1020 hydraulic problem

Early 1020 model, 37 model loader, losing hydraulics on loader and 3pt, changed filter, fluid, cleaned sump screen on both pumps. Works fine 60% of the time then stops working for 30 seconds or so, then pump begins to pick back up, might work another hour might work 5 minutes.

You don't have the clutch in when using the loader do you? Transmission pump only feeds the reservoir above the hydraulic pump when the transmission is spinning.

No. It doesn't make a difference if clutch is pushed in or not.

(quoted from post at 17:48:20 03/25/23) Early 1020 model, 37 model loader, losing hydraulics on loader and 3pt, changed filter, fluid, cleaned sump screen on both pumps. Works fine 60% of the time then stops working for 30 seconds or so, then pump begins to pick back up, might work another hour might work 5 minutes.

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Loader hydraulics connected to the SCV ? Or direct to the high pressure line that supplies the SCV . With the oil returned to a ported filter cover ?
Otherwise the oil cooler and front tank will run empty which will make the front pump starve .

Is there a vent somewhere in the reservoir system?

Connected straight to the SCV.

I have no idea. There is a small reservoir up front but I dont know about a vent. What would it look like?

(quoted from post at 22:30:39 03/25/23) Connected straight to the SCV.

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Well there is the problem . It will NEVER operate properly when connected to the SCV .
The SCV were designed for a lift cylinder on a cultivator . Not for high volume loads .

(quoted from post at 21:51:21 03/25/23) Is there a vent somewhere in the reservoir system?

Click to expand...

Hyd reservoir(trans case) has vent in cap that covers opening behind seat where hyd oil is added when required. Is loader controlled by scv or ind valve attached to scv?

Below is a schematic that depicts best method for operating a frt end loader on a JD utility tractor such as a 1020.

Hmmm, ok then. How do I connect it
properly?

Where did you pull the schematic from?
Can you provide a link please?

JDparts.com
Connect for pressure at green T

https://partscatalog.deere.com/jdrc/sidebyside/equipment/77968/referrer/navigation/pgId/64029837



This post was edited by Tx Jim on 03/26/2023 at 07:21 am.

I dont see the part number for the filter
cover. I assume Deere made a special
ported filter cover. I'll look further
in online catalogs but I'm having
difficulty finding it so far. Thanks for
your help.

JD had 2 different ported filter covers. L55982 @ $126.42 or T31170 @ $483.94 . Either cover will fit your tractor. Cheaper cover is lighter in construction but should be fine

This post was edited by Tx Jim on 03/26/2023 at 09:29 am.

My 1020 has the same loader on connected to the scv since new in 1966. If the clutch is being used lot when using the loader, it will loose hydraulic pressure because of the reasons described above. Transmission pump won't keep up with hydraulic flow for loader with clutch pushed in but works fine otherwise. So this hydraulic filter cover you would route all the return oil from the scv back to the filter instead of back into the rockshaft housing which it does normally, correct? This would stop my starvation issue for the main hydraulic pump, correct?. Thanks for your help too! I'd like not to have this issue. I replaced the both the transmission and hydraulic pump about 5 years ago but have only put about 60 hours on it since then. I know they have this issue and run the tractor accordingly to help alleviate this issue.

Your will be amazed at how much faster the loader
Hydraulics operate and with less noise . When connected to a direct supply and returned via a ported filter cover .

mkuhns,

The SCV return oil remains as it is, the return oil from the loader's control valve is returned to the ported cover. A dedicated supply line for the loader valve is teed in to the pressure line between the pressure regulating valve and the SCV. Does your loader have its own control valve or are you using the SCV to supply or operate the loader function(s)?

Thanks man, really appreciate it!

It is connected to the SCV now. Another
poster suggested I not connect it to the
SCV but instead run to the port on the
side of the paper filter cover.

My post was replying to mkuhns question, however from reading through your posts a review your current loader hook up may be in order to clarify things. A complete description of what your loader and plumbing is may help clear this up. Does your 37 loader have single acting lift cylinders? Do you have a hydraulic bucket with double acting bucket cylinders, or a trip bucket (no cylinders)?

Does your loader have its own control valve?

You posted the loader is connected direct to the SCV. Do you use the SCV lever(s) to work your loader function(s) through hose(s) from the remote couplings at the rear of your tractor, or does the SCV lock in to supply the oil to a loader mounted control valve and accept the return oil from said loader valve through hoses attached to the remote couplers? If you have single acting cylinders using one hose from one remote coupler, lifting and lowering controlled by the one SCV, that one hose is both supply and return, so using the ported filter cover would not apply. Unless you install a loader control valve, plumb it separate supply and return hoses, and stop using the SCV and remote couplers.

What has been suggested to you (and mkuhns) is that for best operation of a loader the oil supply should come from a tee, in the pressure line ahead of the SCV, to a loader mounted control valve. Then the return oil from that loader control valve should be returned to the ported transmission filter cover. This is what is shown in the parts drawings Tx Jim posted for you. This plumbing arrangement eliminates using the SCV(s) and remote couplers. The parts catalog also shows one hose from one remote coupler, controlled by the SCV, to the single acting lift cylinders, for a loader without bucket cylinders.

If a loader mounted control valve is used it must match the type of system. Your 1020 is a closed center system so the loader control valve must be for a closed center system. (And single acting cylinders work better if a double acting valve is not used.)

If I'm wrong, hopefully TX Jim, buickanddeere, or someone will correct my errors.