Dismantling

Dismantling

Observe scrupulous cleanliness when dismantling components, particularly when brake, fuel or hydraulic system parts are being worked on.

CAUTION: A particle of dirt or a cloth fragment could cause a serious malfunction if trapped in these systems.

• Blow out all tapped holes, crevices, oilways and fluid passages with an air line. Ensure that any O-rings used for sealing are correctly replaced or renewed, if disturbed during the process.
• Use marking ink to identify mating parts and ensure correct reassembly. Do not use a centre punch or scriber to mark parts, they could initiate cracks or distortion in marked components.
• Wire together mating parts where necessary to prevent accidental interchange (e.g. roller bearing components).
• Wire labels on to all parts which are to be renewed, and to parts requiring further inspection before being passed for reassembly; place these parts in separate containers from those containing parts for rebuild.
• Do not discard a part due for renewal until after comparing it with a new part, to ensure that its correct replacement has been obtained.

Cleaning components

Always use the recommended cleaning agent or equivalent.

WARNING: Ensure that adequate ventilation is provided when volatile degreasing agents are being used.

CAUTION: Do not use degreasing equipment for components containing items which could be damaged by the use of this process.

General Inspection

• Never inspect a component for wear or dimensional check unless it is absolutely clean; a slight smear of grease can conceal an incipient failure.
• When a component is to be checked dimensionally against recommended values, use the appropriate measuring equipment (surface plates, micrometers, dial guages etc.). Ensure the measuring equipment is calibrated and in good serviceable condition.
• Reject a component if its dimensions are outside the specified tolerances, or if it appears to be damaged. A part may be refitted if its critcal dimension is exactly to its tolerance limit and it appers to be in satisfactory condition.
• Use ’Plastigauge’ 12 Type PG-1 for checking bearing surface clearances.