Diesel Injection; Diesel Injection: Precautions For The Repair - Renault Laguna III Manual

Diesel injection: Precautions for the repair

K9K or M9R or V9X
I - RISKS RELATING TO CONTAMINATION
The high-pressure direct injection system is highly sen-
sitive to contamination. The risks caused by contami-
nation are:
- damage to or destruction of the high pressure injec-
tion system,
- a component seizing,
- a component not being properly sealed.
All After-Sales operations must be performed under
very clean conditions. Having carried out an operation
in good conditions means that no impurities (particles a
few microns in size) have penetrated the system during
dismantling.
The cleanliness principle must be applied from the filter
to the injectors.
What are the sources of contamination?
- metal or plastic swarf,
- paint,
- fibres:
• cardboard,
• brushes,
• paper,
• clothing,
• cloth,
- foreign bodies such as hair,
- ambient air,
- etc.
WARNING
Do not clean the engine with a high pressure
cleaner to prevent damaging the connections.
1 - Cleaning cloths
Use lint-free cleaning cloths (see Vehicle: Parts and
consumables for the repair) (04B, Consumables -
Products).
It is prohibited to use cloths or ordinary paper towels:
these produce lint and lose fibres, which then contami-
nate the fuel circuit.
Each cloth must only be used once.

DIESEL INJECTION

13B-1
2 - Blanking plugs
The blanking plugs are used to cap the fuel circuit once
it is opened and to therefore prevent contaminants
from entering.
A set of blanking plugs should be used once only and
used plugs must be discarded after use: once used,
the plugs are soiled and cleaning them is not sufficient
to make them reusable.
Unused plugs must also be discarded and must not be
used when carrying out work on an injection system.
Part number for set of blanking plugs: (see Vehicle:
Parts and consumables for the repair) (04B, Con-
sumables - Products).
Note:
There is no specific set of blanking plugs for S9U
and S9W engines. In order to comply with the
cleanliness recommendations, use plugs that are
compatible with the blanking plug sets for F9Q,
G9U, G9T or ZD3 engines.
3 - Protective bags
Use hermetically-resealable plastic bags, using adhe-
sive tape, for example, to store components which will
be refitted and reused. Stored parts will therefore be
less subject to the risk of contamination.
These are single-use bags: after use they must be dis-
carded.
4 - Cleaning products
Two cleaning products can be used:
- an injector cleaner (see Vehicle: Parts and consum-
ables for the repair) (04B, Consumables - Products),
- an aerosol spray brake cleaner (see Vehicle: Parts
and consumables for the repair) (04B, Consum-
ables - Products).
To use the injector cleaner, be sure to have a clean
brush in good condition (the brush must not lose any
bristles) as well as a clean container which has no im-
purities in it.
Note:
Use a new injector cleaner each time work is car-
ried out (a used cleaning agent will contain impuri-
ties).
13B