Two hydraulic problems

[Digger_Bear]

I don't have this problem with my Magom pump. Been running it for over an hour today scraping some weeds out of the garden, even stalled the pistons on some occasions but no excessive heat problems.

It does sound where your oil is shared between a pair of pistons there isn't enough pressure left to work them as well as the singular ones. On my excavator the main boom pistons which work in a pair are split at the valve block then piped separately so at a guess maybe your pipes cannot carry enough volume to the pair of pistons, might also explain why the pump is getting hot if it's struggling to force enough oil.

[Supermario]

Try and test the 2 cylinders one at a time. When 2 cylinders share the same supply , if one is bad, both will be weak.or maybe there's an issue with the valve?
Perhaps your running the motor too fast? Have you tried reducing pump speed and see if temps drop? I would deal with cylinder issue first then take a closer look at heat issue.