Riello burner problem on Lyka serial 2

We have a little problem here in Sweden, mine and Kalles Lyka have the same problem. The question is if any more have the same effect and if we can do something about it. When we start the burner it stops after about 15 seconds with a little dieselcloud and start after about 15 second and that is reapeted until the the pressure is ok. Longer periods when the pressure is raising. When the pressure is full and we drive the car the burner is working ok but sometime the burner i making a brake and the pressure is a bit low for speeding on uphill.
Intersesting to hear your experience and solution.
Its a bit nervous if its going to work or not but the heating up is a bit softer now.
Rolf Johansson

Sounds like at startup you do not have enough "head space" in the boiler - meaning it is too full of water. If this is not the case, then possibly a sporadic air leak in the fuel lines thereby starving the burner? I would think if you were leaking air into the fuel line, it would also stop the burner completely and no fuel would get to the burner. As far as going up hills, my Lyka will slow down on moderate hills until the steam pressure recovers. Also, I get a top speed around 18 mph on flat grade.

The problem was found when the burner totaly stop. I change the fotocell in the burner and now its working perfect.
The fotocell didnt react when I measured it with a multimeter.