Replaced all loader hoses and can only get minimal function

Nickk

Member

Equipment
L3600 Kubota
Jan 24, 2023
73
8
8
Auburn, Indiana
I am trying to get my loader to work after all lines were replaced. The system has 15 gallons of Kubota fluid plus what did not leak out. It shows full on the sight glass (also replaced with brand new one).
I have ran it (engine running at medium speed and control valve being held in position for at least 30 seconds and then moved to another position where it should do something) for an hour.
I only get a little movement (little force on the bucket roll open). I have jacked the loader bucket up (trying to force air out) and the system holds it in the up position but will not move any further up. When control valve moves to the loader lower position- no movement. When the valve is moved to the float position the loader drops.

Any suggestions would be appreciated.
 

D2Cat

Well-known member
Lifetime Member

Equipment
L305DT, B7100HST, TG1860, TG1860D, L4240
Mar 27, 2014
13,888
5,694
113
40 miles south of Kansas City
Are you quick connect in the correct position and are they locking together?

The system will bleed the air out by simply operating the controls (if it's properly connected).

Did the loader work properly before you replaced hoses?
 

PoTreeBoy

Well-known member
Lifetime Member

Equipment
L35 Ford 3930
Mar 24, 2020
2,835
1,547
113
WestTn/NoMs
You have hoses connected incorrectly or a quick coupling not completely seated. Air in the lines is not your problem, the lines will self-bleed.

Even if you just have the bucket lines crossed, it won't just work backwards, it won't work at all.
 

TheOldHokie

Well-known member
Lifetime Member

Equipment
L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Apr 6, 2021
8,928
4,669
113
Myersville, MD
windyridgefarm.us
I am trying to get my loader to work after all lines were replaced. The system has 15 gallons of Kubota fluid plus what did not leak out. It shows full on the sight glass (also replaced with brand new one).
I have ran it (engine running at medium speed and control valve being held in position for at least 30 seconds and then moved to another position where it should do something) for an hour.
I only get a little movement (little force on the bucket roll open). I have jacked the loader bucket up (trying to force air out) and the system holds it in the up position but will not move any further up. When control valve moves to the loader lower position- no movement. When the valve is moved to the float position the loader drops.

Any suggestions would be appreciated.
 

TheOldHokie

Well-known member
Lifetime Member

Equipment
L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Apr 6, 2021
8,928
4,669
113
Myersville, MD
windyridgefarm.us
I am trying to get my loader to work after all lines were replaced. The system has 15 gallons of Kubota fluid plus what did not leak out. It shows full on the sight glass (also replaced with brand new one).
I have ran it (engine running at medium speed and control valve being held in position for at least 30 seconds and then moved to another position where it should do something) for an hour.
I only get a little movement (little force on the bucket roll open). I have jacked the loader bucket up (trying to force air out) and the system holds it in the up position but will not move any further up. When control valve moves to the loader lower position- no movement. When the valve is moved to the float position the loader drops.

Any suggestions would be appreciated.
If the loader wont lower unless in float the power beyond hose is not properly connected. Will the bucket curl?


Dan
 

Nickk

Member

Equipment
L3600 Kubota
Jan 24, 2023
73
8
8
Auburn, Indiana
Thanks for the questions, here are the answers I appreciate the help.
The bucket will curl and dump but with no power (if laying on the ground does not move, in open air it will slowly move)

The loader did work well before I improved it!

I have inspected all couplers are they are seated (took them apart, cleaned them (this was not needed but), reseated them, inspected there position, pulled on each one to be sure they would not come out)

If the system is in mid air (achieved by using a jack to lift it and then actuating the valve in all positions, removing the jack) it stays there for over 24 hours.

In a raised position the boom cylinders have pressure on the raise side and minimal pressure on the retract side.

Rechecked the plumbing (I had marked all connections with color coded zip ties, checked it against the installation guide, and with Kubota USA hose diagrams).

Three point and power steering work great.

The inlet port (on the outlet block under the floor board, closest to the filter) shoots fluid out of the hose when I remove it and actuate the control valve.

If someone has a definitive plumbing schematic for a L3600 with a LA680 loader that would be great.


For troubleshooting should i remove a line and actuate the valve and see what shoots fluid.
 

