Yes, the prototype was mostly tested with the Bernard diesel.
This engine was a bit intriguing, firstly because it was the only french diesel ever used on a voiturette ! Then it was a very light unit (24 kilos without oil) and almost the smallest ever seen on a road vehicle (only superseeded by the Yanmar L40 AE 199cc, seen on the first Microcar 50 LD-GLD). But it wasn't really ready made for a small car, as it didn't had any electric starter.
In fact, the only brand who has used it a bit on a few cars was Erad. They had really tried about every engine that was available in these days, Sachs, Motobecane, BCB, Farymann, Lister-Petter...
Daniel Renard built about 130 Capucine 4/50 D with the Bernard. But again it wasn't well suited for a road car, and a bit underpowered as well.
The funny thing is that Bernard Moteurs bought out Erad later, in 1994.
![Grin ;D](https://www.autopuzzles.com/forum/Smileys/default/grin.gif)
But for the Noval, it should have been one of the first diesel voiturette available on the market. Sadly (or not !
![Cheesy :D](https://www.autopuzzles.com/forum/Smileys/default/cheesy.gif)
), Noval stopped everything very early, and the car wasn't even typed approval by the Mines.