Attention:
- When working on the fuel tank or fuel lines, do not smoke or use open flames in the workplace.
- Be careful not to splash fuel when disconnecting the fuel connectors.
- Wear leak-resistant nitrile gloves and goggles with side protection when working.
- To prevent contaminants from entering the fuel system circuit, use plugs to plug the openings of the disconnected components.
- Measures must be taken to protect surfaces that may be exposed to escaping fuel to prevent corrosion or damage.
Due to the high operating pressure, the injection system of a diesel engine is extremely sensitive to various contaminants that can cause:
- damage or destruction of injection system components;
- increased wear of components;
- inadequate tightness of components.
All maintenance procedures must be carried out in conditions of perfect cleanliness. The work must be carried out in such a way that no particles (down to several microns) did not penetrate the system during disassembly.
Cleanliness principles must be followed for components from filters to fuel injectors.
Sources of pollution can be:
- metal or plastic filings;
- dye;
- foreign bodies (e.g. hair);
- atmospheric air;
- fibres, cardboard, bristle, paper, cloth, etc.
Attention: Do not clean the engine with a high pressure washer as there is a risk of damage to the connections. In addition, moisture can collect in connectors and cause electrical shorts.
Use only lint-free cloths for cleaning (part number 77 11 211 707). Do not use ordinary cloth or paper towels: these materials are a source of fluff or fibers that can contaminate the fuel injection system circuit.
Cleaning cloths can only be used once.
In case of disconnection of fuel system components, plugs must be used to prevent contaminants from entering the fuel circuit.
The end cap kit should only be used once. Used plugs must be disposed of: when used, plugs become dirty, and cleaning makes their further use impossible.
Note:
Numbers of plug kits for the K9K engine according to the spare parts catalog:
- DELPHI injection system: 77 01 206 804
- SIEMENS injection system: 77 01 476 857
Removed components that are to be reused should be stored in airtight plastic bags and tape to keep them free of contaminants. After use, such packages must be disposed of.
Two types of cleaners can be used to clean diesel injection system components:
- fuel injector cleaner (part number 77 11 224 188);
- brake cleaning spray (part number 77 11 226 128).
To use fuel injector cleaner, you will need a clean brush in good condition (bristles should not fall out of the brush), as well as a clean reservoir.
Note: Use only new cleaning agent to clean the injectors (previously used cleaning agent contains dirt).
Before working on the components of the diesel injection system, it is imperative to prepare:
- a set of new plugs corresponding to the engine model;
- a sufficient number of napkins made of lint-free cloth;
- cleaners for fuel line connectors;
- consumable items that must be replaced with new ones after each removal (To do this, you must first familiarize yourself with the repair procedure described in this manual).
Use goggles with side protection to prevent splashes of cleaning agent from splashing into your eyes.
Use latex work gloves to prevent prolonged contact of diesel fuel with the skin of the hands.
Note: When using leather work gloves, it is recommended to wear a pair of latex gloves over them.
Before working on the injection system, use plastic bags or a clean cloth to protect:
- drive belts;
- electrical components (starter, alternator, power steering pump, sensors and electrical connectors);
- flywheel surfaces.
Wash hands thoroughly before and during work.
If latex gloves are dirty or damaged, they must be replaced with new ones.
All removed components must be placed in airtight plastic bags immediately after removal. Use adhesive tape to seal the bags, even if the bag needs to be opened soon: atmospheric air can become a source of pollution.
After opening the fuel circuit, the use of brushes, cleaning agents, compressed air or ordinary cloths for cleaning is strictly prohibited: all this can cause contamination of the system.
When replacing components with new ones or reinstalling components from plastic bags, remove them from the packaging immediately before installation.
There are two ways to clean the components of the injection system before depressurization when performing any repair work. These procedures allow you to clean the outer surfaces of the components to prevent contaminants from entering the system: in the end, both procedures lead to the same result, so both methods are equally effective.
Cleaning with fuel injector cleaner
1. Clean surfaces around connections to be opened (see relevant section of this manual).
2. Take measures to protect areas where escaping fuel can get in.
3. Fill a suitable, clean container with fuel injector cleaner.
Caution: Use latex gloves when handling the cleaner.
4. Immerse a clean brush that does not have loose bristles into a container of cleaning agent.
Caution: Use goggles with side protection for the following procedure.
5. Thoroughly clean the connections with a brush dampened with cleaning agent.
6. Use compressed air to blow off surfaces that must be clean when performing repairs (tools, workbench and other work area surfaces, connections and surfaces around injection system components). Make sure that there are no bristles left from the brush, and that all surfaces are clean.
7. Wipe cleaned surfaces with a clean, lint-free cloth.
8. Open the system at the connection and install the appropriate plugs immediately.
Caution: Do not use compressed air when opening the fuel system circuit to prevent the ingress of contaminants. If necessary, only lint-free cleaning wipes may be used.
Cleaning with a brake cleaner spray
1. Clean surfaces around connections to be opened (see relevant section of this manual).
2. Take measures to protect areas that may be exposed to escaping fuel.
Caution: Use latex gloves when handling the cleaner.
Caution: Use goggles with side protection for the following procedure.
3. Spray a brake cleaner spray on the connections to be opened.
4. Thoroughly clean the connections with a clean, lint-free cloth.
5 Use compressed air to blow off surfaces that must be clean when carrying out repairs (tools, workbench and other work area surfaces, connections and surfaces around injection system components). Make sure that there are no bristles left from the brush, and that all surfaces are clean.
6. Open the system at the connection and install the appropriate plugs immediately.
Caution: Do not use compressed air when opening the fuel system circuit to prevent the ingress of contaminants. If it is needed. Only lint-free cleaning wipes may be used.