Ford/NH 2120 Hydraulic troubleshooting

[CJFONNER]

Troubleshooting main/loader hydraulics on 2120. Pressure should be around 2500. Did pressure test with gauge and pressure shoots up to about 2000 for a second, and then settles down to 1200 after 2-3 seconds. What would cause this? Weak pump, or internal leak in one of the cylinders or in the spool valve? …or does the relief valve need shimming?

Any help or guidance is appreciated.

 

[TractorTech]

How are you performing the pressure test?

 

[Harry in Ky]

And WHERE on the tractor is your gauge plumbed in? Explain a little about what you have for a loader valve, and does it have three lines connected to the square diverter block on the right side of the tractor?

 

[CJFONNER]

Yeah...sorry for the vague post, guys. The tractor is a 1991 Ford 2120, with the 7109 loader. It has a Diesel Kiki double spool valve. I was testing with a 5000psi gauge plumbed into the loader boom lift line via a quick connect at the front of the tractor, which has 4 quick connects that feed the loader cylinders.

I have since done a bit more troubleshooting and narrowed the issue down to the spool valve for boom lift and lower functions. The curl/dump spool valve reads 2500 psi and holds as it should.

On the suspect spool valve I think I'm getting some fluid leaking internally between the lift/center/lower cutaways, which is leading to the rapid bleed off of pressure when the lever is held in position.

I'm going to clean and reassemble the spool to see if it repairs itself, but before I do are there any telltale visual signs that would indicate internal leakage like I describe above? FYI, the valve is bone dry on the outside.

 

[TractorTech]

Yeah...sorry for the vague post, guys. The tractor is a 1991 Ford 2120, with the 7109 loader. It has a Diesel Kiki double spool valve. I was testing with a 5000psi gauge plumbed into the loader boom lift line via a quick connect at the front of the tractor, which has 4 quick connects that feed the loader cylinders.

I have since done a bit more troubleshooting and narrowed the issue down to the spool valve for boom lift and lower functions. The curl/dump spool valve reads 2500 psi and holds as it should.

On the suspect spool valve I think I'm getting some fluid leaking internally between the lift/center/lower cutaways, which is leading to the rapid bleed off of pressure when the lever is held in position.

I'm going to clean and reassemble the spool to see if it repairs itself, but before I do are there any telltale visual signs that would indicate internal leakage like I describe above? FYI, the valve is bone dry on the outside.

No visual signs and not any repairs that you can do, including removing and cleaning. A leak internally would mean the valve has to be replaced.

 

[CJFONNER]

Thanks TractorTech. That’s kind of what I figured.

I looked at a bunch of different joystick loader valves online - lots available in the $100-300 range. They all seemed about the same, but they all had the power beyond port in the side which won’t work due to the limited space between the sheet metal and loader frame.

I ended up finding and ordering one from Prince, in their LVT Series, which looks like it will be a direct drop in replacement.

In case anyone else finds themself in this scenario here is a link.

Prince LVT