General Fitting Instructions

GENERAL INFORMATION

03-6

General Fitting Instructions

Component removal
Whenever possible, clean components and 
surrounding area before removal. 

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Blank off openings exposed by component 
removal. 

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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. 

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Close the open ends of oilways exposed by 
component removal with tapered hardwood 
plugs or conspicuous plastic plugs. 

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Immediately a component is removed, place it in 
a suitable container; use a separate container 
for each component and its associated parts. 

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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.

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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.

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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.

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Wire together mating parts where necessary to 
prevent accidental interchange (e.g. roller 
bearing components).

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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.

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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.

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

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Never inspect a component for wear or 
dimensional check unless it is absolutely clean; 
a slight smear of grease can conceal an 
incipient failure.

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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. 

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Reject a component if its dimensions are 
outside the specified tolerances, or if it appears 
to be damaged.

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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.