This DIY repair manual by Haynes, covers 1968-1978 Fiat 124 Sport Coupe and Spider 1400, 1600, and 1800. 4-speed and 5-speed manual transmission versions. Note: This manual does not cover the Fiat 124 Special Sedan models.
Book Excerpt: 1968-1978 Fiat 124 Sport, Coupe, Spider Repair Manual ENGINE

PISTON | REPLACEMENT

1. Lay the piston and connecting rod assembly in the correct order ready for refitting into their respective bores. There are numbers stamped on the big end bearing bosses as shown in the photo.
2. With a wad of clean non-fluffy rag wipe the cylinder bores clean.
3. Position the piston rings so that their gaps are 120 degrees apart and then lubricate the rings.
4. Fit the piston ring compressor to the top of the piston, making sure it is tight enough to compress the piston ring.
5. Using a piece of fine wire double check that the little jet hole in the connecting rod is clean.
6. The pistons, complete with connecting rods, are fitted to their bores from above.
7. As each piston is inserted into its bore ensure that it is the correct piston - connecting rod assembly for the particular bore and that the connecting rod is the right way round, also that the front of the piston is towards the front of the bore, i.e. towards the front of the engine. Lubricate the piston with clean correct grade oil.
8. The piston will slide into the bore only as far as the bottom of the piston ring compressor. Gently tap the top of the piston with a wooden or plastic hammer while the connecting rod is guided into approximate position on the crankshaft. (photo).

IGNITION SYSTEM

DISTRIBUTOR | INSPECTION AND REASSEMBLY

1. Having removed the distributor cap, lift away the rotor arm (on some distributors the rotor arm is on a disc secured by two screws to the shaft assembly).
2. Remove the contact breaker points as described in Section 4 of this chapter.
3. The contact breaker mounting plate is removed after undoing the two screws which retain it to the distributor body. Once this plate is removed the centrifugal advance mechanism is exposed. (see photo).
4. If the centrifugal advance mechanism and or the distributor shaft in the body are found to be worn and sloppy, you should check whether spares are available and consider an exchange distributor. Very often in fine mechanisms as distributors, it will not be a case of needing to replace just one component. (see photo).
5. The center shaft is removed after drifting out the parallel pin which secures the shaft lower collar in position. Remove the washer from under the collar and slide out the shaft.
6. Check the contact breaker points as described in Section 2. Check the distributor cap for signs of tracking, indicated by a thin black line between the segments. Replace the cap if any signs of tracking are found.

Subject: 1968, 1969, 1970, 1971, 1972, 1973,1974, 1975, 1976, 1977, 1978 Fiat 124 Sport, Coupe, Spider service, maintenance, repair. ISBN-10: 0900550945 | ISBN-13: 9780900550942 | Haynes 34010