Crankshaft Magnetic Crack Inspection (1-07) Section 1 - Cylinder Block - Group 01 M11 Page 1-32 A minimum of three coil shots are required for each 18 inch length to correctly magnetize the crankshaft. Flow the magnetic bath solution over the crankshaft in one third sections. Apply three coil shots after each wetting with the coil placed at quarter-length points along the crankshaft. NOTE: Turn off the flow of bath solution before the third coil shot is completed to prevent washing the metal particles from the crankshaft. Inspect each 18 inch section after the third coil shot is completed. Magnetic Inspection - Limits of Acceptance Visually inspect for open indications.
An open indication is a crack open to the surface that can be seen without using optical enhancement. An open indication can sometimes be felt with a fingernail. Do not mistake forging trim lines for crack indications. If open indications are seen in the hardened fillet area or the critical areas shown (A), refer to the Alternative Repair Manual, Bulletin No. 3810310.. Open indications longer than 6 mm [1/4 inch] long are not acceptable. No open indications are permissible in any fillets or the critical areas.