My first impression was that the model was actually in a relatively decent condition. However, it did not run very well. The engine kept stopping, especially at slow speeds. Therefore, the engine was badly in need of maintenance.
For maintenance purposes, I took the V221 apart. I cleaned most of the parts ultrasonically. However, this was not possible for all parts as, for instance, lettering and paint on the body may flake off.
After the ultrasonic cleaning, I had to remove the corrosion from the contact points. The best thing for this is sandpaper.
Once I had put the engine back together again, I did a test run. This was successful.