Disassembly of connecting rod and piston group

Disassembling the connecting rod cap

Remove the bolts connecting rod cap, then remove the connecting rod cap and the lower connecting rod bearing liner.

Push piston and connecting rod assembly from the cylinder towards the surface of the cylinder head gasket.

Disassembly and assembly of the piston and connecting rod assembly (removal and installation of the piston pin)

With the help of special tools (09234-33001 and 09234-33002) perform the assembly and disassembly of the connecting rod and piston assembly (Fig. 2.268).

The piston pin is pressed into the upper head of the connecting rod and the piston slides thereon.

A set of special tools consists of a base with the stand and inserts, rails, adapters, stem-remover and a pusher rod-pusher to install. When removing or installing the piston pin piston is held on the basis of adaptation. The guide device facilitates positioning of the piston pin during removal and installation when the rod rests on the insert base.

To remove the piston pin lay at the base of the piston rod and place the inset base. Insert a push stick (for removal) through the top of the arc at the base of the piston pin and remove the finger from a press (Fig. 2.269).

When installing a new finger, you must install the proper insert the stand to support the rod.

Place the top of the head inside the piston rod. On one side of the piston, insert the corresponding guide through the piston and connecting rod, then gently lay siege at the hands of the guide, it is held to the piston. On the other side of the piston, insert piston pin and lay together piston and connecting rod on the base device so that the guide pin was below.

Insert a push stick (for installation) through the opening arc top of the base all the way into the adapter in the piston pin and a hydraulic press Start pin into the piston and connecting rod upper head. Continue pressing-in until the guide pin to fall below the base and the pusher-rod abuts against the top of the base arch.

Check piston and piston pin

Check each piston for scoring, scoring, wear and other defects. Replace the piston in the presence of defects.

Check each piston ring for kinks, damage or significant wear. Replace the defective ring. If necessary, replace the piston at the same time it should be replaced by the piston rings.

Check that the piston pin is included in the piston boss. Replace the piston and piston pin set in the presence of defects. At room temperature, the gudgeon pin should be easy, without jamming of the piston to enter the lug by hand.

Checking of piston rings

Measure the clearance between the piston ring and the piston groove (Fig. 2.271).

If the measured backlash exceeds maximum permissible value, install a new piston ring and re-measure the gap. If the measured gap again exceeds the limit, replace the piston and ring assemblies. If the measured gap is less than the limit, replace the piston rings only.

The clearance between the piston ring groove and the piston are below.

Nominal value:

compression ring ?��1 - 0,04-0,08 mm;

compression ring ?��2 - 0,03-0,07 mm;

Limit:

compression ring ?��1 - 0,1 mm;

compression ring ?��2 - 0.1 mm.

To measure the clearance in the lock of a piston ring set piston ring into the cylinder bore.

Position the ring at right angles to the generatrix of the cylinder wall, gently moving it down with the piston. Measure the end gap of the ring with a flat probe. If the measured backlash exceeds the limit, replace the piston ring.

Measure a backlash in the ring lock feeler gauge.

If the measured backlash exceeds the limit, replace the piston ring.

The values of the gap in the lock of a piston ring are shown below.

Nominal value:

compression ring ?��1 - 0,20-0,35 mm;

compression ring ?��2 - 0,37-0,52 mm;

scraper ring - 0.2-0.7 mm.

Limit:

compression ring ?��1 and ?��2 - 0,8 mm;

scraper ring - 1.0 mm.

When replacing the piston rings without bore cylinder oversize check clearance in the lock ring at a point located at the bottom of the cylinder (zone of least wear).

When installing the connecting rod cap, make sure the label number of the cylinder (made during disassembly) on the connecting rod and connecting rod cap are aligned. When installing a new rod, make sure that the locking grooves in the cover inserts a rod and a rod on the same side.

Replace the connecting rod in the presence of damage to the end face of the upper or lower heads. If there is a bending or twisting of the rod or the surface of the piston pin hole at the top head of a rod is much worn, replace the connecting rod.

Checking the connecting rod

When installing the connecting rod cap, make sure the label number of the cylinder (made during disassembly) on the connecting rod and connecting rod cap are aligned. When installing a new rod, make sure that the locking grooves in the cover inserts a rod and a rod on the same side.

Replace the connecting rod in the presence of damage to the end face of the upper or lower heads. If there is a bending or twisting of the rod or the surface of the piston pin hole at the top head of a rod is significantly worn, replace the connecting rod.

Assembly

Install the oil ring expander (Fig. 2.272).

Install the upper scraper scraper ring. To do this first set one end of the scraper between the expander and groove of the piston, then hold the end of a scraper, press your finger on the scraper to make it into the groove, as shown in Figure 2.273.

Install the lower scraper scraper ring according to the previous procedure (Fig. 2.274).

Apply the engine oil on the piston and a piston ring groove around the entire circumference.

With piston ring expander to install the compression ring ?��2.

Install the compression ring ?��1 (Fig. 2.275).

Place the lock ring as far as possible from each other. Ensure that the locking of a ring is not located on the axis of the piston pin axis or perpendicular to this direction (Fig. 2.276). Before installing the piston and connecting rod into cylinder with special tool compress piston rings.

Install the unit upper main bearing shells.

Set in the main bearing caps lower liners (Fig. 2.277).

Install the half-ring of the thrust bearing in the main bearing cap ?��3 oil groove to the outside (Fig. 2.278).

When installing the piston, make sure that the label "before" on the piston and the label "upstream" on a rod directed towards the front of the engine (for timing belt).

When installing rod cap cylinder number on the cover and the connecting rod must be positioned with one hand.

When installing a new rod, make sure that the latches on the connecting rod bushings and rod cover on the same side.

Tightening the connecting rod cap is held by angular.

1. Apply oil to the threads of nuts and the contact rod nuts and bolts.

2. Tighten bolts of covers of rods nominal torque and tighten to the specified angle.

Tightening torque of nuts of covers of rods 16-20 Nm + 90-94 ?�.

Check the lateral clearance between the underside of the connecting rod and crankshaft cheek (Fig. 2.279).

Backlash bottom head of a rod:

Nominal value - 0.10-0.25 mm;

Limit - 0.40 mm.