TP-5867 11/02 3Section 1 Specifications
Engine Specification 8.5RMY (60 Hz) 11RMY (60 Hz)
Manufacturer Kohler
Model CH20 CH25
Cycle 4
Number of cylinders 2
Compression ratio 8.5:1 9.0:1
Displacement, cc (cu. in.) 624 (38.0) 725 (44.0)
Rated horsepower (propane fuel) 12.3 (16.5) 14.6 (19.6)
Rpm 3600
Bore x stroke, mm (in.) 77 x 67 (3.03 x 2.64) 83 x 67 (3.27 x 2.64)
Valve material
Steel/Stelliter
Cylinder block material Aluminum w/cast iron liners
Cylinder head tightening torque, Nm (ft. lb.) 30 (40.7)
Cylinder head material Aluminum
Piston rings 2 compression/1 oil
Crankshaft material Heat treated, Ductile Iron
Main bearings: number, type 2, parent material
Governor Electronic
Lubrication system Full pressure
Oil capacity (w/filter), L (qt.) 1.9 (2.0) 2 (2.1)
Oil pressure, kPa (psi) 172-- 241 (25--35)
Fuel system LP gas or natural gas
LP/natural gas minimum supply pressure,
in. H
2
O (oz./in.
2
)
7--11 (4--6)
Battery voltage 12 VDC
Battery ground Negative
Spark plug gap, mm (in.) 0.76 (0.030)
Spark plug tightening torque, Nm (ft. lb.) 24.4/29.8 (18/22)
Ignition system Capacitor Discharge
Smart Spark Capacitor Dis-
charge
Starter motor cranking current at 70_ F Electric, solenoid shift
Cooling system Air-cooled
Figure 1-3 Engine Specifications
1.6 Service Views
This section includes two generator set service views.
See Figure 1-4 and the descriptions below to determine
which service view applies to your generator set.
Figure 1-5 shows a single-fuel generator set, which can
be identified in two ways:
D Single-fuel model specification numbers begin with
PA-. See the generator set nameplate for the spec
number.
D Single-fuel models have the fuel valve shown in
Figure 1-5.
Figure 1-6 shows a multi-fuel generator set, which can
be identified in two ways:
D Multi-fuel model specification numbers begin with
GM. See the generator set nameplate for the spec
number.
D Multi-fuel models have the fuel block shown in
Figure 1-6.
Spec Number
Format
Fuel System Service View
PA-xxxxxx Single-fuel Figure 1-5
GMxxxxx Multi-fuel Figure 1-6
Figure 1-4 Service View Identification