Raytheon Beech Baron E55 - Page 455

Ray~hean
Aircraft
Company
BARON
55
AND
58
SHOP
MANUAL
COMBUSTION
CHAMBER
AND
RADIA
TOR
INSPECTION
I
cnuTlow
I
CAUTION
If
any
soft
spots
are
located in the
combustion
chamber
and
radiator
assembly,
there
is
a
malfunction
in
the heater
system
and
a new
heater
should
not
be
installed
until the
trouble has
been
corrected.
a.
Slight
scaling
and
discoloration
of
the combustion
chamber
and
radiator
assembly
is
a
normal
condition
on
heaters that
have been in
use.
The
scale will be
mottled
and
a
blue
powder
can
be rubbed off of
the
scaled
areas.
This
does
not constitute
ground
for
rejecting
the
heater since
considerable life
can
still
be
expected
if
there
are
no
soft
spots
in the
metal
where it has
been
subjected
to
severe
overheating.
b.
Severe
overheating
will
result
in
general
weakening
of
the
metal that
results in
soft
and
spongy
spots.
These
are
usually
found
directly opposite
the
crossover
passages.
They
can
be
detected
by
tapping
lightly
with
a
ball
peen
hammer.
This
will
give
a
slightly
soft
or
spongy
response
in
contrast
to
a
solid
feel
when
tapping
on
live
metal.
These
soft
spots
will
usually
have
a
dull
gray appearance
indicating
considerable
surface
oxidation.
The
presence
of
soft
spots
is
reason
for
rejecting
the
combustion
chamber
and
radiator
assembly.
REMOVING
THE
CABIN HEATER
NOTE
The heater
can
be
removed without
removing
the
radio
shelf,
but
can
be
accomplished
more
readily
if the
shelf
is
loose
or
removed.
a.
Remove the
nose cone
attaching
screws
and
the
nose
cone.
b. Disconnect
the
iris
valve
control,
blower
wiring
and
the
igniter
leads.
c.
Remove the
bolts
attaching
the
iris
valve
to
the heater
and
forward
support.
d.
Remove
the
screws
and
remove
the
forward
support.
e.
Remove
the
screws
holding
the
exhaust
pipe
and
remove
the
pipe.
f. Remove the
combustion air flex
duct
from
the
heater.
g.
Disconnect
the fuel
lines
from
the
heater
and
cap
the
openings.
h. Disconnect
and
remove
the
two heater
drain
lines.
i. Disconnect
and
remove
the hot air duct from
the heater.
j.
Remove the
aft
clamp
from
around the heater.
k.
Remove the
screws
from
the
upper
and
lower
plates
on
the
No.
1
bulkhead
and
remove
the
plates.
NOTE
The
cabin heater
blower,
heater
ignition
unit and
the heater fuel
discharge
nozzle
are
an
integral
part
of
the
heater
and
are
removed
with
the
heater.
E20
SECTION
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