We remove the engine crankshaft during a major overhaul

The crankshaft rotates in main bearings with thin-walled steel liners with an anti-friction layer.

It is fixed from axial movements by two half rings installed in the grooves of the bed of the middle main bearing.

Removing the crankshaft

Conventionally, the engine is installed on the stand and the connecting rod and piston group is dismantled from it

Engine block and crankshaft: 1 - crankshaft main bearing lower shell; 2 - crankshaft; 3 - the top loose leaf of the radical bearing; 4 - front thrust semi-ring of the crankshaft; 5 - cylinder block; 6 - rear thrust half ring of the crankshaft; 7 - cover of the main bearing of the crankshaft; 8 - crankshaft main bearing cap bolt

We unscrew the bolts securing the connecting rod caps and disconnect the connecting rod heads from the connecting rod journals of the crankshaft, described in the article "Repair of the connecting rod and piston group of the Hyundai Solaris engine"

Remove the flywheel

We unscrew the bolts of the crankshaft main bearing caps in the reverse order of tightening during installation

How to replace crankshaft G4FA Hyundai Solaris

Remove the crankshaft and crankshaft thrust washers

Remove the liners from the covers and beds of the main bearings. We examine the liners.

If on the working surface of the liners there are risks, scuffs, delamination of the antifriction layer, we replace the liners with new ones.

How to replace crankshaft G4FA Hyundai Solaris

Inspecting the crankshaft. Cracks are not allowed.

On the surfaces mating with the working edges of the seals, there should be no scratches, nicks, scratches. If they are found, we replace the shaft.

We measure the outer diameter Dn of the main journals with a micrometer.

The actual clearance between the main bearing shells and the crankshaft main journals is determined in the same way as described in the article "Hyundai Solaris Repair of the connecting rod and piston group of the Hyundai Solaris engine"

The nominal gap is 0.018-0.045 mm, the maximum allowable gap is 0.1 mm.

If the actual design gap is less than the limit, you can reuse the bearings that were installed.

If the gap is greater than the maximum allowable, we replace the liners on these journals with new ones, selecting them according to the class of the nominal diameter of the crankshaft main journals

The main journals of the crankshaft are divided into three classes according to the nominal diameter:

  • - class 1 (Dн = 47.960–47.954 mm);
  • - class 2 (Dн = 47.954–47.948 mm);
  • - class 3 (Dн = 47.948–47.942 mm).

The end surfaces of the main bearing shells of classes 1 and 3 are marked in different colors: class 1 bearings are black, class 3 green.

Class 2 inserts are not marked.

Check the parallelism of the thrust collars of the middle main journal of the crankshaft: if they are not parallel, the shaft is bent and needs to be replaced.

We wash the channels of the crankshaft, for this we pour kerosene into the radial channels, having previously drowned them out on one side with wooden plugs.

We stand for about 30 minutes and wash the channels with gasoline.

Repeat flushing until clean gasoline flows out through the connecting channels.

How to replace crankshaft G4FA Hyundai Solaris

We lay the upper main bearing shells in the bed of the cylinder block

Set the inserts so that the antennae of the insert is aligned with the notch in the bed

How to replace crankshaft G4FA Hyundai Solaris

Lubricate the liners with engine oil

We put the crankshaft in the cylinder block

How to replace crankshaft G4FA Hyundai Solaris

Install the thrust half rings of the middle crankshaft bearing

Install the front thrust half ring with grooves towards the front of the engine (towards the timing chain)

We put the lower liners in the main bearing caps, aligning the antennae of the liners with the recesses on the caps.

Lubricate the crankshaft main journals with engine oil

Lubricating the crankshaft main bearing shells

We install the main bearing caps according to the serial numbers

To install bearing caps, use a soft-faced hammer.

It is forbidden to install the covers by tightening the fasteners, since in this case the seating surfaces of the covers and the cylinder block will be damaged

Tightening order for the crankshaft main bearing cap bolts

Install the cover bolts, tighten with a torque of 17.7-21.6 Nm in the order shown in the figure

We tighten the bolts of the covers at an angle of 88-92 ° in the same order.

Before installing the crankshaft bearing cap bolts, measure their length from the bottom of the head to the end.

If the bolt length is more than 75.3 mm, replace the bolt

Measuring crankshaft end play

Check the axial clearance of the crankshaft, it should be 0.05-0.25 mm.

The maximum allowable gap is 0.4 mm.

If the gap is greater than the maximum allowable value, we replace the crankshaft thrust washers.

Install all parts in reverse order.