Loader Adjusting the relief valve
- Thread starter mfuller
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Hooked_on_HP
Veteran Member
Which one. Loader or TPH.
Bill
Bill
jinman
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Mark, I'm very concerned about your adjusting the pressure on your hydraulic pump. If you are having decreased flow and speed on your backhoe, the pressure adjustment will do you no good. If you need more power, the higher pressure would help, but at the danger of blowing seals or the hydraulic pump seal and flooding your engine with fluid.
The very first thing you need to do is use that new port and check the pressure with a gage. Compare that pressure to the factory spec and determine if your pump pressure is low. I'm guessing your pressure is probably around 2200 psi, maybe even less. Does the manual you have show the spec'd pressure?
With all that said and warnings given, right in front of your right foot rest is a block where the loader's hydraulic lines attach. It's called the System Diverter Valve. On the bottom of that block is a large hex nut. Removing that nut will remove the pressure relief valve. You can order a shim kit to increase pressure by adding shims (about 150 psi per shim). PLEASE, PLEASE don't do this without knowing exactly what your current pressure is and if it needs increasing to meet the spec. That's the best advice I can give.
The very first thing you need to do is use that new port and check the pressure with a gage. Compare that pressure to the factory spec and determine if your pump pressure is low. I'm guessing your pressure is probably around 2200 psi, maybe even less. Does the manual you have show the spec'd pressure?
With all that said and warnings given, right in front of your right foot rest is a block where the loader's hydraulic lines attach. It's called the System Diverter Valve. On the bottom of that block is a large hex nut. Removing that nut will remove the pressure relief valve. You can order a shim kit to increase pressure by adding shims (about 150 psi per shim). PLEASE, PLEASE don't do this without knowing exactly what your current pressure is and if it needs increasing to meet the spec. That's the best advice I can give.
RickB
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Yes .
JC-jetro
Elite Member
Mark,
It seems your 1710 hyd is pretty close to my 1700. Take a look at the thread below and you'll find what you need. It is lengthy discussion, you might directly go to the 3rd page of the discussion although there is plenty of good info there.
I would not increase the pressure unless you're way below the specs.
JC,
http://www.tractorbynet.com/forums/new-holland-owning-operating/130597-adjust-not-adjust.html
Harry in Ky
Veteran Member
If you're asking for help and advise, you might start by describing the problem, and why you feel the need to adjust the relief in the first place. On most of the NH compacts the relief is one item that rarely needs adjustment.
Harry, here's my problem. I've got a 1710 with a 770B loader. The loader seems a little weak, It won't raise the front wheels off the ground unless you place it flat on the ground, then use the bucket dump to raise it (kinda cheating). Not sure if this is normal. I recently added a GB 651 backhoe that came with a self contained pump rated at 2250 psi. I removed the pump and reservoir and plumbed it directly into the tractor 3PH hydraulics. The hoe seems to be around 10% weaker, when running off the tractor hydraulics. Now, the tractor hydraulics are specd at 2133 psi. The loader is specd at 1600. I agree, I do need to check the system pressure before adjusting anything, but I didn't want to buy a pressure gauge if adjustment wasn't possible anyway. I have the loader manual and it shows an inline pressure relief valve, but I cannot find it on my setup. I wasn't sure if someone simply lowered the whole system pressure to accomplish this. JC, wonderful schematic on that post. Bill, I didn't realize there was another relief valve for the 3pt. I see that in JC's schematic. So, now that I know it is adjustable, I will pick up a gauge tomorrow. If it is below spec, I assume it will be cause the pump is worn. Is it normal to simply shim up the relief valve, or will the pump need repair?
JC-jetro
Elite Member
Mark,
if the pump is tired adding shims would only add to it's misery and it will blow a seal. a blown seal and tractor running will sure enough kill the pump. Your hyd system is live, your pump will turn even if you are not using any hydraulic driven implement or 3 point system. A gear type positive displacement pump will destroy itself in a short time without lubrication.
Buy a liq. filled gauge up to 5000 psi from Northern under $25. that's a great investment, see where your system relieves pressure at. That is your pressure. need to go a bit higher than the top notch and relief valve will start chattering. if your are less than I think 2133 psi ?? then by all means raise it some. don't need to have a shim here as you have adjustment screw under the relief device cap. You shim if you don't have the adjustment screw.
JC,
if the pump is tired adding shims would only add to it's misery and it will blow a seal. a blown seal and tractor running will sure enough kill the pump. Your hyd system is live, your pump will turn even if you are not using any hydraulic driven implement or 3 point system. A gear type positive displacement pump will destroy itself in a short time without lubrication.
Buy a liq. filled gauge up to 5000 psi from Northern under $25. that's a great investment, see where your system relieves pressure at. That is your pressure. need to go a bit higher than the top notch and relief valve will start chattering. if your are less than I think 2133 psi ?? then by all means raise it some. don't need to have a shim here as you have adjustment screw under the relief device cap. You shim if you don't have the adjustment screw.
JC,
Last edited:
jinman
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JC, are you talking about the valve circled in red on the photo below? I believe this valve has the output of the main hydraulic pump routed to it. It's the valve with the pressure relief on the bottom and has a shim kit listed in New Holland's parts list. If it is set at a low value, any relief valve after it will not be able to raise the pressure. It's possible that your tractor doesn't have this since I think these were not added until later in the model line.
