Fiat Spider Timing Belt Replacement
Article by Mark Trotta
The Fiat Spider was one of the first production cars to feature a timing belt versus a timing chain. Rubber belts are lighter, quieter and more efficient than metal chains, but usually require more frequent replacement.
Timing belts can and do break. They also stretch and wear, then slip on the cogs. This will result in bad performance or a no-start condition.
____________________________________________
____________________________________________
Free-Running vs Interference Engines
Timing belt engines fall into one of two categories, "free-running" and "interference".
If the timing belt breaks on a free-running design, the engine will stop and you will need to be towed home. There is enough clearance between the pistons and valves so no mechanical damage usually occurs. The installation of a new belt is usually all that is required.
If a timing belt breaks on an interference engine, mechanical engine damage will occur. The damage usually involves the pistons hitting open valves, resulting in the need for expensive repairs.
*********************
Fiat 2.0 Timing Belt
My reason to remove and install the Fiat Spider timing belt was to get to the leaking cam cover gasket on the exhaust-side of the motor. Both the distributor and the timing belt had to be removed to perform this service.
Removing The Old Timing Belt
First, carefully mark how the distributor comes out - there seems to be a discrepancy in the shop manual. The radiator is easily removed, and gives better access to the front of the motor. Removal of the old timing belt is then fairly straightforward.
____________________________________________
____________________________________________
Installing The Timing Belt
Installing the new timing belt was a bit tricky - it took me several tries to get the crank pulley, auxiliary shaft sprocket, intake cam sprocket, and exhaust cam sprocket perfectly lined up before installing the new timing belt. A 38mm socket is helpful for turning the crank (with the transmission in neutral).
The picture above shows my "timing belt installation tool". It's nothing more than a hammer and a triangular-shaped piece of wood to help me wedge the tensioner over another millimeter or two, just enough to slip the belt on and off while making sure all four timing marks were lined up properly.
*********************
Notes and Misc
The heart of every classic sports car lies underneath the hood, and the Fiat Spider's 2.0L twin-cam engine is a good one. The iron-block, aluminum-head engine was designed by Aurelio Lampredi, who had worked for Ferrari during their successes in the early fifties. With a three-decades long production run, the Fiat twin-cam engine is of the longest-produced automotive engines to date.
Replacing the timing belt on our 1979 Fiat Spider was a frustrating job. But with the teeth on all the cogs exactly right, the car ran much better than it before!
*********************
Related Articles:
Fiat Spider Brakes
Best Oil for Classic Cars
