Onan NH User Manual

Dimensions and Clearances
All clearances given at room temperature of 7OoF (21OC) . All dimensions in inches (approximate millimetre dimensions in
parentheses) unless
otherwise specified .
DESCRIPTION
CYLINDER BLOCK
Cylinder Bore Honed Diameter .......................................
Maximum Allowable
Taper
...............................................................
Out-of-Round .......................................................
Main Bearing Inside Diameter (Without bearing) .....................
Main Bearing Inside Diameter (Installed) ..............................
Camshaft Bearing Bore (Bearing installed) ...........................
CRANKSHAFT
Main Bearing Journal Diameter .......................................
Main Bearing Clearance ..........................................
Connecting Rod Journal Diameter ...................................
Crankshaft End Play ..................................................
CONNECTING ROD
Large Bore Diameter (Without bearing installed
and rod bolts properly torqued
.....................................
Connecting Rod Side Clearance ......................................
Piston Pin Bushing Bore (Without bearing) ...........................
Piston Pin Bushing Bore with Bearing.
(Finished bore)
.....................................................
Bearing to Crankshaft Clearance
Nodular iron Rod
...................................................
Aluminum Rod ......................................................
CAMS HAFT
Bearing Journal Diameter ............................................
Bearing Clearance ....................................................
End Play ..............................................................
Camshaft Lift .........................................................
PISTON
Clearance in Cylinder
Measure
90° to pin 0.10 inch below oil ring
Strut Type Spec A-C
.............................................
Without Strut Begin Spec D ......................................
Piston Pin Bore .......................................................
Ring Groove Width
Top
1 Compression Ring Spec A-C ................................
Top 1 Compression Ring Begin Spec D ............................
No . 2 Compression Ring Spec A-C .................................
No . 3 Oil Control Ring ..............................................
No . 2 Compression Ring Begin Spec D .............................
MINIMUM
Inches
(mm)
3.5625 (90.49)
2.1 87
(55.55)
2.001 5 (50.84)
1.3760 (34.95)
1.9992 (50.78)
0.0025 (0.064)
1.6252 (41.28)
0.005 (0.13)
MAXIMUM
Inches
(mm)
3.5635 (90.51)
0.003 (0.08)
0.003 (0.08)
2.1 88 (55.58)
2.0040 (50.90)
1.3770 (34.98)
2.0000 (50.80)
0.0038 (0.097)
1.6260 (41.30)
'
0.009 (0.23)
1.7505 (44.46)
1.751
0 (44.48)
0.0020 (0.051)
0.0160 (0.406)
0.8115 (20.61)
0.8125 (20.64)
0.7504
(1 9.06) 0.7508 (1 9.07)
0.0005 (0.013)
0.0028 (0.071)
0.0020 (0.051)
0.0033 (0.084)
1.3740 (34.90)
1.3745 (34.91)
0.0015 (0.038)
0.0030 (0.076)
0.0030 (0.076)
0.0120 (0.305)
0.300 (7.62)
0.001
5 (0.038)
0.0035 (0.089)
0.0070 (0.178)
0.0090 (0.229)
0.7502 (19.055)
0.7506 (19.065)
0.0955 (2.426)
0.0965 (2.451)
0.080 (2.032)
0.081 (2.057)
0.0955 (2.426)
0.0965 (2.451)
0.080 (2.032)
0.081 (2.057)
0.1 88 (4.775)
0.1 89 (4.801)
4

Onan NH Specifications

General

Engine Model	NH
Cylinders	2
Fuel Type	Gasoline
Governor Type	Mechanical
Ignition System	Battery
Starter	Electric
Engine Type	4-cycle, air-cooled