I've been working on mounting the 618 to the Kitfox.

If you have a 582 you might consider swapping out to one of the larger Rotax 2 cycle engines. Here are the things that I've found doing the swap on my plane.

First the mag end bell housing is slightly longer than the 582. Also the total height is a little taller. This introduces the problem of needing to shim the engine up to clear the bell housing but not hitting the spark plugs on the cowling.

Step 1, shim the engine mount further from the firewall.
-I used four AN washers between the mount and the firewall this was perfect and allowed the engine to slip in snug but not tight!


Step 2, shim the engine up with found 1/4 inch thick pieces of aluminum or steel. If using aluminum you'll need to use a washer so as to not have the aluminum only bearing the engine weight against the steel engine mount. Over time the aluminum being soft will deform without a washer to provide a harder metal contact point. I used a large washer to spread the load over the aluminum shim evenly. I also added a second washer just to make the bell housing fit with a little more room. You'll need to get longer bolts to make this all work as a result. You can use the short bolts to get everything lined up and then swap them out so you don't mess up the threads in the process.


Step 3, mount the exhaust, (I'm on this step now and will provide pics with the exhaust hung.


Step 4, hook up to gauges, throttle, choke, electrical and radiator. Everything is the same as your 582. Mount the prop on the gearbox.

Step 5, Run her up and set the prop pitch for max static RPM of 6200. This should be a good climb and cruise as well as give you buffer if full power and not be right at red line. Red line on the 618 is 6800. I don't like to go over 6500.