> I have a Rotax 914 Turbo installed in a Europa XS, it currently has 65 Hrs
> logged from new, and runs on Mogas.
> Last weekend after 30 minutes duration I experienced two short coughs from
> the engine in quick
> succession. At this point I Selected the auxiliary fuel pump and changed
> fuel tanks to reserve.
> I returned back home having experienced no further problems. I considered
> the cough
> to be exaggerated due to the clutch mechanism of the prop.
> Once landed, after a visual check of the aircraft, I decided to carry out
> some circuits.
> After the first touch and go, I applied full power, started to climb and
at
> Approx 100 ft the engine
> coughed again, this time three times, I selected the Aux fuel pump
> and requested a precautionary tight circuit of the field and landed. This
> is the only occasion
> that I have experienced any coughs with this engine.
> Later, I drained and filtered the entire contents of the fuel tank which
was
> free from any
> contamination. 15 Hours ago the fuel filters had been replaced, and I
have
> now replaced them again.
> I also checked the fuel flow rate from both fuel pumps, which appeared to
be
> functioning correctly.
> On further closer inspection of the aircraft, I discovered that the Air
> filter had detached itself
> from the air inlet manifold and was lying in the base of the lower
cowling.
> Has anyone else experienced
> this problem? Do you think that this is the likely cause of the engine
> problems, running too lean?
> If so, what would you advise I do before considering flying it again?
>
> Eamonn Sheridan
A lack of air filter can result in the engine running to lean - i.e. too
much air going in, this causes several effects, one is to run too hot. Did
you check the temp. of the engine when it coughed? Also check the state of
the plugs and if it's run too hot for a long time, do a compression test in
case there are other problems (warped head, burnt valve...).
Cheers,
Mark.
p.s. I don't know anything about the Rotax, I'm just talking in general.
________________________________
Mark Jackson - +44 (0)7050 645590
europa-builder@ntlworld.com
http://harley.pcl.ox.ac.uk/~mark/Europa
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