:: ENGINE PROBLEM ::

Cylinder heads are crack tested using a few different methods. Two common methods are magnetic crack testing for cast iron and dye check for alloy heads. The magnetic cracktest uses a magnetic particle fluid and magnets. The particle fluid is drawn into the crack and is highlighted under ultra violet light. An older magnetic dry powder test uses the same principal of the magnetic powder being drawn into the cracks between the magnets. This powder line is visible under normal light. The dye check method for alloy heads involves the use of a pre cleaner, a dye and a developer. The dye penetrates the crack and when the excess is hosed off and the developer is applied, the crack is visible as a highlighted line.
All heads have to be fully dismantled and cleaned before any successful crack test can be done.