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3503 water cooled 2 cycle 70hp
 

Dual Carb 
Recoil Start

$5988.00

Dual Carb 
Electric Start

$6600.00

Dual Carb 
Recoil Start 
with Gear Box

$7213.00

Dual Carb 
Electric Start 
with Gear Box

$7745.00

Oil injection option

$232.00

Electronic Fuel Injection Option

$1430.00

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.

Model:

3503

Carburation:

Dual 34mm slide or optional electronic fuel injection

Engine Type:

2 cycle, two cylinder in line

Fuel Pump:

Auxiliary external pneumatic - 12VDC with fuel injection

Bore:

76mm

Lubrication:

Fuel mixed with oil @ 50:1 /Blue Max @100:1 or optional oil injection

Stroke:

69mm

Rotation:

Counter clockwise, viewed from output end-Gearbox reverses direction

Displacement:

625cc

Starter:
Alternator:

12 volt electric, recoil or both
250 watt/20 amp alternator standard

Compression:

9.5:1

Cooling:

Liquid cooled.

HP Output:

70hp @ 6500rpm

Weight:

79 lbs-not including radiator & coolant. Optional gearbox adds 19 lbs.

Torque:

57ft/bs @ 6000rpm

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.

Ignition:

Dual CDI
(Capacitive digital Ignition)

Drive Coupling:

Elastomeric dampener or optional centrifugal clutch.

Click here to view engine print side view.

Click here to view engine print end view.

Click here view to exhaust system print.

Picture of 3503 exhaust side of engine  

Picture of 3503 intake side of engine

Picture of 3503 bottom view of engine

Picture of 3503 installed in ParaSki PPC pic#1. pic#2. pic#3.

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