Audi 100/A6

1990-1997 of release

Repair and car operation

Audi 100/A6
+ 1. Maintenance instruction
+ 2. Maintenance
+ 3. Engines
+ 3.2. Diesel engines
- 3.3. Removal and partition of engines
   + 3.3.2. Technical characteristics
   3.3.3. Repair work, possible without engine dismantle
   + 3.3.4. Major maintenance
   3.3.5. Removal and engine installation
   3.3.6. Engine partition
   + 3.3.7. Head of cylinders
   3.3.8. Pistons and rods
   + 3.3.9. Cranked shaft
   3.3.10. Intermediate shaft
   3.3.11. Block of cylinders
   3.3.12. Radical bearings and bearings of rods
   3.3.13. Piston rings
   3.3.14. The first start of the engine after a partition
+ 4. Cooling system
+ 5. Heating and ventilation
+ 6. Fuel system
+ 7. Exhaust system
+ 8. Systems of start, ignition
+ 9. Transmission
+ 10. Brake system
+ 11. Suspension brackets, steering
+ 12. Body
+ 13. Electric equipment
+ 14. Good advice


3.3.8. Pistons and rods


Piston and rod

1. Piston rings
2. Piston
3. Piston finger
4. Lock ring
5. Rod
6. Rod loose leaf
7. Block of cylinders
8. Rod cover
9. Adjusting pin
10. Oil jet
11. Screw of an oil jet
12. Bolts of a cover of a rod
And – identification labels on a rod and a rod cover
In – oriyentatsionny labels


Piston and rod

1. Remove a head of cylinders, a flywheel, the oil pallet, the oil pump and a maslozaborny branch pipe.
2. Remove a ledge in the top part of the cylinder, formed as a result of wear.
3. If rods and covers of rods are not marked, mark them.
4. Establish N1 and N4 pistons in the bottom dead point.
5. Turn off fixing nuts, and uncover the first rod and the bearing loose leaf, mark loose leaves.
6. Put on pieces of a rubber tube rod bolts not to injure a neck of a cranked shaft and a cylinder wall.

7. Remove the loose leaf of the bearing and get a rod from above the block of cylinders.
8. Remove other rods and pistons similarly.
9. Whenever possible unscrew screws and remove jets of pistons.


Piston (AAT) head

1. A small screw-driver remove lock rings of a piston finger and remove a finger. Examine a finger on existence of wear and damages, at detection of damages address to experts.
2. Remove piston rings. Clear a piston head of deposits and clean flutes for piston rings. After removal of all deposits. Clear pistons and rods solvent and dry up them.
3. Carefully examine all pistons on existence of cracks on a skirt of the piston and round a shatunny finger. Examine pistons on existence of scratches, задиров, the scorched areas or corrosion.
4. Examine rods on existence of cracks and other damages. For more detailed checking of pistons and rods address to experts
5. Measure diameters of all four pistons.
6. Measure a lateral gap of piston rings.
7. At carrying out assembly of the piston and a rod, pay attention that the arrow on a head of the piston should indicate towards a gas-distributing belt. Labels on a rod and on a cover of a rod should be directed in a turbonagnetatel the party.

Check of a lubricant gap of shatunny bearings

For measurement of a lubricant gap it is possible to use an internal micrometer or other special device, but the most exact and easy method it – to use a special plastic measuring instrument.

Temporarily establish the piston in the cylinder, tighten bolts of covers of rods, and check a lubricant gap of the shatunny bearing similar to check of a lubricant gap of radical bearings.

If size of a gap do not correspond demanded, possibly, loose leaves of the wrong size are established.

Final installation of pistons and rods

Arrangement of pistons and the coding in diesel engines

1. Remove all traces of plastic. Check, that the surface of loose leaves was absolutely pure, and grease them with engine oil.
2. Clean the top loose leaf of the bearing of a rod and establish it on a rod. Lubricant openings of a rod and the loose leaf should be combined.
3. Clean the second loose leaf and establish it in a rod cover.
4. Grease pistons and rings and compress piston rings by means of the compressor of piston rings.
5. Turn a cranked shaft so that the shatunny bearing of the first cylinder was in the family way the bottom dead point, and grease cylinder walls.
6. Check, that the mark from above the piston was turned forward.

7. Press on the piston and establish it in the cylinder.
8. Installation of other rods is carried out similarly.

9. Establish a rod on a neck of a shaft and establish a rod cover.
And – a pin (only a diesel engine)
In – an adjusting opening (only a diesel engine)
10. In diesel 4th cylinder engines 1Z and AHU and 5 of cylinder ABP, AAT, AEL pistons have a special form for the best combustion of a mix and should be correctly established (see fig. An arrangement of pistons and the coding in diesel engines).
11. Tighten bolts till the demanded moment of an inhaling.

12. Hold on bolts on a demanded corner.

13. After installation of all rods turn a cranked shaft several times and check ease of a course.


13. For exact selection of thickness of laying measure ledges of pistons by means of the special tool.