[Blue-S]

The 1971 Fiat 124 Spider with the 1608cc is most Fiat buffs' favorite early (chrome bumper) US-market spider. Nice car! I haven't worked on a 124 Spider for almost 20 years, but I did engine work on all the Spiders that I owned from 1986-1991. I still have a couple of 1800 cylinder heads and some other stuff in the garage!

The auxiliary shaft drives only the oil pump and the fuel pump on the 1608cc engine, because the distributor is up on the exhaust cam tower and is driven from the exhaust cam. You don't really have to time the aux shaft exactly on the 1592, 1608 and 1756cc twincams; only the 1979-1982 2.0L engine in the 2000 Spiders is capable of having interference issues between the fuel pump lobe on the aux shaft and the crankshaft. This is DEFINITELY an interference engine -- pistons can hit valves if the timing is off badly enough. Intake and exhaust valves can hit each other, too.

You COULD try to install the timing belt and carefully turn the engine over by hand, feeling for interference. If I were in your situation, I would rather set the crank & cams to the timing marks, then install the belt. To do this, first verify that all of the pistons are NOT at top dead center. You can do that by pulling all of the spark plugs and dropping a LONG phillips screwdriver or 1/4" drive socket extension (like 12" long) down the #1 spark plug hole. Verify the height of the screwdriver (by eyeball or measurement) then do the same with the screwdriver in the cylinder #2 spark plug hole. Carefully turn the crankshaft slightly to see if the piston is going up or down. You want to have the "higher" piston going down, and the "lower" piston going up. You don't need to move it a lot -- just ensure that none of the piston pairs (cylinders 1 & 4 or cylinders 2 & 3) is close to its highest point of travel.

With all the pistons significantly below deck, you can turn the cams without worrying about crashing a valve into a piston. Use a wrench (not a ratchet) to very carefully turn one of the cams so that the timing hole in the cam sprocket lines up with the pointer that is built into the timing cover mounting bracket. You need to use a wrench while turning the cam so that you can keep the cam's motion under control - it may try to "snap" ahead at certain points of rotation due to the position of the cam lobes. If you feel a hard resistance point, STOP because you have a valve hitting another valve that is being held open by the other cam. You may have to juggle both cams a bit in order to avoid crashing valves into each other while moving toward lining up the timing holes in both cam sprockets with the pointers that are built into the timing cover's upper mounting bracket.

Now that both cams have been lined up (and no valves were bent in the process), carefully turn the crankshaft so that the crank timing sprocket's timing mark is lined up correctly. I can't remember what that mark looks like, but since you have a factory manual you should have a pretty good idea of what to look for. For bonus points, align the aux shaft sprocket more-or-less where they show it on the timing illustration. Next, install and tension the belt. Turn the crankshaft over TWO revolutions by hand, checking for any abnormalities. Your timing marks should line up after two revolutions of the crank. If not, then one of the components was not timed correctly. If the aux shaft timing mark is off a bit, it doesn't matter on the 1608, so don't worry about it. Once you get it running, you should dig out your timing light and verify the ignition timing. I always liked 10 degrees BTDC at idle. It's simple to set, because the distributor has centrifugal advance so there are no vacuum lines to plug. If it still has the points ignition, you should check (and possibly adjust) dwell BEFORE setting ignition timing.

Enjoy!

BTW -- The green Spider shown above could be a 1968 or 1969 US-market car, since those did have the wonderful little round side markers. The Euro market Spiders seemed to keep the round side markers for the majority of their model run. The green car also shows evidence of mounting holes for the US-market front bumper over-riders...which were not on Euro cars.

- Greg