Piper SARATOGA PA-32-301 Maintenance Manual page 302

PIPER AIRCRAFT
PA-32-301/301T
MAINTENANCE MANUAL
DEFECT REPAIRS OF FUEL CELL.
I. Blisters: Remove loose material by trimming. Apply an outside and inside repair patch.
2. Holes. Punctures. Cuts. Tears and Deep Abraded Areas: Trim away any ragged material and apply
an outside and inside repair patch.
3. Loose Seams: Buff loose edges and contact surfaces with emery cloth. Wash three times with
Methylethylketone. Apply 80C27 mixed cement in two coats as with a repair patch. Clamp and cure. Either
method may be used. (See repair patch.) Loose seams may be trimmed if a minimum lap remains.
4. Loose Fitting Flange - Inside: Buff the edge of the flange and the contact surface under the flange.
Apply 80C27 mixed repair cement, cellophane, padded plates and clamp. Follow procedure as outlined for
repair patch.
5. Looseness Against Metal: Prepare metal as per metal fitting - sealing surfaces. Apply 80C27 mixed
cement and cure.
TESTING FUEL CELLS.
Either of the following procedures may be used to detect leaks in the bladder cells:
1. Soap Suds Test:
A. Attach test plates to all fittings.
B. Inflate the cell with air to a pressure of 1/4 psi MAXIMUM.
C. Apply a soap and water solution to all repaired areas suspected of leakage. Bubbles will appear
at any point where leakage occurs.
D. After testing. remove all plates and wipe soap residue from the exterior of the cell.
2. Chemical Test:
A. Attach test plates to all fitting openings except one.
B. Make up a Phenolphthalein solution as follows: Add 40 grams Phenolphthalein crystals in 1 2
gallon of Ethyl Alcohol. mix: then add 1/2 gallon of water.
C. Pour ammonia on an absorbent cloth in the ratio of 3 ml per cubic foot of cell capacity. Place a
saturated cloth inside the cell and install the remaining test plate.
D. Inflate the cell with air to a pressure of 1/4 psi maximum. cap and maintain pressure for fifteen
minutes.
E. Soak a large white cloth in the Phenolphthalein solution. wring it out thoroughly. and spread it
smoothly on the outer surface of the cell. Press the cloth down to insure detection of minute leaks.
F. Check the cloth for red spots which will indicate a leak. Mark any leaks found and move the
cloth to a new location. Repeat this procedure until the entire exterior surface of the cell has been covered. If
red spots appear on the cloth. they may be removed by resoaking the cloth in the solution.
G. The solution and test cloth are satisfactory only as long as they remain clean. Indicator solution
that is not in immediate use should be stored in a closed rust proof container to prevent evaporation and
deterioration.
After the test, remove all plates and test equipment. Allow the cell to air out.
In conducting either test outlined above, the cell need not be confined by a cage or jig. providing the 1 4
psi pressure is not exceeded.
-NOTE -
The chemical test is the more sensitive and preferred test.
28-12-16
Page 28-14
2B9
Revised: August 11. 1983
2B9