Citroën Dyane Fuel Tank and Fuel System
The Citroën Dyane essentially had two different fuel tank sizes, which changed over the course of its production run (1967–1983). The tank versions in detail:
- 20 liters (metal): The early Dyane models (particularly the Dyane 4 with a 425 cc or 435 cc engine) were equipped with a 20-liter metal tank. This was standard for Citroën’s early A-series models, such as the 2CV.
- 25 liters (metal or plastic): Later models, particularly the popular Dyane 6 (602 cc), were fitted with a larger 25-liter tank to increase range.
Comparison by model type
Model: Tank capacity (approx.): Material:
- Dyane 4: 20 liters: Metal
- Dyane 6: 25 liters: Metal (plastic)
The connection from the fuel tank to the engine on the Dyane
A flexible yet rigid plastic hose connects the fuel tank to the mechanically driven fuel pump.
Are there different fuel pumps for the Dyane?
There were differences in the fuel pumps: The first models had a horizontal inlet, while later models with 602 cm³ engines (M28 engine) only had fuel pumps with a bottom inlet and vertical fuel delivery to the carburetor.
We carry all fuel pumps, fuel lines, fuel pump pushrods, and spacer plates for every 2CV - Dyane engine as new parts. Fuel pumps with additional manual operation are also available in our inventory.
Does the Dyane have a fuel return line?
What all 2CV, Dyane, Mehari, and AMI models have in common is the absence of a fuel return line to the fuel tank. The excess fuel produced when starting the engine is drained through the intake manifold. At its lowest point, beneath the carburetor, the manifold has a drain hole through which the fuel drips out over the engine block. This is why you smell gasoline during unsuccessful starting attempts.
It is extremely important that this drain hole is never blocked. If it becomes clogged, fuel accumulates in the intake manifold and can vaporize, which in the worst case can lead to a fire in the 2CV.
What can you do if you need to start the Dyane after it has been sitting for a long time?
Here’s a tip: If the Dyane has been sitting for a long time, gasoline flows back from the pump into the tank. This causes the fuel pump’s diaphragm to dry out quickly. When you start the engine, it then takes a very long time for the fuel to be drawn in (and sometimes it doesn’t work at all). To fix this, simply remove the fuel cap and, while a second person starts the engine, blow forcefully into the tank (place your lips on the fuel filler neck!). This creates positive pressure in the tank, which pushes the fuel forward toward the fuel pump.
Are there any other tips?
We also carry a fuel filter with a check valve as an upgrade. This prevents the fuel from flowing back so easily.
We also carry fuel additives that can be added during a long planned downtime (winter break). These prevent the formation of acids in the fuel for a very long time. Additionally, you should only use Super Plus gasoline.