And perhaps the below is common knowledge, if so
sorry, I personally had to find it out the hard way Perhaps the reason
is only because I am not and never have been much of a the mechanical type
of guy.
 For some un known reason, the Rotax 582 and ONLY this unmentionable
helicopter seem to not be comparable. My helicopter (the CH-7 Angel) along
with at least 135 more of it's brothers n sisters uses the SAME
engine with NO problems. To date, the only fatality that I know of
in the Angel was when a Italian pilot took off into the evening sun and a
set of wires.......
However, even though the CH-7 Angel uses the same power plant, the
manufacture of the helicopter (NOT the Rotax manufacture) recommends
adjusting the oil throttle differently than the Rotax manufacture
recommends.......
Now, I stress that the below Is NOT the way the
Rotax operators manual recommends adjusting the 582's oil throttle.
And the foto below is almost the way I have Miss Nina's throttle adjusted,
which is ALSO NOT the way the CH-7 Angel manufacture recommends......
You may have noticed how an Angel smokes when it is started from being
cold. My
little Miss Nina does..... The Rotex company recommends adjusting the oil
throttle so when the engine throttle is closed the oil throttle lever is
at the left most mark. The Angel's manufacture recommends the
throttle be aligned at the right most mark (hard to C
in this photo) when the throttle is closed......
Not liking how Nina's EGT were always close to the red line and almost
always touching the red in a decent, no matter how I jetted, I decided to
re adjust against what the engine manufacture
suggested and try what the air frame manufacture suggested.... Well after
doing so, my EGTs were lots better, but my plug checks were scary. Nina's
plugs were all gummy and agents All what I had been taught about reading
spark plugs and what you should be looking for...... But still the EGT
were great....
Then it dawned on me....... I decided to do a plug check with out a cool
down... I flew Miss Nina, landed quickly and Switched
off the engine WithOut a cool down period. Seems to reason the low
RPM of the cool down period of 2 min. would be giving me plug readings of
the cool down period, Not the true readings from flight...... Any way to
make a long story, I ended up compromising and not adding quite as much
oil as the helicopter mfr. suggested. I now have Nina set almost exactly
in-between the two marks according to plug readings I was looking for.
However, with the same setting after a cool down period, still look scary,
on the virge of fowling. But when visually inspecting the plugs with out
the 2 minute cool down, all 4 plugs looked good n the EGTs were always in
the green arch, even in a shallow decent w/power. |