TheOldHokie

Well-known member
Lifetime Member

Equipment
L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Apr 6, 2021
8,928
4,669
113
Myersville, MD
windyridgefarm.us
Thanks for the questions, here are the answers I appreciate the help.
The bucket will curl and dump but with no power (if laying on the ground does not move, in open air it will slowly move)

The loader did work well before I improved it!

I have inspected all couplers are they are seated (took them apart, cleaned them (this was not needed but), reseated them, inspected there position, pulled on each one to be sure they would not come out)

If the system is in mid air (achieved by using a jack to lift it and then actuating the valve in all positions, removing the jack) it stays there for over 24 hours.

In a raised position the boom cylinders have pressure on the raise side and minimal pressure on the retract side.

Rechecked the plumbing (I had marked all connections with color coded zip ties, checked it against the installation guide, and with Kubota USA hose diagrams).

Three point and power steering work great.

The inlet port (on the outlet block under the floor board, closest to the filter) shoots fluid out of the hose when I remove it and actuate the control valve.

If someone has a definitive plumbing schematic for a L3600 with a LA680 loader that would be great.


For troubleshooting should i remove a line and actuate the valve and see what shoots fluid.
Here are the connections from the tractor to the loader. Pretty damn simple.

Your main symptom is the loader will not lower so a simple test of that circuit:

WITH THE TRACTOR OFF AND THE LOADER IN MID AIR

  1. Disconnect the hose at C and put it in a bucket.
  2. Move the joystick to BOOM DOWN and you should get a flow of oil into the bucket as the loader drops under its own weight.
Dan

Untitled.png
 
Last edited:
  • Like
Reactions: 1 user

Nickk

Member

Equipment
L3600 Kubota
Jan 24, 2023
73
8
8
Auburn, Indiana
Would someone be able to fill in the table in this picture with valve port numbers. This would help me sort out my problems.

thanks
 

PoTreeBoy

Well-known member
Lifetime Member

Equipment
L35 Ford 3930
Mar 24, 2020
2,835
1,547
113
WestTn/NoMs
Here are the connections from the tractor to the loader. Pretty damn simple.

Your main symptom is the loader will not lower so a simple test of that circuit:

WITH THE TRACTOR OFF AND THE LOADER IN MID AIR

  1. Disconnect the hose at C and put it in a bucket.
  2. Move the joystick to BOOM DOWN and you should get a flow of oil into the bucket as the loader drops under its own weight.
Dan

View attachment 113423
This is the file
An example of what I am hoping for is.
A-3
B-1
C-2
Boom extend-
Boom Retract-
Bucket curl-
Bucket dump-
OK, you're in luck, nephew's L3600 was handy.
1 IN B on TheOldHokie's diagram
2 OUT (Tank) D on TOH's diagram
3 (Power Beyond) C on TOH's diagram
4 Boom up, extend
5 Bucket curl, retract
6 Boom down, retract
7 Bucket dump, extend
 

TheOldHokie

Well-known member
Lifetime Member

Equipment
L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Apr 6, 2021
8,928
4,669
113
Myersville, MD
windyridgefarm.us
Would someone be able to fill in the table in this picture with valve port numbers. This would help me sort out my problems.

thanks
OK, you're in luck, nephew's L3600 was handy.
1 IN B on TheOldHokie's diagram
2 OUT (Tank) D on TOH's diagram
3 (Power Beyond) C on TOH's diagram
4 Boom up, extend
5 Bucket curl, retract
6 Boom down, retract
7 Bucket dump, extend
If the boom will float the workport couplers and tank are working. My guess is the coupler on C is not. Easily verified in a matter of minutes as described.

That would also have the pump relieving full time through the pressure relief (2500 PSI.) and the 3pt would not be working along with the loader.

Dan
 

Nickk

Member

Equipment
L3600 Kubota
Jan 24, 2023
73
8
8
Auburn, Indiana
OK, you're in luck, nephew's L3600 was handy.
1 IN B on TheOldHokie's diagram
2 OUT (Tank) D on TOH's diagram
3 (Power Beyond) C on TOH's diagram
4 Boom up, extend
5 Bucket curl, retract
6 Boom down, retract
7 Bucket dump, extend

Thanks!!! Great actionable steps!!
 

