lower it you go to the bottom of the stroke where you then push the handle harder to overcome a strong spring to move the jacking pump into the lowering position.
Almost right, but its pull not push!
Was about to temporarily give up on it when I put my foot on the base, pulled the handle right it out and down it went under the action of the two retractor springs. Quite a stretch with no load to hold it in place.
Have subsequently found this website that is packed with information about just about every jack made but not, it appears, this one. I’ll keep you posted.
https://mgaroadster.co.uk/index.htm