Installing and checking clearances in connecting rod bearings (Nissan Sunny B13)

Attention! The description concerns only connecting rod bearings of standard size. Repair connecting rod bearings are not divided into size groups.

New connecting rod bearings are selected according to the size group codes marked on the crankshaft.

The size group codes are applied either on the crankshaft cheek next to the journal of the 1st cylinder (from the camshaft drive chain side), or on the cheek near the neck of the 4th cylinder (from the flywheel or torque converter drive disk side). The four-digit code indicates the size groups of the crankshaft connecting rod journals, the first digit refers to the journal of the 1st cylinder, and the fourth to the journal of the 4th cylinder. The five-digit code refers to the size groups of the main crankshaft journals (see subsection 3.2.2.8.2).

To select connecting rod bearing liners, you need to know the size group of the crankshaft connecting rod journal for a given cylinder, and then use the attached table to determine the required liners, focusing on the color marking, which is applied as a dot on the side surface of the liners.

Code on the crankshaft	Color marking of the insert size group
0	black
1	brown
2	green

Checking the clearance in connecting rod bearings

1. Clean the outer surface of the connecting rod bearings and the surfaces of the bearing bores in the connecting rods and in the connecting rod caps.



2. Press the bearing shells down to place the upper and lower shells in their places. Make sure that the projections on the bearing shells fit into the grooves in the connecting rod (indicated by arrows) and in the connecting rod cover.



3. When installing the bearings, do not touch the working surface of the bearings with your fingers. Make sure that the oil hole in the upper connecting rod bearing is precisely aligned with the hole in the connecting rod. If the clearance check is to be performed with old bearings, make sure that these bearings are installed in their original places.

4. The clearance in the connecting rod bearings can be checked in two ways. When determining the clearance in the first way, it is necessary to assemble the caps with the connecting rods and connecting rod bearings, ensuring the correct mutual orientation of these parts. Tighten the connecting rod cap nuts with a specified torque and measure the inner diameter of each assembled pair of liners using a bore gauge with a dial indicator or a caliper. The clearance in the main bearings is determined as the difference between the inner diameter of the assembled connecting rod bearings and the diameter of the corresponding connecting rod journals of the crankshaft.

5. The second way (more accurate) consists of using a round plastic Plastigage calibration wire laid on carefully cleaned surfaces of the crank journals.

6. Install the connecting rod bearings, orienting them correctly. Place a piece of calibration wire on each connecting rod journal of the crankshaft.

7. Clean the surfaces of the connecting rod bearings and install the connecting rods on the corresponding crankshaft journals. Install the connecting rod bearing caps, orienting them according to the existing marks or marks applied during disassembly.



8. Tighten the cover nuts (see below). When tightening, changing the position of the wire is not allowed, and turning the crankshaft is also not allowed.

9. Remove the connecting rod caps, being careful not to turn the crankshaft or move the gauge wire. Compare the width of the flattened wire with the scale on the package and determine the clearance in the main bearings.

10. If the clearance differs from the standard, the reason may be the incorrect selection of connecting rod bearings (or their increased wear if the liners tested were previously in use). Before deciding whether the bearings need to be replaced, make sure that there is no dirt or oil between the surfaces of the caps or connecting rods and the bearing when measuring. If the width of the flattened wire is greater on one side, this indicates that the connecting rod journal is taper.

11. If the clearance differs from the norm when measured with old liners, then repeat the measurements with new liners. If the clearance exceeds the norm even with new liners, then you should consult the dealer's service department or a specialist in this engine to get advice on how to proceed. It may be necessary to regrind the crankshaft journals and replace the liners with repair ones.

12. If necessary, purchase liners of the appropriate size group and repeat the procedure for measuring the clearance in the connecting rod bearings.

13. When finished, scrape off any remaining calibration wire from the crankshaft journals with your fingernail or a wooden chip, without damaging their surface.

Installation of connecting rod and piston group

The following description is given on the assumption that assembly will be performed after the crankshaft assembly with all main bearings and caps has been installed (with a frame of lids).

1. Make sure the connecting rod bearings are installed correctly (see points 4 and 5). If new bearings are to be installed, carefully remove any remaining preservative grease by washing them in kerosene. Wipe the connecting rods and bearings dry with a lint-free cloth.

2. Make sure that the piston ring joints are correctly positioned and compress the rings using a special tool.

3. Lubricate the cylinders, pistons and rings, then lay out the pistons and connecting rods in the order in which these parts will be installed on the engine.



Start assembly with cylinder 1. Make sure the piston ring joints are correctly positioned (see Fig. subsection 3.2.2.12) and squeeze the rings with a special device.



5. Insert the piston assembly with the connecting rod into the first cylinder. Orient the piston so that the mark on the piston bottom (in the form of an arrow or a line) was facing the camshaft chain drive cover. Lightly tap the piston with a hammer handle or a wooden block so that the piston enters the cylinder and the piston bottom is aligned with the split plane of the cylinder block.



6. Make sure the connecting rod bearings are installed correctly and generously lubricate the bearings and the crankshaft journal. Carefully, so as not to damage the cylinder surface, pull the connecting rod to the crankshaft journal. Put on the connecting rod cap with the bearing and tighten the nuts by hand. Keep in mind that the planes on the connecting rod and on the connecting rod cap, on which the marks are applied, must align (this means that the mounting lugs of the connecting rod bearings are located opposite each other).


7. Tighten the connecting rod cap nuts to the 1st stage torque using a torque wrench and socket head (photo on the left). Then tighten the nuts to the 2nd stage tightening angle, or if you don't have a wrench with an angle scale, tighten to the 2nd stage torque (photo on the right).



8. Rotate the crankshaft and check for freedom of rotation. If new parts are installed, there should be a noticeable constant resistance to the rotation of the crankshaft, but the crankshaft should rotate smoothly without jamming.

9. Install the remaining pistons and connecting rods in the same manner.

10. Install the cylinder head, timing chain(s) and oil pan.

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