Fuel Cell Tie Detail Diagrams; Testing Fuel Cells ............................................................................................................ 2L12 - Piper Navajo Chieftain PA-31-350 Service Manual

STEP 1
STEP 2 STEP 3 STEP4
STEP 5 STEP 6 STEP 7
Figure 9-13 Fuel Cell Tie Detail
9-65. TESTING FUEL CELLS. Either of the following test procedures may be used to detect leaks in the
bladder cells.
a. Soap Suds Test.
1. Attach test plates to all fittings.
2. Inflate the cell with air to a pressure of 1/4 psi MAXIMUM.
3. Apply a soap and water solution to all repaired areas and any areas suspected of leakage.
Bubbles will appear at any point where leakage occurs.
4. After test, remove all plates and wipe soap residue from the exterior of the cell.
b. Chemical Test.
1. Attach test plates to all fitting openings except one.
2. 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.
3. Pour ammonia on an absorbent cloth in the ratio of 3ml. per cubic foot of cell capacity. Place
the saturated cloth inside the cell and install remaining test plate.
4. Inflate the cell with air to a pressure of 1/4 psi maximum, cap and maintain pressure for fifteen
minutes.
5. 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.
Revised: 3/31/94
FUEL SYSTEM
NAVAJO CHIEFTAIN SERVICE MANUAL
2L12