🧰 How to Identify Which Classic Fiat 500 Engine & Carburettor You Have
Owning a classic Fiat 500 is a joy — but when it comes to ordering the correct parts, it’s crucial to know exactly which engine version you have. Over the years the Fiat 500 had several engine variations; although they may look similar, there are key differences that determine which carburettor, distributor cap, and rotor arm your car uses. This guide will walk you through the process step-by-step.
🔧 Where to find your Fiat 500 engine code
Every classic Fiat 500 engine has its identification number stamped just to the lower right of the mechanical fuel pump. This area can be covered in oil and grime after decades of use — carefully clean the area with a rag and degreaser to reveal the code.
Fiat 500 engine codes
| Fiat 500 Model | Engine Capacity | Engine Code | Years of Production |
|---|---|---|---|
| N (Nuova) | 479cc | 110.000 | 1957–1960 |
| D | 499cc | 110D.000 | 1960–1965 |
| F | 499cc | 110F.000 | 1965–1972 |
| L (Lusso) | 499cc | 110F.000 | 1968–1972 |
| R (Rinnovata) | 594cc | 126A5.000 | 1972–1976 |
| Giardiniera | 499cc (flat) | 120.000 | 1960–1977 |
If your engine code doesn’t match the model on the car, it likely means an engine swap has taken place.
🔄 Common engine swaps — Fiat 126 engines
The most common replacement engine in classic Fiat 500s is the Fiat 126 engine. Here are typical 126 engine codes you might see:
| Engine Code | Engine Capacity |
|---|---|
| 126A.000 | 594cc |
| 126A1.000 | 652cc |
| 126A2.000 | 704cc (water-cooled) |
Once you’ve identified your engine code, you can choose the correct parts or service kit for it.
Click Here To Browse Engine Service Kits
Click Here To Browse All Ignition Parts
🔍 How to identify your carburettor
After confirming your engine code, identify the carburettor. Classic Fiat 500s commonly use Weber or Dell’Orto carburettors. The model number is stamped on the side of the carb body (for example: 26 IMB 10).
Common carburettors & rebuild kits
- Weber 26 IMB — Classic Fiat 500 Carburettor Rebuild Kit for 26 IMB 10
- Weber 28 IMB — Classic Fiat 500 / 126 Carburettor Rebuild Kit for 28 IMB
- Weber 26 OC 10 (Giardiniera) — Giardiniera Rebuild Kit for Weber 26 OC 10
- Dell’Orto 28 — Classic Fiat 500 / 126 Carburettor Rebuild Kit for Dell’Orto 28
The carburettor spacers are also important for these engines. You need to make sure you have the correct one for the carburettor!
Click here for the IMB 26 spacer
Click here for the IMB 28 spacer
If you have recently refurbished your carburettor and it is still running badly, check if you have the correct spacer drip tray as this has huge effects to the carb!
If you are ever unsure or need technical advice, feel free to get in contact with us!