Ford Sierra

1982-1993 of release

Repair and operation of the car

Ford Siyerra
+ 1.2. Identification of the car
+ 2. Maintenance
- 3. General data
   + 3.1. Cars with petrol engines
   - 3.2. Cars with diesel engines
      - 3.2.1. Changes in a car design from 1988 to 1993. Dm3 engine 2,3
         + Dm3 engine 1,8
         + Fuel system
         + The repair which is not demanding removal of the engine Removal and installation of the engine Dismantling of the engine Check of details Check of gaps of a bent shaft and rods Assembly of the engine Lubrication system Cooling system Coupling Mechanical MT 75 five-speed transmission Power shaft and back bridge System of steering Forward suspension bracket Brake system Electric equipment General data
+ 4. Engines
+ 5. Coupling
+ 6. Transmissions
+ 7. Driveshaft and back bridge
+ 8. Steering
+ 9. Suspension brackets
+ 10. Brake system
+ 11. Body
+ 12. Electric equipment

a773976c Check of gaps of a bent shaft and rods


Inserts of the first radical bearing (from the drive of system of gas distribution) have the bigger size, than inserts of other bearings, and both have an oil flute. In other bearings inserts from the block of cylinders have an oil flute, and from a cover have a smooth surface.

Check of radial gaps

The radial gap is measured in radical and conrod bearings of a bent shaft by means of special measuring cores of Plastigage from artificial material. The measuring core laid along a neck (radical or conrod) and clamped in the bearing is exposed to flattening. The radial gap in the bearing can be defined (on the basis of the corresponding scale on packing of measuring cores) depending on width of the deformed core.

Measurement conditions by means of measuring cores of Plastigage:

  – necks and inserts have to be dry and are carefully fat-free;
  – the bent shaft should not change the situation in process of installation and extraction of measuring cores;
  – the measuring core has to be laid in half of insert, at bigger distance from an oil opening in an insert or a neck of a shaft;
  – covers of bearings have to be established manually, and their bolts have to drag on the corresponding moment; it is impossible to strike blows to covers;
  – it is necessary to tighten only a cover of the bearing in which the radial gap is measured; it is impossible to measure gaps in all radical bearings at the same time.

1. To install inserts on radical bearings in the block of cylinders of the engine and to establish in them a bent shaft.
2. To lay a measuring core of Plastigage on the first radical neck.
3. To establish a cover of the radical bearing together with an insert and to tighten fastening bolts the corresponding moment.
4. To carefully uncover the bearing and to measure width of the deformed measuring core by means of the scale delivered together with measuring cores and on the basis of the table or the schedule to define a radial gap in the bearing.
5. To compare the measured value to the necessary size of a gap (see subsection If the measured gap exceeds admissible value, then it is necessary to use repair inserts.
6. In the similar way to measure a gap in other radical and conrod bearings.

Provrka of an axial gap

1. After installation of a bent shaft in the block of cylinders it is necessary to establish persistent half rings of a bent shaft (oil flutes have to be directed outside of the radical bearing), covers of bearings and to delay their fastening the corresponding moment.
2. To rest a measuring tip of the indicator of hour type against an end face of a bent shaft and to measure its axial gap.
3. To compare the measured values to necessary sizes (see subsection If the gap exceeds admissible value, then it is necessary to use repair persistent half rings according to bigger thickness.

Check of piston rings and gap of the piston in the cylinder

1. After removal of rings from pistons it is necessary to measure their gap in piston flutes, and after installation in cylinders in which they stood earlier, to measure width of the lock (gap) between their ends (see subsection
2. To measure diameters of cylinders and diameters of pistons (in the directing part, openings of a piston finger are lower) at right angle to an axis of a piston finger. The piston gap is equal in the cylinder to a difference of these two measurements.
3. By means of special adaptation to install rings on pistons so that inscriptions (or designations) were directed towards a piston bottom. Cuts of rings to arrange at an angle about 120 °.