1980 L185DT Hydraulic issues

[DavidSO]

Hello all,

Tractor novice here. I grew up around ancient gas Fords but rarely did more than using and the simplest maintenance. Hydraulics were limited to the 3pt which never had issues.

Now I'm running into hydraulic issues with our 1980(?) Kubota L185DT. It has the L1700 loader.

1) One of the loader's lift cylinders leaks/drools where the rod exits the cylinder head. While I'd love to DIY, time constraints have me trying to find a competent shop. The other cylinder seems fine. Do I have both done at once anyway?

2) Both loader control valves leak slowly out the front of the spools. Diagrams show o-rings just inside. Simple fix? Buying a Summit unit is on the table but I think I'd need gauges and such to set the relief valves, no? If I go with a replacement, do you find unifying both spools to a joystick easier/faster? This two-stick was my first loader.

3) The bucket release/down action is weak. It will drop quickly when emptying a full bucket, but when I try to roll it further vertical to get out the loose bits it'll stop for several seconds like air is in the system. It still does this after I top off fluid and cycle both circuits several times, yet I don't detect mechanical resistance or binding; it just flops around. Really sounding like air but looking for perspective.

 

[TheOldHokie]

Hello all,

Tractor novice here. I grew up around ancient gas Fords but rarely did more than using and the simplest maintenance. Hydraulics were limited to the 3pt which never had issues.

Now I'm running into hydraulic issues with our 1980(?) Kubota L185DT. It has the L1700 loader.

1) One of the loader's lift cylinders leaks/drools where the rod exits the cylinder head. While I'd love to DIY, time constraints have me trying to find a competent shop. The other cylinder seems fine. Do I have both done at once anyway?
View attachment 156302 View attachment 156303

2) Both loader control valves leak slowly out the front of the spools. Diagrams show o-rings just inside. Simple fix? Buying a Summit unit is on the table but I think I'd need gauges and such to set the relief valves, no? If I go with a replacement, do you find unifying both spools to a joystick easier/faster? This two-stick was my first loader.

View attachment 156299

3) The bucket release/down action is weak. It will drop quickly when emptying a full bucket, but when I try to roll it further vertical to get out the loose bits it'll stop for several seconds like air is in the system. It still does this after I top off fluid and cycle both circuits several times, yet I don't detect mechanical resistance or binding; it just flops around. Really sounding like air but looking for perspective.

Welcome to the world of worn oit hydraulics
Does this loader have its own pump or does it use the tractord hydraulic system?

1. Wise Man say if it aint broke dont fix it.
2. I dont know what a seal kit costs or if its even availavle but replacng the stem seals is not a big job. If you are contemplating replacing the valve just forget the seals. No need to adjust pressure on a new loader valve but a gauge is only $20 and well worth having in your tool chest. Joystick with float on the lift circuit hands down.
3. Sounds like one or both bucket cylinders may have bad piston seals. If you roll a loaded bucket back to the stops does it hold or does it drift down? If it drifts how fast?

Dan

 

[DavidSO]

Welcome to the world of worn oit hydraulics
Does this loader have its own pump or does it use the tractord hydraulic system?

The loader uses the tractor's pump, rated at 6.2gpm @2300rpm new. I'm usually puttering around 1500rpm so the pace isn't swift in the best of circumstances. Air in the system has me stabbing at the foot throttle.

I'll leave the non-leaking cylinder alone then, so it can bite me next month. :/

On pressure adjustment, I was under the impression control relief valves should be tuned to protect a particular tractor/implement combo based on their specs? Bad impression?

Nothing on this tractor drifts, at all. I was surprised. Every time I've been absent minded and left something up, it remained there until I returned. Includes the bucket with gravel and a 500lb finish mower on the 3pt for a week. Haven't actually measured for movement - it's always accidental - but it's as if they lock in place until I hit one of the valves.

Thanks for your help on this.

 

[TheOldHokie]

The following discudsion of pressure settings assumes you are usimg the factory style hydraulic outlet block on thr left side of the hydraulic cylinder cover.

In that case the maximum.pressure is determined by the internal relief valve in the tractor housing. On the L185 that specification is 1900 to 2100 PSI.

