Hydraulic run Log Splitter Question

[Ari]

My Dad's Kubota B 20 has an old 18" cylinder, 3000 psi log splitter. It has been leaking oil when used, now after sitting over 1 year I am trying to see why it's leaking. He told me the O ring has been replaced. I dumped the old oil out of it and I need to know if I have to fill it manually or let the tractors hydraulic oil fill it automatically.
Thanks

 

[J_J]

It will purge the air faster if you fill the cyl. In general, all cyl are self purging.