Belgian Super Punch restoration
I've started to dismantle my mower, all works quite well, except for that lever on the left side. There's a clutch that can only be disengaged by a screwdriver. The handle is just to short to put any power on it to be able to disengage it. What am I doing wrong ? Oh yeah, the lever serves to put on/off automatic driving mechanism.
You are doing nothing wrong, it has been quite a few years now since I had to deal with this problem, but I remember that it was quite common. You need to strip down the mechanism and clean everything up until the mechanism moves freely, then fully rebuild the mechanism, lubricating everything well.
What's strange to me : the lever outside the machine is much shorter than the part on the inside. Additional the lever is even being bend. As I see it, not a smart way to make things going easy.
Another question : has anyone an idea of the RAL-number of the green paint ?
.In addition to the advice from Hortimech, check for end float (sideways movement) of the roller. If the roller is moving it will "absorb" the movement of the lever operated dog clutch making adjustment difficult/impossible.
The quick way to removed end float is to push the roller fully to the left (when reviewed from behind) and measure the gap between its right hand end and the right hand chassis side plate. Then remove the side plate and put the appropriate thickness of washers onto the roller shaft to eliminate the end float.
The better way to do it is to dismantle the clutch, remove the roller and insert the spacing washer at the left hand end of its shaft. Once the end float has been eliminated it should be easier to set up the dog clutch.
You may also find it easier to disengage the clutch if you carefully bend the lever upwards so that the top part is nearer to parallel with the lower part instead of pointing backwards as in your image.