The relief in the loader valve cannot imcrease that. All it can do is lower it. So yes, if the loader valve is set below the tractor it would need to be bumped up. While thats possible its not likely since most of these valves are good to 3000 plus PSI. It does not matter if its set higher.

If you dont know the factory setting of the new vakve and want to double check pressures when installing a new loader valve first connect a 3000 PSI gauge to the pressure supply hose coming to the new valve. If its low the pump is weak or the tractor relief setting is already low and needs to be adjusted.

If the tractor relief pressure setting is OK connect the pressure supply hose to the new valve and move the gauge to the power beyond port on the valve. If that pressure is lower than the tractor supply (inlet) pressure crank up the loader valve relief enough to bring the outlet pressure up to tractor side pressure. It does not matter if you overshoot on the adjustment because the tractor side is in control.

That entire process should take no more than 2-3 minutes and all you need is a $20 gauge and a couple $3 hydraulic fittings.

Dan

 

[Russell King]

@TheOldHokie
I don’t think an L185 has a pressure relief valve except in the 3point hitch. These are the ones with the block in the pressure line from the pump that you and Torch made the adapter block for.

On mine there is nothing but pump and pipe, no type of relief valve.

So that means the valve has to have a pressure relief in it as I understand it.

Added on edit: The pressure relief is in the 3 point control valve but does protect the pump- see below posts for clearer information.

 

[TheOldHokie]

@TheOldHokie
I don’t think an L185 has a pressure relief valve except in the 3point hitch. These are the ones with the block in the pressure line from the pump that you and Torch made the adapter block for.

On mine there is nothing but pump and pipe, no type of relief valve.

So that means thle valve has to have a pressure relief in it as I understand it.

I dont know what you have but the hydrauluc outlet block goes on the left rear of a L185 tractor and is AFTER the internal pressure relief. Picture of an L185 below. You could use a loader valve without a relief if you wanted.

Dan

 

[TheOldHokie]

I dont know what you have but the hydrauluc outlet block goes on the left rear of a L185 tractor and is AFTER the internal pressure relief. Picture of an L185 below. You could use a loader valve without a relief if you wanted.

Dan

View attachment 156353

I just today mailed a block to a guy with a L185. It replaces cap number 53 in this parts diagram.

Dan

 

[Russell King]

That is interesting indeed! My valve does not have that attachment cover. It looks like this

The block is in the tube as it crosses over the tractor underneath the seat, you can see your universal port block prototype installed in this picture.

But I was incorrectly thinking of the flow path only! I now see that is all really a pressure vessel with ports (now includes the rear remote hoses and valve) that has the pressure relief valve (Kubota calls it a dumping valve) in one of the ports so it is ”pressure connected” back to the pump even though it is way farther in the flow path. I was incorrectly thinking it needed to be early in the flow path to protect the pump.

In the parts diagram you posted, my arrangement is shown in the upper right hand portion of that page and I had never thought about that cover being the adapter mounting position. I thought that either it was like mine or did not have a place to attach the adapter plate.

So good for me, I learned something today (actually two things)! Thank you.

 

[TheOldHokie]

That is interesting indeed! My valve does not have that attachment cover. It looks like this
View attachment 156360

The block is in the tube as it crosses over the tractor underneath the seat, you can see your universal port block prototype installed in this picture.
View attachment 156361
But I was incorrectly thinking of the flow path only! I now see that is all really a pressure vessel with ports (now includes the rear remote hoses and valve) that has the pressure relief valve (Kubota calls it a dumping valve) in one of the ports so it is ”pressure connected” back to the pump even though it is way farther in the flow path. I was incorrectly thinking it needed to be early in the flow path to protect the pump.

In the parts diagram you posted, my arrangement is shown in the upper right hand portion of that page and I had never thought about that cover being the adapter mounting position. I thought that either it was like mine or did not have a place to attach the adapter plate.

So good for me, I learned something today (actually two things)! Thank you.

I am guessung you dont have PS.

Dan

 

[Russell King]

I am guessung you dont have PS.

Dan

No power steering and no FEL. Only hydraulics are rear remotes and 3PH.

 

[TheOldHokie]

No power steering and no FEL. Only hydraulics are rear remotes and 3PH.

Been a while since I looked at the WSM but I think the component missing from your tractor is the priority flow divider for ,PS.

Dan