1998 NH 675E 900 hrs. Hydraulics seem slow compared to other hoes I have ran. Is that just how the machines are or do I have a clogged filter somewhere, or a bigger issue? I had to rebuild all the cylinders when I got the machine due to dried out seals, but I changed all the filters and put new hydr. oil in, after I got all the cylinders back. Any advice would be appreciated!
What did the oil look like when did your servicing? Honey brown, black, or milky? If the oil was honey brown, it's probably normal speed for that machine. You might try and lift the ass end with the hoe and see how much power it has. Seems like most of the time the power drops off before the speed when you have flow or pressure problems. What other machines did you run? Your NH is on the big side for a hoe, the bigger cylinders need more gpm of oil from the pump to move fast, my 750 sized Ford has really big cylinders so it's not fast moving like a 555. Ford hung a turbo on the later models just so they could increase the gpm out of the pump to move the bigger parts. Not being an operator with years of daily experience, slow and powerful works great for me; I'd do too much damage if this thing was fast too.
Oil was honey brown when I changed it, and it still is from what I can see in the sight glass. Machine has plenty of power; It'll lift itself no problem, and I push myself forward and back with the hoe no problem. I have a ran a JCB 217 for a short time, to borrow. Hated it. I used to run a 710J quite often, and I've been in a 410 and 310 on a few occasions, all seemed quicker.
Sounds OK, but if you compare the gpm from the pump and how big the cylinders are, you'll probably find the JD's have a little more gpm compared to the size of the cylinders. That's where the speed comes from. That and whatever size valves and hoses they picked to plumb the whole thing. Guy I bought my Ford from said they ran 36" buckets to compensate for the slower cycling of the hydraulics. But it had the power to run those big buckets and they got the production that way. Something you might try if you need to move a bunch of dirt.