
Specifications—300R HD
300R HD MODELS
Attribute
300R HD
Horsepower
300
Kilowatts
221
Full throttle RPM range
5800–6400
Idle RPM in neutral gear*
600
Idle charge compensation**
600–725
Troll control RPM limit
550–1000
Number of cylinders
8
Displacement
4.6 Liter
4,576 cc (279.2 cid)
Cylinder bore
92 mm (3.62 in.)
Stroke
86 mm (3.38 in.)
Spark plug
NGK LKAR7C‑9
Spark plug gap
0.9 mm (0.035 in.)
Spark plug hex size
14 mm
Sport Master ratio
1.75:1
137 mm (5.4 in.) ratio
1.75:1
Gearcase
capacity
Sport Master
RH, LH
620 mL (21.0 fl oz)
137 mm (5.4
in.) RH
720 mL (24.4 fl oz)
137 mm (5.4
in.) LH
680 mL (23.0 fl oz)
Recommended gasoline
Refer to
Fuel and Oil
Recommended oil
Refer to
Fuel and Oil
Engine oil capacity with oil
filter replacement
6.6 Liter (7.0 US qt)
Required battery type
12‑volt absorbed glass mat (AGM) battery
Battery
type***
USA (SAE)
800 minimum marine cranking amps (MCA)
with a minimum reserve capacity of 135
RC25 rating
International
(EN)
975 minimum cold cranking amps (CCA) with
a minimum 65 amp hour (Ah)
GENERAL INFORMATION
eng
17
Summary of Contents for 300R HD CMS Mechanical
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