Pistons and connecting rods - examination and renovation

Engine repair procedures - 1.05 and 1.3 litre pre August 1985 / Pistons and connecting rods - examination and renovation

1 Examine the pistons for ovality, scoring and scratches. Check the connecting rods for wear and damage.

2 To remove the pistons from the connecting rods, first mark the two components in relation to each other. The indentation on the bearing end of the connecting rod faces the same way as the arrow on the piston crown (see illustration).

23.2 Indentations on big-end bearings (arrowed) must face same way as arrow on piston crown

3 Prise out the circlips then dip the piston in hot water. Press out the gudgeon pin and separate the piston from the connecting rod.

4 Assemble the pistons in reverse order.

5 If new rings are to be fitted to the original pistons, expand the old rings over the top of the pistons by using three old feeler blades to prevent the rings dropping into empty grooves.

6 Before fitting the new rings, insert each of them into the cylinder bore approximately 15.0 mm from the bottom and check that the end gaps are as specified (see illustration).

23.6 Checking piston ring gaps

7 When fitting the rings to the pistons, ensure that the TOP markings face towards the piston crown and arrange the end gaps at 120° intervals (see illustration).

23.7a Space ring gaps at 120° intervals

Using a feeler
blade, check that the clearance of each ring in its groove is within the limits specified (see illustration).

23.7b Checking piston ring-to-groove wall clearance