Nickk

Member

Equipment
L3600 Kubota
Jan 24, 2023
73
8
8
Auburn, Indiana
Here are the connections from the tractor to the loader. Pretty damn simple.

Your main symptom is the loader will not lower so a simple test of that circuit:

WITH THE TRACTOR OFF AND THE LOADER IN MID AIR

  1. Disconnect the hose at C and put it in a bucket.
  2. Move the joystick to BOOM DOWN and you should get a flow of oil into the bucket as the loader drops under its own weight.
Dan

View attachment 113423

Thanks, great information.
 

Nickk

Member

Equipment
L3600 Kubota
Jan 24, 2023
73
8
8
Auburn, Indiana
I took hose C off and started the tractor; there was high flow into the bucket.
I pull the valve back (to raise the loader) and the flow decreases significantly.
I will post videos and a picture as soon as I get it to work.

The loader does not lift but it does lower now in the control position.
It dumps and rolls, slow and no power.
It stays in the up position.
 

Nickk

Member

Equipment
L3600 Kubota
Jan 24, 2023
73
8
8
Auburn, Indiana
So I have 2X checked hose routing and I think it is right.
I removed the line at plug C.
With tractor running it is coming out at a high flow; but not like it is under high pressure. with hose removed I pulled the control back and the loader does not lift but the flow at point C decreases significantly.

For some reason the lower seams to work when in the lower position (not float).
Curl and dump work but very slow and little force.
If I dump it will put a little pressure on the loader and if I move the control into raise position it relieves that pressure and holds the loader at that height.
I have attached some a picture of the site glass for fluid level. Videos coming
 

Attachments

TheOldHokie

Well-known member
Lifetime Member

Equipment
L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Apr 6, 2021
8,928
4,669
113
Myersville, MD
windyridgefarm.us
I took hose C off and started the tractor; there was high flow into the bucket.
I pull the valve back (to raise the loader) and the flow decreases significantly.
I will post videos and a picture as soon as I get it to work.

The loader does not lift but it does lower now in the control position.
It dumps and rolls, slow and no power.
It stays in the up position.
I was quite clear - disconnect C with the tractor OFF. Starting it will pump all of the oil out into your bucket in a matter of a minute or two!!! If you are going to start the tractor put the end of the hose in the transmission filler.

If you are getting flow and it does not lift with that hose disconnected the lift cylinders are not plumbed correctly.

Go back and run the test exactly as I described - tractor off, loader raised, hose in bucket, and move joystick to lower. You should get oil out of the hose and the boom should drop.

Dan
 
Last edited:
  • Like
Reactions: 1 users

Nickk

Member

Equipment
L3600 Kubota
Jan 24, 2023
73
8
8
Auburn, Indiana
Sorry about that; I will complete tonight.

This is what I did:
Tractor not running- small amount of fluid running out when hose removed
Tractor starts - study flow of fluid not high pressure (maybe a gallon in 30 seconds)
Pull control valve to raise - slower flow.
Picture just shows the fluid is full.
thanks
 

Attachments

TheOldHokie

Well-known member
Lifetime Member

Equipment
L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Apr 6, 2021
8,928
4,669
113
Myersville, MD
windyridgefarm.us
Sorry about that; I will complete tonight.

This is what I did:
Tractor not running- small amount of fluid running out when hose removed
Tractor starts - study flow of fluid not high pressure (maybe a gallon in 30 seconds)
Pull control valve to raise - slower flow.
Picture just shows the fluid is full.
thanks
That is all normal and confirms your power beyond loop is flowing. It does not provide any clues to what is going on at the work ports.

A static lower test will confirm operation of the work port circuit. I am pretty sure that is not working. Once we confirm that we can move on to finding the problem there. Probably a bad coupler or crossed lines.

One step at a time focusing on just one circuit will find the problem faster than the shotgun appproach.

Dan
 

Nickk

Member

Equipment
L3600 Kubota
Jan 24, 2023
73
8
8
Auburn, Indiana
I could not get the videos on this site so here is a share link that should work.
One video I trace the hoses, sorry for the bumpy picture.
The other video is of the loader operating at full power and control in the full open position (very little power and slow).