Piper COMANCHE PA-24-180 Service Manual page 504

PIPER COMANCHE SERVICE MANUAL
roller or blunt instrumet, roll or press the patch to the cemented area and roll or pess it down
a half-inch to an inch acros at a time so a not to trap air between patch and cell. Lay a 50
pound shot beg over patch which is protected by a piece of Holland Cloth to prevent sticking.
Weight should not be removed for 6 houn.
7. Seal coat edge of patch 1/2 inch with one coat of U.S. Rubber Co. 3230 or Minnesota
Mining Co. EC-678 cement and allow the cament to dry thoroughly.
b. Inside of Cll.
1. After the damaged area has been patched on the outside of the cell and the repair al-
lowed to stand a minimum of 6 hours, the cell is then ready to have the patch applied on the
inside of the cell.
2. Lightly and thoroughly buff a piece of cured U.S. Rubber Co. 5200/87 nylon sandwich
material large enough to cover damage at least 2 inches from cut in any direction. Wash buffing
dust off patch with Methyl Ethyl Ketone solution (U.S. Rubber Co. 3339).
3. Cement buffed side of patch with two coats of black rubber cement. U.S. Rubber Co.
3230 or Minnesota Mining Co. EC-678, and allow each coat to dry 10 to 15 minutes.
4. Buff cell are to be patched lightly and thoroughly with fine emery cloth and then wash
off buffing dust with Methyl Ethyl Ketone solution (U.S. Rubber Co. 3339).
5. Coat buffed area with two coats of black rubber cement, U.S. Rubber Co. 3230 or Minne-
sota Mining Co. EC678, and allow each coat to dry 10 to 15 minutes.
6. Freshen cemented area of patch and cemented area of cell with Methyl Ethyl Ketone
solution (U.S. Rubber Co. 3339).
7. While still tacky, apply edge of patch to edge of cemented area, centering patch over
cut in cell. With a roller or blunt instrument, roll or press the patch to the cemented area on the
cell Hold part of patch off the cemented area and roll or ress it down a half-inch to an inch at
a time so as not to trap air between patch and cell. Apply 50-pound shot bag to repaired area and
do not disturb for 6 hours.
8. Seal coat patch and 1/2 inch from edge of patch with two coats of U.S. Rubber Co.
3230 or Minnesota Mining Co. EC-678 cement. Allow the first coat to dry 15 minutes or more and
the second coat to dry 12 hours or more so that when the cell is in its folded or original poition
the patch area will not stick to other areas of the cell. Wipe patch and cemented area lightly with
number 10 oil.
c. Scuffed Fabric.
1. Buff area surrounding scuffed fabric.
2. Wash buffing dust from area with 3339 solution.
3. Apply two coats of U.S. Rubber Co. 3230 or Minnesota Mining Co. EC-678 cement to
the buffed area, allowing 10 minutes drying time between coats.
8-12. Fuel Selector Valves.
8-13. Removal Of Fuel Selector Valves, Removal of the fuel valve on all models of Comanche
aircraft are basically the same.
a. Drain fuel from the fuel cells.
b. Remove the fuel selector valve handle.
c. Remove the screws securing the fuel valve protector plate and remove plate. If plate is
wired with selector switches,bring the plate straight up, being careful not to damage the switches
FUEL SYSTEM
ISSUED: 8/18/72
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