TM 9-2320-366-34-4
(2) Dry Magnetic Particle Method
NOTE
Magnetic yoke, magnetic particle powders, and cleaner/remover fluid shall be in accordance with
overhaul contract requirements.
(a) Thoroughly clean surface to be inspected.
(b) Apply cleaner/remover fluid to the cylinder head to remove any contaminants from surface to be checked.
(c) Place magnetic yoke on surface to be inspected at a right angle to the area to be checked.
(d) Apply magnetic powder on surface to be inspected when yoke is energized (turned on).
NOTE
If there is a crack in the surface between the yoke arms, the magnetic powder will go into the crack.
The crack will appear as a straight line of magnetic particles.
(e) Check surface being inspected for signs of cracks.
(3) Dye Penetrant Method (Liquid Non-Fluorescent).
NOTE
•
Cleaner/remover fluid, dye penetrant, and developer shall be in accordance with overhaul contract
requirements.
•
This method will not always find shallow cracks with a depth of up to 0.002 in. (0.005 cm).
(a) Thoroughly clean and dry surface to be inspected.
(b) Spray cleaner/remover on cylinder head to remove any contaminants from surface to be checked.
(c) Apply dye penetrant chemical on surface. Allow the dye penetrant approximately three to five minutes to enter
any cracks.
(d) Wipe penetrant from surface, using clean paper towel.
(e) Spray a light coat of developer solution onto surface to be inspected. A crack will appear as a colored line in
developer.
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