Home / All posts / 1930 – Rochet-Schneider 26-Six: engine tuning

1930 – Rochet-Schneider 26-Six: engine tuning

 The engine was rebuilt during the summer-fall 2022 period. It was reassembled on the car in December but we are having some problems getting it running again.

It took David, our mechanic, three days of full time work to put the engine back in the car.
After the 450 kgs of steel and cast iron had returned to their place, the restart did not give us complete satisfaction: the engine did not run smoothly.

Let’s say it right away, the work of the “Atelier de la Belle Epoque” is not to be questioned. The engine had been bench tested for several hours and several dozen liters of fuel.

The symptoms

The symptoms observed are: black smoke and irregular ignition cycle. In other words: too rich a mixture.

The hypotheses

The following hypotheses were considered:
– burnt out spark plugs after a failed first start
– ignition settings (remember that the 26-6 has a dual ignition: magneto and coil)
– jets too big
– modern gasoline too fluid compared to the old ones
– carburetor adjustment/overhaul
– …

Upcoming tests 

We have ordered several different sets of spark plugs, we will test them first next Friday and review the carburetor setting at the same time.

Next step

We hope to be able to give you some news in the next ten days. See you soon!


Thanks to Pierre Vinoy, our very faithful electrician, to Pascal Chaumont, the great specialist of spark plugs and magnetos and fraternal thanks to all the members of the Rochet-Schneider club who mobilize themselves to bring us their help: the task is not easy. Only two examples of the 26-six are known to this day and no instructions for its carburetor are available.