Pistons and connecting rods - examination and renovation
1 Examine the pistons for ovality, scoring, and scratches. Check the connecting rods for wear and damage. The connecting rods carry a letter indicating their weight class; all the rods fitted must be of the same class.
2 The gudgeon pins are an interference fit in the connecting rods, and if new pistons are to be fitted to the existing connecting rods, the work should be carried out by a Ford dealer who will have the necessary tooling. Note that the oil splash hole in the connecting rod must be located on the right-hand side of the piston (the arrow on the piston crown faces forwards).
3 If new rings are to be fitted to the existing pistons, expand the old rings over the top of the pistons. The use of two or three old feeler blades will be helpful in preventing the rings dropping into empty grooves. Note that the oil control ring is in three sections.
4 Before fitting the new rings to the pistons, insert them into the cylinder bore and use a feeler blade to check that the end gaps are within the specified limits (see illustration).
33.4 Checking a piston ring gap at the top of the cylinder bore
5 Clean out the piston ring groove using a piece of old piston ring as a scraper. Be careful not to scratch the aluminium surface of the pistons. Protect your fingers - piston ring edges are sharp.
6 Fit the oil control ring sections with the spreader ends abutted opposite the front of the piston. The side ring gaps should be 25 mm (1.0 in) either side of the spreader gap. Fit the tapered lower compression ring with the “TOP” mark towards the top of the piston and the gap 150º from the spreader gap, then fit the upper compression ring with the gap 150º on the other side of the spreader gap. Note that the compression rings are coated with a molybdenum skin which must not be damaged.
Note also that the compression rings are made of cast iron, and will snap if expanded too far.
See also:
Distributor lubrication - models with contact breaker
distributor (Every 6000 miles or 6 months)
1 Remove the distributor cap and the rotor
arm.
2 Apply a couple of drops of light oil to the
felt pad in the top of the shaft.
3 Wipe clean the distributor cam, then apply
a trace of high meltin ...
Radiator fan thermal switch - testing, removal and refitting
Testing
1 The thermal switch is located on the side of
the thermostat housing on early OHV engine
models and in the thermostat housing cover
on later OHV versions. On all CVH engines, the
switch ...
Intensive maintenance
If, from the time the vehicle is new, the
routine maintenance schedule is followed
closely and frequent checks are made of fluid
levels and high wear items, as suggested
throughout this manual, th ...