Sport aviation engines for Ultralights, Homebuilts, Kitplanes, Gyrocopters, Helicopters, Powered Parachutes, Trykes, Hovercraft & Air Boats.

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3503 water cooled 2 cycle 70hp

The 3503 produces 70hp at 6500 rpm while building an impressive torque of 57 ft lbs. at 6000 rpm. Operating in an Rpm range 1500 Rpm higher than the 60Hp 3502 results in much more thrust at full power for vehicles requiring more climb capability than cruise power as the 3502 is designed for. Fuel rate is 30-40% less than competing brands of 2 cycle engines in the same Hp range.

3503 incorporates Al-Nikasil coated cylinders for superior performance and reliability. Al-Nikasil in simple terms is a nickel based material, applied in a paste form, when super heated it becomes part of the cylinder itself. Al-Nikasil provides for a super low coefficient of friction, reducing engine heat and wear. The combination of Nikasil cylinders with water cooling render these engines immune from cold seizure, shock cooling or seizure from high EGT conditions. The pistons and cylinders expand at the same rate thus providing for a seizure resistant environment. 3503 crankshaft is 4130 chrome molly steel. Heads, cylinders, rings, block casting, connecting rods and associated components are all of the highest grade alloys available. With optional vertically mounted fuel injection 3502/03 can be used in compact engine compartments. Mounting bolt pattern is identical to the R-582.

Factory recommended TBO is rated at 1000 Hrs. @ 75% power.

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Dual Carb Recoil Start
$6327.00
Dual Carb Electric Start
$7021.00
Dual Carb Recoil Start with Gear Box
$7551.00
Dual Carb Electric Start with Gear Box
$8253.00
Oil Injection Option
$259.00
Electronic Fuel Injection Option
$1591.00



Special Design - High Torque/Low Rpm - fuel efficient Engine

Model:
3503
Engine Type:
2 cycle, two cylinder in line
Bore:
76mm
Stroke:
69mm
Displacement:
625cc
Compression:
9.5:1
HP Output:
70hp @ 6500rpm
Torque:
57ft/bs @ 6000rpm
Ignition:
Dual CDI
(Capacitive digital Ignition)
Carburation:
Dual 34mm slide or optional electronic fuel injection
Fuel Pump:
Auxiliary external pneumatic - 12VDC with fuel injection
Lubrication:
Fuel mixed with oil @ 50:1 /Blue Max @100:1 or optional oil injection
Rotation:
Counter clockwise, viewed from output end-Gearbox reverses direction
Starter:
Alternator:
12 volt electric, recoil or both
250 watt/20 amp alternator standard
Cooling:
Liquid cooled.
Weight:
79 lbs-not including radiator & coolant. Optional gearbox adds 19 lbs.
Reduction Units:
G-50 gearbox available in 2.16:l, 2.29:l, 2.59:l, 3.16:l and 3.65:l ratios. Cog belt belt drive also available.
Drive Coupling:
Elastomeric dampener or optional centrifugal clutch.




Engine Print Side View


Engine Print End View

 

Exhaust System Print

 

Customer Photo Gallery




3503 installed in ParaSki PPC
Picture #1 Picture #2
Picture #3