Avia A21: the 1983 modernisation of Czechoslovakia’s light truck

The Avia A21 was the 1983 modernisation of Avia’s Saviem-licensed light truck and replaced the A20 at the Letňany works near Prague. It kept the 3.6-litre four-cylinder diesel but gained a five-speed gearbox, and from 1993 turbocharged A21T versions met the Euro 1 emission standard.

Avia A21 at a glance

The A21 has no article of its own; it is described in the Avia company history on English Wikipedia and in the Czech Wikipedia article on the A 15 / A 20 / A 30 series.

History of the Avia A21

Avia bought licences from Renault-Saviem in 1965 and began series production of the two trucks in autumn 1968: the larger SG 4 Super Galion became the Avia A30 and the smaller SG 2 Super Goelette became the Avia A15. The vehicles were built at Letňany, with engines, cabs and chassis assembly there and bodies supplied by the affiliated plants at Heršpice, Ivančice and Žilina.

In 1979 the A15 was modified to carry 250 kg more and was renamed Avia A20. At the beginning of 1983 production of the A20 and A30 ended, and after substantial changes to the engine, gearbox, steering, frames, cab and platform body the trucks were designated Avia A21 and Avia A31. The most important change for drivers was the five-speed gearbox, which replaced the four-speed unit of the earlier models; the A21 also kept single rear wheels, while the heavier A31 had twin wheels.

The 712.18 engine

The A21 used the 712.18 four-cylinder diesel: 102 mm bore and 110 mm stroke, 3,595 cc and 61 kW. It belonged to the same family as the engines of the A15 and A20, water-cooled four-stroke units with MAN combustion chambers, cast-iron block and head, OHV valve gear and an in-line injection pump. The chassis was built in three frame lengths, marked N (3,240 mm wheelbase), K (2,680 mm) and L (3,640 mm), which allowed platform trucks, box bodies, tippers and special bodies to be built on the same basic vehicle.

Turbocharged A21T

At the beginning of 1993 the naturally aspirated 712 engines were replaced by turbocharged D407 engines with a higher torque output that met the Euro 1 standard. Vehicles with these engines were sold as A21 Turbo, or A21T. In the same period the cab was improved with a modified chassis, a strengthened drive unit, power steering and a redesigned interior.

The 1996 update and the end

The last major revision came in 1996, when Avia used solutions prepared for the new A60/A70/A75/A80 range. The D421.76.01 engine met Euro 2 and brought a Bosch rotary injection pump, new injectors, pistons and cylinder head. The dashboard was completely new, and the most visible external change was a black plastic radiator grille with round headlights. Production of this version ended at the end of 1998.

The A21 chassis was also used for buses: in 1987 the Croatian firm TAZ of Zagreb built the TAZ Neretva, a 14-seat minibus 5.34 m long, and several were tested in Czechoslovakia, including an ambulance conversion.

Design and features

• Five-speed gearbox: the main mechanical improvement over the A15/A20, with the gear lever under the steering wheel until it moved to the floor in 1988.
• 3,595 cc diesel: the 712.18 engine of 61 kW, shared with the A31.
• Three wheelbases: N, K and L frames let the same cab carry platform, box, tipper or special bodies.
• Turbo option: the A21T of 1993 offered 65 kW and Euro 1 compliance.
• 1996 facelift: Euro 2 engine and a black grille with round headlights.

Avia A21 versions

• A21 (1983–1998): chassis-cab and platform truck, the standard model.
• A21 F: furgon (van) body on the A21 chassis.
• A21T (1993): turbocharged D407 engine, 65 kW, Euro 1.
• 1996 specification: Euro 2 engine, new dashboard and black grille.
• TAZ Neretva (1987): 14-seat minibus built in Zagreb on the A21 chassis.

The heavier Avia A31 shared the cab and engine range, and the van-bodied versions are described in Avia furgon. More models are in the Avia collection.

Sources

• Avia Motors, English Wikipedia: licence history, A21T, 1996 update
• Avia A 15 / A 20 / A 30, Czech Wikipedia: 1983 modernisation, engine, gearbox, axles, versions, TAZ Neretva