Richard Sementilli wrote:
>
>Thank you for your email.
>1. Yes, I've heard about the bumpy starts and stops with the 912S
>motor. I also heard that the new ones are equipped with a stronger
>starter motor that powers through the high compression starts, have
>you heard this? I aslo read another email here on the Europa list that
>claims wonderful performance even at altitude with the 912S...I'm so
>confused!!!
>
>
There was a change to beefier anti-servo tab drive pins (with associated
'recall' and retrofit) because drive pins were being sheared off during
rough starts. We are NOT the only ones with damage due to hard starts.
We also get about 200 fpm climb at 12,000'+. I would like more when
climbing to 14,500' to clear the mountains, especially with the
turbulence, rotors, etc. that exist in these areas. A 914 would give
more margin.
>2. I intend to fly it mostly on the east coast but I do intend to take
>it to Lake Tahoe too so I was hoping to get through the mountains with
>the 912S. I would buy the 914 turbo but I am afraid of the reliability
>and complexity of the engine.
>3. I have never heard about the mixture issue, is that common?
>
>
Yes, we get about the same mileage at 10,000+ feet as at sea level, as
reported by others. Having paid in time and fuel for the climb to
altitude, you should be able to get better mileage when you get there.
You do with the 914, not the 912S. You decide if it matters.
>4. Never heard about the gear box wear due to the bumby idle either.
>
>
This is what we were told by Lockwood. I have heard it elsewhere. I
also have had such problems with a rented Katana (Rotax 912 powered),
with a damaged gear box, presumably from rough starts and/or low idle.
>Is their any solution to this while still using the 912S?
>
>
We were told to keep the idle speed up, that is the solution.
>
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>>
>>Hi Richard,
>>
>>You didn't say where you do your flying. If you intend flying at
>>altitude like we do around the Sierra Nevadas, you might consider the
>>914 the best bet.
>>We have a mono-wheel XS with 912S and Airmaster prop. I would seriously
>>consider installing the 914 or Jabiru over the 912S, given our
>>experiences (we have over 400 hours on the plane/engine).
>>Issues I have with the 912S are:
>>
>>1) It shakes the whole plane when starting and stopping, causing great
>>stress on any number of componants. Our exhaust system is in constant
>>need of repair because of this. An ignition wire probably broke because
>>of this. Standing outside the uncowled engine and watching the extreme
>>travel of the shaken componants can be a real eye opener. It is not
>>unusual to see +2G/0G on the panel mounted accelerometer following a
>>start or stop. I would guess the 912S is worse than the 914 because of
>>its higher compression. I would expect the Jabiru to be much smoother.
>>
>>2) The 912S is a little anemic at high density altitudes. At 7,000+
>>feet the plane has difficulty accelerating past 55 knots on take off
>>until the gear/flaps are lifted a little. Climb rate at these altitudes
>>can also be lower than I would like.
>>
>>3) The mixture becomes rich at altitude, negating the fuel economy
>>advantages of flying at altitude. The 914 is altitude compensating, and
>>I assume the Jabiru has a mixture control (?).
>>
>>4) Although the Rotax is claimed to have a TBO of 1000 hours or greater
>>it is recommended that the gearbox be removed and sent in for check out
>>every 300-400 hours. There have also been suggestions that idling the
>>912S down to 1400 rpm can cause damage to the gearbox due to rough
>>idling. We idle our engine at about 1700-1800 rpm, which make the
>>landings a little hotter with the additional idle thrust.
>>
>>just my two cents worth,
>>regards,
>>Terry Seaver
>>A135 / N135TD
>>
>>Richard Sementilli wrote:
>>
>>
>>
>>>
>>>I am down to 3 choices for an engine for my Europa.
>>>1. Rotax 912S
>>>2. Rotax 914
>>>3. Jabiru 3300
>>>
>>>I would like to get objective opinions and actual experiences from
>>>anyone about the pro's and cons of each engine.
>>>My first choice is the 914 because of the all around performance but
>>>more than the huge price, I am worried about the complexity of the
>>>engine as it relates to maintenance and overall reliability. I have
>>>spoken to a few mechanics for Rotax but none of them have any
>>>experience with the 914 turbo. They all say to keep it simple and go
>>>with the 912 or the 3300. I agree but I'm willing to stretch that goal
>>>if feel that I could handle the burden of its complexity.
>>>My most probable choice would be the 912S because it seems I can get
>>>great performance (the same or better than the Jabiru 3300) with
>>>relative ease of operation and mainenance, lighter weight, and
>>>comparable price to the Jabiru. I've even found a mechanic that is
>>>near (2 hours away) to my location. However, to the best of my
>>>research, it is still a more complicated engine and drive unit than
>>>the simple low reving Jabiru. It needs pump gas almost always, which
>>>may not be easy to come by during cross country flights.
>>>The Jabiru is the least expensive, most simple design, seems easier to
>>>maintain, and is direct drive. However, it's less proven, heavier and
>>>I can't find any repair facilities in the NY tristate area.
>>>Am I missing any other engine possibilities that could be even a better
>>>choice?
>>>
>>>
>>
>>
>>>
>>>
>>>
>>>
>>
>>
>>
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