rotax 582

[lbrunet 0]

I am considering what engine i would go with on the mohawk airframe.  The manual suggest 503, - 582.  I never flew behind a 2-stroke engine.  I would go with the 582 if any.  Are they reliable, what is tbo? ect.

[1avidflyer 1983]

Lots of guys have flown behind the 582.  Makes very good power for the weight.  Rotax calls for rebuild at 300 hrs.  Two strokes are very sensitive to tuning.  To lean makes for a quiet engine in short order.   Run correctly, they can be a fairly reliable engine.  One of our members here flew his Avid with a 582 from coast to coast, and another flew over the Rockies from Ca. to Id.  on several occasions.  Lots of shorter trips as well of course.   JImChuk

[109jb 181]

I wasn't a 2-stroke fan on airplanes and then I bought an airplane with one. A 582 in fact.  I still prefer 4-stroke, but have no problem with 2-strokes anymore.  BTW, I've always had 2-stroke snowmobiles and several 2-stroke motorcycles over the years. The key i found is to do a few things.

1. Warm up every time. Don't take off until water temp is at least 140

2. Maintain proper jetting for conditions.

3. Keep an eye on the temps, particularly EGT

4. Use a thermostat

5. Don't do descents where you push the nose over with significant power on it. This will cause the engine to lean out and EGTs will climb rapidly. Better to do a chop and drop.

6. When doing the chop and drop as in #5, keep an eye on the water temp. If the temp drops too low, then level off, bring the power back in and let the temp come up.  Only really a factor in cold temps if you don't have what I'm describing next.

7. I wound up removing the thermostat from the head and using an inline thermostat with a bypass through the cabin heater core. This worked great and kept the temps where they needed to be. When cold, coolant would only circulate through the heater core, but when it heated up it allowed flow to the main radiator.

Basically they just aren't as tolerant of using them wrong, but if you know a few things you can keep them in line pretty easily.

[lbrunet 0]

Thanks so much for the tips.  I like the power to weight ratio.  Ha! i flew behind a onan in a quickie for three years.  thanks again. 

[Av8r_Sed 82]

109jb hit the nail on the head with his description. The only thing I would add is that a mixture control is very beneficial. It allows you to set the EGTs at an optimal level for the phase of flight you’re in and somewhat reduces the need to rejet for seasonal changes.

Sure, I’d like a 912 on my Model III, but I can’t justify that investment unless I start flying a lot more hours (fuel burn is higher 582 vs 912). 

[lbrunet 0]

i have not seen a carb. heat on a 582.  The carb heat on my onan quickie saved my butt twice.  What do ya'll do for carb heat. 

[Av8r_Sed 82]

No carb heat for me. I’ve never heard of anyone doing it for a 582.  It has been said that the Bing 54 slide valve carbs aren’t as prone to forming carb ice as other types, but you’ll have to do your own research on that. 

In all honesty, if you’re flying behind a two stroke you’ll have to be even more vigilant for the possibility of an engine out than you normally would. Carb ice is one of many things that might have you landing out somewhere.