General fitting instructions

GENERAL FITTING INSTRUCTIONS

Component removal

Whenever possible, clean components and surrounding area before removal.

• Blank off openings exposed by component removal.
• Immediately seal fuel, oil or hydraulic lines when apertures are exposed; use plastic caps or plugs to prevent loss of fluid and ingress of dirt.
• Close the open ends of oilways exposed by component removal with tapered hardwood plugs or conspicuous plastic plugs.
• Immediately a component is removed, place it in a suitable container; use a separate container for each component and its associated parts.
• Clean bench and provide marking materials, labels and containers before dismantling a component.

Dismantling

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

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

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

Whenever possible clean components and the area surrounding them before removal. Always observe scrupulous cleanliness when cleaning dismantled components.

General inspection

All components should be inspected for wear or damage before being reassembled.

• 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 gauges 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 critical dimension is exactly to its tolerance limit and it appears to be in satisfactory condition. Use ’Plastigauge’ 12 Type PG-1 for checking bearing surface clearances.