The engine room of a GSA. A usual comment from first-time buyers is "where is the engine?". Well, actually, it's there, under the air cleaner, carburettor and the mess of hoses at the very front of the car.
The engine room of a GSA. A usual comment from first-time buyers is "where is the engine?". Well, actually, it's there, under the air cleaner, carburettor and the mess of hoses at the very front of the car.
All GSA models are equipped with a flat four (4-cylinder boxer) air cooled engine. In the first versions on the Swedish market (1980) the same 1222cc 59 hp engine was used as in the GS. Then, around 1981, the slightly larger 1299cc (65 hp) (often called the "1300-engine") engine appeared in all GSA versions. The difference isn't enourmous, and I guess the 1300-engine was a attempt to squeeze the last ounce of power from the design. The 1300-engine made its debut already in the GS X3 which appeared in 1979. In some countries, a slightly less powerful 1129cc engine was used for the simpler models, although it never found its way to Sweden.
The engine's origins can be traced to the flat twin from the 2CV, which had been upgraded with two more cylinders and overhead cams. The design is a bit awkward, and many a car mechanic has probably sworn at some of the design trade-offs (as have their customers, when they see the bill!), like the fact that the fan is attached with a 42 mm nut, or that the carburetter and half the intake manifold must be dismantled in order to replace the starter motor, or that the whole engine must be lifted out of the car to replace the cylinder head return oil pipe gaskets, which usually start to leak after about 100-120 000 km.
Myself, I see it from a more hopeful angle...the fact that the fan is mounted on the engine crankshaft means that it won't stop turning as the result of slipping or broken belts. Water and anti-freeze are not necessary with the air-cooled design. The engine is mounted in front of the front wheels which makes oil changes a snip (and the oil plug uses the same 21 mm key as the spark plugs do) - by using the car's own variable ground clearance the car can be raised sufficiently to get a decent-sized container under oil plug without having to lift the it. The low-mounted engine also gives superior road handling (low center of gravity).
Around 1981 the anti-pollution laws for cars in Sweden were changed in order to further reduce the harmful effect of exhaust gases on the environment. This resulted in a more advanced anti-pollution system on [Swedish sold] GSA's as well. As early as 1976 (well, early for Europe), the GS had been equipped with an EGR valve, recirculating exhaust gases once the engine had gotten warm. The same system was used in early GSA's, but in 1981 a complex network of vacuum hoses and electrically operated valves showed up around the carburettor. In the yearly compulsory car testing procedure in Sweden (the 'kontrollbesiktning') the interest is however still focused on the EGR valve, which is a good job since the rest of the system has a tendancy to stop working, completely or in parts...
The biggest advantage of the 1981 design is a fast idle system which makes it possible to fully depress the choke control after only a minute or so - the throttle is kept open using a vacuum-operated device until the engine is warm - a form of automatic choke. Most mechanics don't understand the fast idle system, which results in the connections to the fast idle control valve being simply disconnected...
The GSA engine is designed for slightly higher RPM's than conventional engines, and many perceive it as noisy. Myself, I find it has a cosy whooshing sound, compared to modern cars where the attempts to reduce engine noise have failed sorely in the 100 Hz area, which causes painful head vibrations for the poor souls inside the car...something that was strongly brought to my attention after a short but painful trip in the back seat of an Audi...
One problem with the engine is however that the camshafts tend to wear down. The result is a more-or-less loud chattering from the engine. The engine doesn't mind; it runs just as well, and you can drive for a long time with worn-out cams. The greatest problem is that you can get tired of the noise after a while...