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What we have up for offers here is a good used and excellent running 2-cycle twin cylinder fan cooled, oil injected, 53hp Rotax 503 engine with accessories as shown below. IF YOU MISSED OUR LAST 503 ENGINE, HERES YOUR CHANCE TO GET ANOTHER GREAT ENGINE! This engine would be the perfect choice if you are looking for a good used good used 50-55hp horsepower engine for any of your homebuilt projects including ultralights, hovercraft, airboats, gyros, PPC\'s, trikes, golf carts, land based applications or other projects requiring this horsepower range. If you have been looking for a replacement for your 447 or maybe just want to upgrade to 503 for your build I think you will find OUR 503 Rotax engine package to be a great choice! Engine is in good cosmetic and great mechanical condition and ready to mount and use. Now here is the full specs and whats included with the engine.

ENGINE SPECS: Model: 503 Rotax DCSI provisional-4 496cc twin cylinder fan cooled oil injected 2-stroke. Bore is 72mm and the stroke is 61mm. Cubic inches is rated at 30.3. Compression is 10.8-1. Horsepower is factory rated at 50-53hp at 6800 rpms in the dual carb version..
IGNITION: Engine is currently set-up running the single Nippendenso CDI(electronic) ignition system...Magneto has both generator and lighting coils with AC 12V 170W output.
CARBURATION/FUEL: Fuel intake is via two Mikuni 36mm round slide carb which is pneumatically feed from a dual outlet Mikuni fuel pump. Carb is equipped with a provisional for a hand/remote primer. Engine is also fitted with a factory Rotax oil injection set-up. No more pre-mixing your fuel.
COOLING: Cooling is provided via the axial fan and direct air flow across the engine.. Engine can also be ran as a free-air model.
BASE ENGINE DATA: Engine case is all aluminum with the cylinders being a lightweight aluminum alloy with cast iron cylinder sleeves.
PTO/DRIVE: PTO is the industry standard 30mm 1.125 tapered. Engine case is provisional-4 will take the early Rotax A and B boxes, along with belt reductions, direct bolt prop hubs, coupler\'s and power transmission\'s set-up for this configuration. PTO spins counterclockwise as viewed looking directly down on the end of the engine.
WEIGHT/SIZE: Engine weighs 67 pounds as shown below with no electric start or drive. Engine sizing is as follows, 14\" from the bottom of the engine to the top of the spark plugs, 17\" in length from the outside of the pull starter to the tip of the PTO and 12\" deep from the intake of the carb to end of the fan tower.
MOUNTING/APPLICATION: This model engine is equipped from the factory with a four hole arrangement on the bottom of the of the engine. This pattern will allow for motor plates, root tube set-ups and many other configurations for mounting. Engine can be ran and mounted in both the inverted, horizontal or vertical positions. It can also be ran in both tractor and pusher applications.
STARTING: Engine is fitted with the standard pull/recoil starter, but GPL and Rotax electric start kits are available for this engine that we stock(GPL\'s only) in house..
APPLICATIONS: This 503 would make a great choice for any of your ultralight, hovercraft and airboat fields, but also would work out great in a ton of other land and water based applications.
CONDITION: Engine is in excellent running condition and needs nothing. Compression checks out at 125+ with the engine also having excellent spark. Some light cosmetic wear here and there and a little oxidation around the mount holes and such but not effecting use and nothing serious.(BELOW I HAVE ATTACHED 8 PICTURES OF THE ENGINE/ETC TO GIVE YOU A BETTER IDEA OF THE COSMETIC CONDITION). Engine is ready to bolt up and use on any application.
