3-Point Hitch 1500D 3 point hitch control valve?

[Onthesauk]

I recently changed the hydraulic fluid and cleaned the filter on my 1500D. I used it one time since then for a couple of hours to till the garden and everything worked fine. Today I used in for half an hour and when I put it away, the 3 point hitch wouldn't go down. Appears the pin on the back of the hydraulic control valve free floats.

Entire assembly is available from a dealer but quite expensive. Wondering if there is any other alternative, i.e. dismantle and clean?

 

[JC-jetro]

I recently changed the hydraulic fluid and cleaned the filter on my 1500D. I used it one time since then for a couple of hours to till the garden and everything worked fine. Today I used in for half an hour and when I put it away, the 3 point hitch wouldn't go down. Appears the pin on the back of the hydraulic control valve free floats.

Entire assembly is available from a dealer but quite expensive. Wondering if there is any other alternative, i.e. dismantle and clean?

"Appears the pin on the back of the hydraulic control valve free floats." can you explain that a bit. The spool valve is open centered so after 3 points achieved it's required height then the feed back linkage on the lift arm should cause the valve to go to the center by spring action hence directing the flow back to the reservoir. Is this what you are referring to?

Do you have rate of return knob (needle valve) below your seat. It may be that the needle valve is fouled by some contaminant and not allowing the full lift piston to drain the hyd oil back to the reservoir. I clean that first before disassembling and cleaning the spool valve. spool valve has many little sealing o-rings and seal easily to be dorked up.

JC,

 

[Onthesauk]

Yes, no spring action on that pin.

And yes, saw all the o-rings. Probably explains why they sell it as an assembly rather then the individual parts.

I've got the return knob, but haven't looked to see how that comes apart.

 

[1danny]

Yes, no spring action on that pin.

And yes, saw all the o-rings. Probably explains why they sell it as an assembly rather then the individual parts.

I've got the return knob, but haven't looked to see how that comes apart.

Most of the individual parts are available too.

Danny

 

[Onthesauk]

JC-jetro

On the diagram there is a stop valve behind the return knob. Is that what you're talking about?

Thanks

 

[JC-jetro]

JC-jetro

On the diagram there is a stop valve behind the return knob. Is that what you're talking about?

Thanks

I may be able to help you if I see the diagram. Do You mean check valve when you say "stop valve". There should not be a check valve(allows flow in one direction only by spring action and ball or some other design) in the inlet pipe or passageway to the lift cylinder since the flow needs to go back to the reservoir in order to drop the lift arm. On some like my Ford 1700 there is a check valve after rate of drop needle valve to take care of shock load to the lift cylinder seal. Let say you have something heavy on your three point and hit a bad bump causing shock loading to the lift arm that is transmitted by hyd oil to the lift system component. this check valve dumps a bit of the oil to compensate the shock loading. A diagram can really help. Meanwhile did you turn the knob CCW (left , counter clock wise) to see if the arm drops?

Jc,

 

[Onthesauk]

Yep, knob has always been turnied all the way out. Turned it in and back out a couple of times with no effect.

 

[JC-jetro]

Yep, knob has always been turnied all the way out. Turned it in and back out a couple of times with no effect.

That kind of leads to spool valve as the culprit. Between discharge of the spool valve and inlet to the lift cylinder should be nothing else other than rate of drop needle valve. Before I take my spool valve apart I'll loosen the the lift cylinder head. I do not take the head completely off... just enough to relive the trapped oil to see if the arms come down. weight of the arm alone or with some implement should provide enough down force to move the lift arm. if it does not There may be some mechanical binding and not hydraulic. On my Ford the head has o-ring against the lift housing. what I propose may get a bit messy. by the way some lift systems are different and the whole top has to come off before you have access to the lift piston below the housing,. is yours close to what I had in the pics?

By loosening the head a bit you'll bleed pressure from lift cylinder.

Picture of the spool valve in the lift housing.

 

[Onthesauk]

JC-jetro,

Thanks for all the time you've spent responding and the great pictures! I've pretty much got the yard put to bed for the Winter, can get by without the tractor. Think I'd better order a manual and start tearing it down. Also have a neighbor down the street who has rebuilt a few tractors, hopefully can draft him if I get stuck.

Thanks again!

 

[JC-jetro]

JC-jetro,

Thanks for all the time you've spent responding and the great pictures! I've pretty much got the yard put to bed for the Winter, can get by without the tractor. Think I'd better order a manual and start tearing it down. Also have a neighbor down the street who has rebuilt a few tractors, hopefully can draft him if I get stuck.

Thanks again!

My pleasure, good luck and let me know if I can shed some help.

JC,