General Specifications
HP / kW
15 HP / 11.2 kW
Displacement
302 cc (18.4 cu in.)
Cylinders
2 (Inline)
WOT RPM
5400 - 6000
Weight
44 kg / 97 lbs
Drive & Lower Unit
Gear Ratio
2.42
Shaft Length
15", 20"
Electrical System
Alternator Output 145 Watts
Starting System Manual
Technical Maintenance Toolkit
Verified service specifications for the Johnson 15hp (4-Stroke) (2005)
Lubrication
Engine Oil
10W-30 Marine
Oil Capacity 1 Liters
Gearcase Lube 170 ml
Ignition System
Spark Plug
NGK CR6E
Gap Setting 0.75mm
Firing Order 1-2-3-4
Performance Specs
Idle RPM 700 ± 50
WOT Range 5400-6000
Alternator 145W
Standard Maintenance Intervals
20H Break-in Service
100H Annual Tune-up
300H Water Pump & Seals
Identification
The serial number for the Johnson 15hp (4-Stroke) is typically found on a plate located on the transom bracket.
Technical Toolkit
Maintenance Compatibility
These models share common service parts with the Johnson 15hp (4-Stroke):
Model Evolution
History of the Johnson 15HP series over the years:
Category Discovery
Reference Data
Information compiled from Johnson Marine factory service manuals and original sales literature published in 2005.