The only element that has changed since he was outside the car for a few minutes is the carburettor and that's why I was interested in him from the start. There is also that it now has to drive the gearbox in neutral but without the wheels and there is the full exhaust.
The engine started easily and ran not too badly, in any case much better than now but only a few tens of seconds because there was no cooling, only the full water and the closed circuit swirl tank overflowed quickly. I still managed to set the initial advance to 10°.
There was no backfire.
Since then it has remained a year and a half without turning, the valves are made of stainless steel but could the cast iron seats rust and no longer be watertight?
The new carburettor is all black and full of soot from backfires.
I have to unscrew the 4 idle mixture screws by about 1.5/2 turns and screw the idle speed screw all the way in for it to start, once started I can unscrew the idle speed screw and it runs better when I close the idle mixture screws almost full wealth. If before trying to start I open the primaries just once to get a slight squirt from the accelerator pump, I'm sure to have a backfire on the first turn of the starter.
I also thought about changing the spark plugs and I'm going to check the clearance between the rocker arms and the valves before temporarily fitting the old carb.