I have a Massey 1526 tractor. When using the bucket tilt or when lifting the 3pt hitch I hear fluid going through the loader relief valve. I hooked a gauge into the loader bucket tilt port and it bypasses at 1600 psi? Is this normal? The tractor manual says the pump puts out 2130 psi. The manual for the loader says operating press is tractor press which is 2130.
Loader relief valve
- Thread starter Bhenders
- Start date
- Views: 1438
rScotty
Super Member
- Joined
- Apr 21, 2001
- Messages
- 9,554
- Location
- Rural mountains - Colorado
- Tractor
- Kubota M59, JD530, JD310SG. Restoring Yanmar YM165D
Congratulations on getting some diagnostic information with the pressure gauge. If you have or can make up a "T" fitting with the right fittings, it is convenient to just leave a psi guage in line there where you can see it. I have one on the input to my loader valve & it's been there for years. It gives me a sense of the hydraulic system health as well as how much of a load I have in the loader.
It does sound like that relief valve is actuating too soon. This might be a good time to disassemble the relief valve and see what is going on. They are pretty simple. All relief valves adjust by varying how much spring force it takes to keep the relief valve shut. Some preload the spring with a threaded adjustment and some with shims. Keep any shims clean and everything in order.
good luck,
rScotty
It does sound like that relief valve is actuating too soon. This might be a good time to disassemble the relief valve and see what is going on. They are pretty simple. All relief valves adjust by varying how much spring force it takes to keep the relief valve shut. Some preload the spring with a threaded adjustment and some with shims. Keep any shims clean and everything in order.
good luck,
rScotty
ericm979
Super Member
- Joined
- Nov 25, 2016
- Messages
- 5,813
- Location
- Santa Cruz Mountains CA, Southern OR
- Tractor
- Branson 3725H Deere 5105
If it's opening the relief with nothing in the bucket or on the 3pt and they are not at the end of their travel, something is wrong.
I failed to mention I have a 60” box blade on the 3pt and bucket full of snow.
Thanks I have taken the relief valve out and cleaned it. I did not take it apart. When I was at the dealer we looked up a new relief valve in the parts book and it didn’t show any shims or adjustments. I could buy a new one but would like to know for sure that this is the problem. New one is $160.00. Installing a gauge sounds like a good idea I will look into that Thanks.
rScotty
Super Member
- Joined
- Apr 21, 2001
- Messages
- 9,554
- Location
- Rural mountains - Colorado
- Tractor
- Kubota M59, JD530, JD310SG. Restoring Yanmar YM165D
When you take the end off the relief valve I bet you will find how it adjusts. If you do that and didn't find some shims, it's because there is anadjustment screw instead. The 1600 psi you saw sounds suspiciously like the default setting on a standard relief valve. If everything else is working OK my guess is that the tractor mfg. forgot to set the default relief valve pressure for normal tractor operation.
Does one end of the relief valve have a threaded cap you can remove? Usually the adjustment screw is under that. Put a pressure gauge into the port, take off that end cap, and adjust the screw.
You can make up a handy pressure gauge for yourself. It will cost $100 or so for parts. If your junk box doesn't run to hydraulic fittings, get some new "T" or "Cross" fittings plus the necessary adapters for whatever type of thread your loader control valve uses. If your loader hoses have quick detachable fittings for removing the FEL, you can equip your pressure gauge with those, too. That makes it even easier.
The gauges themselves are often cheaper than the fittings.
I like to buy US or known brand fittings rated at about twice the pressure I expect to see. One good source is: Hydraulic Adapters & Fittings | Hydraulics | www.surpluscenter.com
Look around while you are at that site. They also sell prince brand 1850 universal relief valves in 1/2"NPT adjustable from 1000 to 2500 psi. $60.00. If your relief valve was completely shot You could plumb one of those into your existing loader control valve... but try adjusting yours first.
For about $200/300 you can even buy a good USA-built complete loader control valve and it will come with float, power beyond, and a relief valve built in. But you will still have to adjust the relief valve. It takes about 5 miutes, but the adjustment does require a gauge.
good luck,
rScotty
Thanks your awesome!
