Wrinkled Deicers; Deicer Electrical Check - Piper PA-44-180 SEMINOLE Maintenance Manual

WRINKLED DEICERS. ( Refer to Figure 30-12)
If edge of deicer is found wrinkled or loose, try recementing. Use MEK or Toluol to loosen the bond for an
additional 1/4 inch beyond the loose or wrinkled area. Apply one coat of 1300L cement to the deicer and
propeller bonding surfaces and allow to air dry for one hour. Then apply a second coat of 1300L cement to both
the deicer and bonding surface. Allow to dry. Retackify with MEK or Acetone and press with fingers to work
out wrinkles or to secure loose edges. If material has stretched and will not cement flat, replace the deicer.
ELECTRICAL CHECK.
1. Check the electrical resistance of element within the deicer. (Refer to Chart 3007.)
2. Check for intermittent open circuits by tensioning the deicer wire harness slightly while measuring the
resistance. Also, press lightly on the deicer surface in the area adjacent to the harness. Resistance must not
vary.
3. Identification of the circuits within the element may be confirmed by referring to the resistance values and
schematic diagram. Proper identification is necessary in order to make the system cycle properly and to
obtain the correct amperage values during system operation. Minimum and maximum ohms between
common ground and either of the other terminals is 1.04 to 1.12.
These resistances apply only to deicers that are not connected to terminal studs
Material
Filler 3M EC1031 and EC801
Sealer BFG 82-076-1 &-2
or
Lowe Brothers V66V27, F63B8,
& R7K69
Resistance Check
.
1 Blade each Element
2 Blades in Parallel
3 Blades in Parallel
PIPER AIRCRAFT
PA - 4 4 - 1 8 0 / 1 8 0 T
AIRPLANE MAINTENANCE MANUAL
— Note —
CHART 3006. MIXING OF MATERIALS
Manufacturing & No.
CHART 3007. ELECTRICAL RESISTANCE
Mixing Proportions
Twelve parts EC1031 with one hundred
parts EC801
Twelve parts -1 with one part -2
One part V66V27 with seven parts
F63B8 (and up to two and two-thirds
parts R7K69 thinner as needed)
Max.
1.12
0.56
0.38
2E23
Min.
1.04
0.52
0.35
3 0 - 6 8 - 1 0
Page 30-43
Revised: May 15, 1989