Yes and no.
Capacity on a dual acting valve can be overcome by adding oil till it's full on one side. the refilling the hyd resevoir.
psi likely won't be the main problem.. but gpm will
naa should max out at about 2.9gpm at 2000 engine rpm. I run a loader on my NAA and it's a hair slow.. but i get by with it.
I -HAVE- seen people use 9n,2n,8n, and NAA on splitters using the belly pumps ( 9-2-8N ) or engine side pumps ( naa ).. both being 2.9gpm.
It's darn slow.. but works....
Here's the hitch.. to get fluid pressure out that pipe plug on the small blank plate on the top cover you need to chain your upper 3pt lift arms to the axle trumpets.. then remove that plug, and plumb a hose into there. use that hose to feed your DA open center log splitter valve input port. the splitter valve will also have a return line, you will need to return that oil to the sump. Most people remove the hyd fill cap and drill / tap the cap for a fitting and plumb the line there. Now.. you lift the 3pt handle up.. the 3pt can't move cuz you chained it down, and now oil goes out that port to your open center valve, and circulates back tot he sump via your return to fill port. Once you operate one of the controls to split or retract, that oil is then diverted to the cyl to do the dirty work... you will want your machine at rpm to do any meaningfull work.
Now.. that said.. there are some dirty lil mods you can do to get around some of that hassle of chaining the lift arms down. you can remove that lil plate, plug one port, then drill another port on it.. repalce the cover, then remove a inverted hex plug from the lower center housing above the relief valve and pickup pressurized oil there, run this line to a da open cener valve, and it return to that new port in the top plate... run the da valve to a set of QD's and you have just made yourself a DA remote and don't even have to chain the lift arms down as you pickup oil before the 3pt gets it. The hitch is that that lil cover is cast.. and pretty much NON REPLACEABLE.. and you are doing milling drilling and plugging on it.. and ya get one try to do it right or your naa don't work!
I've been using the chain-down arms thing for a while and have now just finally did the hyds mod that will let me use a da valve I'd had in my shop for a few months collecting dust. I was unwilling to modify and chance ruining my top cover blank plate so I've been looking for a better part of a year and FINALLY found one on a salvaged tractor and had a frined who is a machinist do the drill/tap/plug/redrill/tap job on it. I should have mine inthe mail any day, and then I will have live loader and 3pt hyds back again.
Your other options are to get a front hydro pump.. or a rear pto pump.. both would require a sump tank and a relief valve.. personally I'd choose the pto pump foe easy of plumbing vs a front pump.. unless I had a loader as well.
the chain and tap method will by far be the easiest and slowest.
all depends on how much wood you want to split.. and how fast.
if this is just a hobby deal and you want to set around and drink some adult beverages and shoot the breeze while casually splitting the wood.. then the naa will do it with onboard hyds.. but it just won't get in any hurry for ya!.
if this were a newer 00/01 series it would have a 4gpm pump, and there are easy to find valves that bolt right on the top cover.. tisco still makes them.. new single units are about 400$ and new duals are about 800.. you can find used ones in the 150-300$ range.. but again.. only fit 55+ units.
There were rare NAA hyd top cover valves available.. but are now like hens teeth..
soundguy
