BRP Johnson 4HP, Service Manual, Page: 20 / 185

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GENERAL INFORMATION
*SPECIFICATIONS
Item Unit
Data
4 HP 5 HP 6 HP
ELECTRICAL
Ignition timing Degrees BTDC 3° – 28°
Over revolution limiter r/min 6000
Ignition coil resistance Secondary
k
Ω
at 20°C
8.4 – 12.4 [H.T.cord – pulser core]
Spark plug cap resistance
k
Ω
at 20°C
7.5 – 12.5
Battery charge coil resistance (Optional part)
Ω
at 20°C
0.6 – 1.0 [R – Y]
Battery charge coil output (12V) (Optional part)
AMP
6-7
Standard spark plug Type NGK BPR6ES
Gap mm (in) 0.7 – 0.8 (0.028 – 0.031)
GEARCASE
Design specification thickness for shim and washer
Pinion gear backup shim mm (in) 2.0 (0.08)
Forward gear backup shim mm (in) 1.2 (0.05)
Forward gear thrust washer mm (in) 1.0 (0.04)
Reverse gear thrust washer mm (in) 1.0 (0.04)
Reverse gear backup shim mm (in) 0.8 (0.03)
Initial selection-shim adjustment may be required.