1999 M120 Kubota 3pt lift lockout (2026 thread)

[TheOldHokie]

Ok when I blow compressed air at 120 psi is blows right back out the labeled port 3 in the pic

Lets be clear. You are blowing compressed air into port 3 and it does not pass through the valve?

Have you identified port 3 is pump inlet for the valve as shown in the schematic? You would do that by matching it to the pump port on the lift top cover.



What I am trying to do is identfy and test flow (red line) through the neutral circuit in the valve.

Dan

 

[Pmschmitt]

Ok here are the results of the compressed air test

air in 1- comes out 3
Air in 2 - goes no where
Air in 4- comes out 5 (small hole)
Air in 3- comes out 1 (small amount out 5)
Air in 5- comes out 4

see attached image with orientation in casting.

when I blew air from the rear remotes outlet ( when they were removed earlier) into the 3 pt the air came out of hole corresponding to #1 in the casing so I believe that is the first place the fluid goes

I will say that in the WSM for up and down control the picture is wrong as the larger bore spool is the upprimary and the smaller spool is the down spool. Green is associated with up lift blue is associated with down if that helps

 

[TheOldHokie]

Ok here are the results of the compressed air test

air in 1- comes out 3
Air in 2 - goes no where
Air in 4- comes out 5 (small hole)
Air in 3- comes out 1 (small amount out 5)
Air in 5- comes out 4

see attached image with orientation in casting.

when I blew air from the rear remotes outlet ( when they were removed earlier) into the 3 pt the air came out of hole corresponding to #1 in the casing so I believe that is the first place the fluid goes

I will say that in the WSM for up and down control the picture is wrong as the larger bore spool is the upprimary and the smaller spool is the down spool. Green is associated with up lift blue is associated with down if that helps

Slow down - air in 1 comes out 3 appears to be P and T1.

Remove the filter and blow air into T1 on the lift cover - it should come out the filter mount on the side of the c9ver. That is the circuit I highlighted in red on the schemstic.

Dan

 

[Pmschmitt]

yes compressed air blown into casing corresponding to hole 3 on the block enters the rear hydraulic filter

 

[TheOldHokie]

yes compressed air blown into casing corresponding to hole 3 on the block enters the rear hydraulic filter

OK - now thats pretty damn simple.

If port 1 goes to port 3 in the valve and port 3 then goes to the filter how can oil delivered to port 1 not enter the filter? Something is not right here.

Dan

 

[Pmschmitt]

I agree. Doesn't make sense. When I just did this test filter was still dry.

 

[Pmschmitt]

Do I need to borrow a buddies bore scope

 

[TheOldHokie]

1

I agree. Doesn't make sense. When I just did this test filter was still dry.

You do not need a borescope. You need more testing. I want to see oil coming out of port 1 on the top cover. Can you crank the engine without starting it?

Dan

 

[Pmschmitt]

I think I could crank it with the pull stop pulled out to prevent fuel from entering and prevent a full start. I will attempt that after work tomorrow. Thanks again for the help.

 

[TheOldHokie]

I think I could crank it with the pull stop pulled out to prevent fuel from entering and prevent a full start. I will attempt that after work tomorrow. Thanks again for the help.

No problem - this system interests me.

When you crank the engine you want to identify where oil exits the top cover if at all.

Dan

 

[Pmschmitt]

Understood I'll report back after this test

 

[Pmschmitt]

Ok cranked tractor over for about 15 seconds with the emergency stop pulled so it would not start. No oil coming out of any hole in the casing.

 

[Pmschmitt]

There is oil in the casing but none coming up or filling when cranked. I repeated test twice and same results, but when tractor was running with block on each time I removed it there was oil present.

I am assuming this means rear remote block is the next up stream possibility of the problem. I have already removed once but can take apart again.

 

[TheOldHokie]

There is oil in the casing but none coming up or filling when cranked. I repeated test twice and same results, but when tractor was running with block on each time I removed it there was oil present.

I am assuming this means rear remote block is the next up stream possibility of the problem. I have already removed once but can take apart again.

Just to be clear - when cranking the tractor there is no oil coming from any port in the hydraulic cover? If so start the trsctor and observe what happens. Be prepared to shut it off quickly should oil spurt.

If there is no oil coming fron the cover the next thing to check is that ALL remote spools are in neutral. You can do that without taking anything apart.

You have said the remotes work - how did you verify that?

Dan

 

[Pmschmitt]

started tractor oil coming up through casing that corresponds to hole 1 on block that we established is the P or pump.

Verification of rear remotes
remotes are in neutral
Remotes would lug tractor when going up or down and could feel change in lines

Again when tractor is running hydraulic fluid present at corresponding hole 1

 

[TheOldHokie]

started tractor oil coming up through casing that corresponds to hole 1 on block that we established is the P or pump.

Verification of rear remotes
remotes are in neutral
Remotes would lug tractor when going up or down and could feel change in lines

Again when tractor is running hydraulic fluid present at corresponding hole 1

How much flow are you getting with the tractor running - a dribble or enough to make a real mess?

Are you operating the remotes without anything connected to the outlets?

Do you have a loader on this tractor?

Dan

 

[Pmschmitt]

I am getting flow approx 2 inch column of hydraulic fluid above casing not a dribble

Yes loader, loader lifts tractor off the ground and is strong.

have not hooked implement to rear remotes as I just purchased and dug into the 3pt problem

 

[TheOldHokie]

I am getting flow approx 2 inch column of hydraulic fluid above casing not a dribble

Yes loader, loader lifts tractor off the ground and is strong.

have not hooked implement to rear remotes as I just purchased and dug into the 3pt problem

What model loader?
Hook a hose to one of remotes and check how much flow you get pumping into a bucket

 

[TheOldHokie]

I am getting flow approx 2 inch column of hydraulic fluid above casing not a dribble

How can you be getting that volume out of port 1 with nothing going into the filter (port 3)?

Dan

 

[Pmschmitt]

Yes I agree makes no sense. It is a la1301 loader. I will have to re assemble 3pt block to check rear remote flow.

on a side note I purchased a used complete 3pt dist block off eBay and it arrived today. Unknown if it worked but have a 30d return warranty if not working or not what is needed.