65637bd9



3.1.2.11.2. Installation and check of gaps in conrod bearings


Prevention

The description concerns only conrod bearings of the standard size. Repair connecting rods are not subdivided into dimensional groups.


New conrod bearings are selected by the codes of dimensional group put on the crankshaft.

Codes of dimensional groups are applied on the 1st or on the 4th crankshaft cheeks.

To pick up inserts of conrod bearings it is necessary to learn dimensional group of a conrod neck of the crankshaft for this cylinder, and then to determine the necessary insert by the enclosed table, being guided on color marking which in the form of a point is applied on a side surface of an insert.

Code on the crankshaft
Color marking of dimensional group of an insert
0
white (or is absent)
1
brown
2
green

Check of a gap in conrod bearings

PERFORMANCE ORDER
1. Clear an external surface of connecting rods and the surface of boring under inserts in rods and in covers of rods.
2. Insert on inserts and be convinced that ledges on inserts of the bearing came into selections in a rod (shooter) and in a rod cover.
3. At installation of inserts it is forbidden to touch a working surface. Make sure that the lubricant opening in the top connecting rod was precisely combined with an opening in a rod.
4. If check of a gap is carried out with old inserts, then insert these inserts on former places.
5. The gap in conrod bearings can be checked in two ways.
6. When determining a gap collect by the first way covers with rods and conrod bearings, having tracked correctness of mutual orientation of these details.
7. Tighten nuts of covers with the set moment and measure the internal diameter of each collected couple of inserts. The gap is defined as a difference of internal diameter of assembled conrod bearings and diameter of a conrod neck.
8. The second way (more exact) consists in application of a plastic calibration wire.
9. Install conrod bearings, it is correct them having oriented. On each conrod neck of the crankshaft put on a piece of a calibration wire.
10. Clear surfaces of connecting rods and establish rods on the corresponding necks of the crankshaft. Establish covers of conrod bearings, having oriented them on the available tags, or the put tags when dismantling.
11. Tighten nuts of covers. When tightening change of provision of a wire is not allowed, the crankshaft provorachivaniye is also not allowed.
12. Uncover rods, without allowing at the same time turn of the crankshaft or shift of a calibration wire. Compare width of the flattened wire to a scale on packing and define a gap in radical bearings.
13. If the gap differs from standard, then the wrong selection of connecting rods can be the cause (or their increased wear if the inserts which were in operation were checked).
14. Before coming to a conclusion about need of replacement of inserts be convinced that between surfaces of covers or rods and an insert at measurement there were no dirt or oil.
15. If width of the flattened wire from one edge is more, then it indicates conicity of a conrod neck.
16. If the gap differs from norm at measurements with old inserts, then repeat measurements with new inserts.
17. If and with new inserts the gap exceeds norm, then it is necessary to address for consultation in service of car service. Regrinding of conrod necks of the crankshaft and replacement of inserts repair can be necessary.
18. If necessary get inserts of the corresponding dimensional group and repeat the procedure of measurement of a gap in conrod bearings.
19. Upon termination of carefully remove the wire remains.

Installation of conrod and piston group

The further description is kept in that assumption that the crankshaft is already installed.

PERFORMANCE ORDER
1. Be convinced of correctness of installation of conrod bearings.
2. If new bearings are installed, then wash out them in kerosene.
3. Dry wipe rods and bearings.
4. Grease cylinders, pistons and rings, then lay out pistons assembled with rods in that sequence in which these details will be established on the engine.
5. Begin assembly with the 1st cylinder. Be convinced of the correct arrangement of joints of piston rings (cm. subsection 3.1.2.13) also squeeze rings special adaptation.
6. Insert the piston assembled with a rod into the first cylinder. Orient the piston so that the tag on the piston bottom (in the form of an arrow or line) was turned towards a forward cover. Slightly knock on the piston with the handle of the hammer or wooden whetstone that the piston came into the cylinder and the bottom of the piston it was made even to the demountable plane of the block of cylinders.
7. Make sure that connecting rods are established correctly and plentifully grease inserts and a conrod neck of the crankshaft.
8. Carefully, not to damage the surface of the cylinder, attract a rod to a crankshaft neck.
9. Put on a rod cover with an insert and tighten nuts by hand. Keep in mind that the planes on a rod and on a rod cover on whom tags are applied have to be combined (it means that adjusting ledges of conrod bearings are located opposite to each other).
10. Tighten nuts of conrod covers with the moment of the 1st stage of an inhaling by means of a dynamometer key and a face head. Then tighten nuts on a corner of the 2nd stage of an inhaling, or tighten with the moment of the 2nd stage.
11. Check freedom of rotation of the crankshaft. If new details are established, then the noticeable constant resistance to rotation of the crankshaft has to be felt, however the crankshaft has to be turned smoothly, without jammings.
12. Similarly install other pistons and rods.
13. Establish a head of cylinders, chains of cam-shafts and the oil pallet.