0.7260 in.
(18.44 mm)
Oil Clearance
0.0004 - 0.0020 in.
(0.010 - 0.050 mm)
0.0051 in.
(0.13 mm)
See
Inspection of
Rocker Arm
Assembly on
page 93 and
94.
Valve Spring
Inspection Item Model Standard Limit
Reference
Page
4TNV98 (4-Valve Head)
1.5630 in.
(39.7 mm)
1.5433 in.
(39.2 mm)
Free Length
4TNE98
1.87 in.
(47.5 mm)
-
4TNV98 (4-Valve Head) -
0.0551 in.
(1.4 mm)
Squareness
4TNE98 -
0.05 in.
(1.2 mm)
See
Inspection of
Valve
Springs on
page 97 and
101.
Camshaft and Timing Gear Train Specifications
Camshaft
Inspection Item Standard Limit
Reference
Page
End Play
0.0020 - 0.0079 in.
(0.05 - 0.20 mm)
0.0118 in.
(0.030 mm)
See
Removal of
Camshaft on
page 114.
Bend (1/2 the dial gauge reading)
0 - 0.0008 in.
(0 - 0.02 mm)
0.0020 in.
(0.05 mm)
4TNV98
1.7087 - 1.7165 in.
(43.400 - 43.600 mm)
1.6988 in.
(43.150 mm)
Cam Lobe Height
4TNE98
1.6707 - 1.6758 in.
(42.435– 42.565 mm)
1.6608 in.
(42.185 mm)
See
Inspection of
Camshaft on
page 125.
Shaft Outside Diameter / Bearing Inside Diameter