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  Electric Motors, Engines & Accessories > Engines Glow Fuel > Engines R/C Glow Fuel Marine 2-Stroke - .20-.40 Bookmark this Page

O.S. - OSMG1622 OSM13952 13952 531028022355 4531028022355
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O.S. 21XZ-M Speed 3.5cc Inboard Marine Engine
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O.S. 21XZ-M Speed 3.5cc Inboard Marine Engine
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Tower Catalog Page: 197

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Tech Notes
            This is the O.S. Speed 21XZ-M Inboard Marine Engine.

****** Because of the competition nature of this engine,****** ******it is NOT covered by the O.S. 2 Year Warranty.******

FEATURES: DLC (Diamond-like Coating) on crankshaft, plus tungsten weights to minimize vibration, and silicone inserts to smooth fuel mixture 21D big-bore carburetor allows the use of high nitro fuel Laser engraved water cooled cylinder head

INCLUDES: 21XZ-M Speed Inboard Marine Engine with RP7 Glow Plug, Exhaust Seal Ring, Dust Cap, Head Gasket Set and Instruction Manual

REQUIRES: Fuel: Boat blend with 10-30% nitro content (20% recommended for break in) Exhaust system depending on application Glow starter and shore equipment

SPECS: Displacement: 0.213 cu in (3.49 cc) Bore: 0.641" (16.27mm) Stroke: 0.661" (16.8mm) Practical RPM: 4,000-45,000 Output: 2.76 hp @ 33,000 RPM Weight: 10.85 oz (307.5 g) Crankshaft Size: 1/4-28 Carburetor Settings: Needle Valve; Turn clockwise until closed, open 1.5 turns, close 10-15 after running hull through 1 tank of fuel, repeat until approximately 2 liters of fuel have been consumed Mixture Control Valve; After getting needle valve adjusted, turn clockwise or counterclockwise in 10 increments to reduce excessive smoke (too rich) or to reduce speeding up momentarily (too lean)

Distance between mounting hole centers same side: 0.83" (21mm) Distance between mounting hole centers opposite side: 1.4" (37mm) Distance/mounting tab to center of exhaust: 1.1" (28.5mm) Distance/mounting tab to center of cooling inlet: 2.2" (55.05mm) Distance from exhaust center to mounting flange bottom: Width not including mounting flanges: 1.2" (31.6mm) Width including mounting flanges: 1.8" (45mm) Height bottom of crankcase to top of intake: 3.1" (78mm) Length from Front Bearing/end of Crankshaft: 0.87" (22mm) Length from Front Bearing/center of Crankcase: 1.7" (44mm) Length from Center of Crankcase/end of Crankshaft: 2.6" (66mm)

jxs 12/03/12 ir/jxs

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Accessories Needed
This is the O.S. Speed 21XZ-M Inboard Marine Engine. FEATURES: 21D big-bore carburetor allows use of high nitro fuel, Diamond Like Coating on silicone filled tungsten weighted crankshaft for optimum balance, RP7 turbo glow plug, laser etched water cooled head REQUIRES: 10-30% nitro boat fuel, glow starter, shore equip.

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 LXZUK6 AquaCraft GrimRacer 30% Boat Fuel Quart
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