Ford Sierra

1982-1993 of release

Repair and operation of the car

3.2.1.2.4. Krivoshipno-shatunny mechanism

GENERAL INFORMATION

Krivoshipno-shatunny mechanism

1 – bent shaft,

2 – intermediate shaft,

3 – inserts of radical bearings of a bent shaft,

4 – persistent half rings of a bent shaft,

5 – pulley,

6 – covers of radical bearings,

7 – rod,

8 – rod cover,

9 – inserts of conrod bearings,

10 – piston,

11 – piston rings,

12 – lock spring ring,

13 – piston finger,

14 – rod head plug

Bent shaft

The bent shaft is made of cast iron together with eight counterbalances and leans on five radical bearings.

Diameter of radical necks:
– nominal	53,970 – 53,990 mm
– repair-0,25	53,720 – 53,740 mm
– repair-0,50	53,470 – 53,490 mm
Diameter of conrod necks:
– nominal	48,970 – 48,990 mm
– repair-0,25	48,720 – 48,740 mm
– repair-0,50	48,470 – 48,490 mm
Width of the average radical bearing:
– nominal	31,070 – 31,130 mm
– repair	32,070 – 32,130 mm
Radial gap of radical bearings of a bent shaft	0,015 – 0,062 mm
Axial gap of a bent shaft	0,093 – 0,306 mm
The maximum moment of friction in radical bearings of a bent shaft (without the established knots the piston rod)	10 Nanometer

Inserts of radical bearings

Inserts are thin-walled. The manufacturer does not give the sizes of inserts.
As spare details inserts nominal and repair are delivered: reduced by 0,25 mm and 0,50 mm.

Rods

Rods with four distances between axes of openings of a head and the basis for providing one extent of compression in all cylinders of the engine are made. The designations "A", "B", "C" and "D" put on a side surface of covers of rods define selective group of distance between axes of openings of a head and the basis.

Method of installation of a rod concerning the block of cylinders: the letter "F" put on a side surface of a rod has to be from the drive of system of gas distribution.

Diameter of an opening of a nest of an insert of the conrod bearing: 52,000–52,020 mm.

Diameter of an opening in the rod head plug: 26,012–26,020 mm.

Distance between axes of openings of a head and the basis of a rod:

– group A: 129,880–129,940 mm;
– group B: 129,941–130,000 mm;
– group C: 130,011–130,060 mm;
– group D: 130,061–130,120 mm.

Inserts of conrod bearings

Thin-walled inserts. The manufacturer does not give the sizes of inserts. As spare details inserts nominal and repair are delivered: reduced by 0,25 mm and 0,50 mm.

Pistons

Pistons from light alloy with the filled-in steel insert are used.

Diameters of pistons (measured at right angle to an axis of a piston finger):
– nominal:
• group A	82,460 – 82,475 mm
• group B	82,475 – 82,490 mm
• group C	82,620 – 82,635 mm
• group D	82,635 – 82,650 mm
– repair:
• group E (+0,5 mm)	82,961 – 82,979 mm
• group F (+1,0 mm)	83,461 – 83,479 mm
Piston gap in the cylinder:
– groups A and D	0,025 – 0,055 mm
– groups E and F	0,021 – 0,054 mm
Vystupaniye in piston bottom VMT over the top plane of the block of cylinders	0,50 – 0,84 mm

Piston fingers

The finger rotates in the piston and the plug of a head of a rod (a so-called floating finger) and is recorded from longitudinal movement by two spring lock rings.

Installation of lock rings in a piston flute: section up.

Outer diameter of a finger: 25,996–26,000 mm.

Piston rings

Each piston has three rings: two sealing and one oil scraper.

Installation method: the inscription "Top" (top) is directed towards a piston bottom.

Width of the lock (section) of the ring located in the cylinder:

– top ring (sealing): 0,35–0,50 mm;
– average ring (sealing): 0,35–0,50 mm;
– lower ring (oil scraper): 0,25–0,45 mm.

Gap in a piston flute:

– top ring (sealing): 0,090–0,122 mm;
– average ring (sealing): 0,050–0,082 mm;
– lower ring (oil scraper): 0,030–0,065 mm.

Flywheel

Radial beats: 0,13 mm.
Number of teeths of a wreath: 135.