Quote Originally Posted by nhengineer View Post
I'm curious what GOOGLE thinks a "big MF pipe wrench" is.
It thinks it is a pipe wrench, to me they have always been called Stillsons.

Quote Originally Posted by nhengineer View Post
Does the ram creep back under load? That would most likely be the check valve. I'm glad to share what I know with you.
Maybe you misunderstood my original post. I have no problem with the main piston seal nor creep. Certainly not since I honed the cylinder. There was a leak from the ram wiper O-ring seal which made a mess because the jack is mounted upside down and so the whole of the reservoir oil and the header tank was acting on it. It couldn't have happened with a right way up jack.

Anyway I have now removed the outer cover and I feed and drain directly into a low mounted reservoir, so if anything leaks the maximum quantity is only the tiny amount in the O-ring groove above the O-ring, only a couple of ml at most. I'll make a separate post describing the current configuration.

Many thanks for your willingness to help.

BTW where do you live in NH? I lived there for 3 years, 2008-2010. I lived in New Boston and worked in Bedford.