I have a NH EC25 excavator which has recently developed a leak in the valve body that attaches to the top of the slew motor. The leak is coming from one of the spring-loaded check valve plugs that control return flow back to the tank. I thought it was the O-Ring, so I changed that as well as the plastic backing ring. However, it still drips steadily and makes a mess. I suspect that this plug may have a tiny crack in it although I can't visually detect it. There is an internal oil journal in the plug itself. I went to my New Holland dealer and they don't list this small plug as a repairable item. Instead, they offered me the entire valve block assembly complete with cartridges for a whopping $1800. I told them they were insane. They are looking into this issue to see if they can obtain the valve plug only, but I'm not holding my breath. In the meantime, does anyone have some ideas as to how to fix this leak? I'm considering throwing some liquid gasket around the plug and then screwing it back in. I'm hoping it will seal where the hex head mates to the surface of the valve block. If I could find a used parts dealer or wrecker, maybe they would have the plug. Failing that, I'm going to have a look at the valve body to see who made it and try and source the part that way. This is a relatively small problem, but annoying nonetheless. I find that New Holland's parts prices are often outrageous. BTW, I'm located in Manitoba, Canada.
Is there any way you can post some pics? Kinda hard for us to know what we're working with.
Is this the valve that is leaking? I think I pointed to the relief instead of the plug. If it leaks from the plug I would suspect a crack in the valve block not the plug. Seen a couple plugs leak but usually it's a crack in the valve casting.
That's exactly the right spot. Thanks for posting the picture. It is leaking around the plug. I also thought of a cracked valve block. I'll probably have to pull the whole thing off and try to see if I can find the crack. Thanks for the advice.
I checked out the online pricing on the valve body itself. It's listed as unavailable. Ugh.
Does anyone know of a source for used excavator parts in North America?
I pulled the aluminum valve block off the machine today. There is a crack running between the check plug and the relief valve. I will see if I can find a local hydraulic shop that carries the valve block.
That valve may just be a standard cross over relief valve. A local hydraulic supplier may be able to find one for you. You might try schaefer equipment for a used part. The can be found on the web at www.sewlparts.com They ship to Canada and we have found their prices very good and the quality of parts excellent. I know they deal a lot with Case, Cat, Bobcat, Kobelco not sure how much New Holland they see.
Just heard back from the OEM distributor who makes the valve block for New Holland. It turns out that New Holland has a proprietary agreement with them such that they cannot sell those blocks to anyone but New Holland. How nice of them.
Sorry to say but proprietary parts are common in this business. It stops another company from hijacking machine design.
Just an update on my issue with the crossover relief valve. I stopped in at Princess Auto the other day and found a crossover relief valve on sale for $60. I picked up a couple of inline check valves to deal with the anti-cavitation check feature. I'm going to get a local machinist to make me an adaptor plate to mount the new valve on the motor. Due to space limitations, I will have to mount the check valves on the side of operator's seat, but aside from that I will likely be spending less than $500 on the total repair.
Another update. I talked to my local machinist and he is going to clone the existing valve block for around $400. He has the cutters and taps to do it. Now everything will still fit in the existing space.