My Tractor Forum banner
1 - 20 of 65 Posts

·
Registered
Joined
·
44 Posts
Discussion Starter · #1 ·
Have a Ford 545 backhoe. Recently notices the hydraulics to be very slow and weak. Cannot lift itself anymore. Been removing large rocks recently. No change in morning when cold or warm during the day. Thought it might be engine issue so I replace fuel filter and bled injectors. Still no change.



Hydraulic main filter changed.
Hydraulic mesh filter cleaned in reservoir.
Toped off oil to level.
Replaced oil 150 hours ago in entire hydraulic system.
Tire Wheel Cloud Land vehicle Vehicle
 

·
Premium Member
Joined
·
9,248 Posts
Check the drive shaft for the front mounted hydraulic pump. The splines are known to strip over time. The pump itself has a splined shaft that goes into a splined coupler on a double u-joint assembly, and then other end of the second u-joint is bolted to the crankshaft pulley. It might appear to spin the pump fine when it's not trying to do any work, so you may need someone to operate the hydrulics and try to lift the tractor with the front bucket or something similar while you watch the pump shaft to see if it slips.
 
  • Like
Reactions: Vigo

·
Registered
Joined
·
44 Posts
Discussion Starter · #3 ·
Check the drive shaft for the front mounted hydraulic pump. The splines are known to strip over time. The pump itself has a splined shaft that goes into a splined coupler on a double u-joint assembly, and then other end of the second u-joint is bolted to the crankshaft pulley. It might appear to spin the pump fine when it's not trying to do any work, so you may need someone to operate the hydrulics and try to lift the tractor with the front bucket or something similar while you watch the pump shaft to see if it slips.
I will check and see if it continues spinning correctly under hydraulic pressure.
 

·
Registered
Joined
·
44 Posts
Discussion Starter · #4 ·
Check the drive shaft for the front mounted hydraulic pump. The splines are known to strip over time. The pump itself has a splined shaft that goes into a splined coupler on a double u-joint assembly, and then other end of the second u-joint is bolted to the crankshaft pulley. It might appear to spin the pump fine when it's not trying to do any work, so you may need someone to operate the hydrulics and try to lift the tractor with the front bucket or something similar while you watch the pump shaft to see if it slips.
The pump shaft seems fine when under load. Anything else to check for?
 

·
Super Moderator
Joined
·
24,001 Posts
The video shows a lack of effect when one control is actuated, What happens when each of the other controls is actuated?

If all controls show the same results, either the relief valve spring has broken or the relief valve poppet is hung up on some debris allowing the fluid to go back to tank with little restriction, or the pump is not functioning correctly.

If only the one control has that effect, the associated cylinder seals are leaking by and the cylinder needs to be re-sealed.
 

·
Registered
Joined
·
44 Posts
Discussion Starter · #7 ·
The video shows a lack of effect when one control is actuated, What happens when each of the other controls is actuated?

If all controls show the same results, either the relief valve spring has broken or the relief valve poppet is hung up on some debris allowing the fluid to go back to tank with little restriction, or the pump is not functioning correctly.

If only the one control has that effect, the associated cylinder seals are leaking by and the cylinder needs to be re-sealed.
All the controls from the bucket to the rear is weak. I’m a little new to hydraulics. Where to look for the spring or the valve poppet? In the front of the backhoe near the pump or the rear?
Automotive tire Wood Automotive wheel system Gas Auto part
 

·
Premium Member
Joined
·
9,248 Posts
The pump shaft keeps spinning fine in the first video, so it's not worn shaft spines. There are two releif valves in that system, one inside the loader control valve and the other inside the backhoe control valve. That is too new of a model for me to be intimately familiar with, but I believe that the backhoe control valve is the first to receive power from the pump, and then the loader control valve receives power from the power beyond port on the backhoe control valve, so if both the loader and the backhoe are exhibiting the symptoms, and if it is a relief valve that has the problem, it is most likely the one inside the backhoe control valve. The relief valves are probably not serviceable, and if it is one of the relief valves, it will need to be replaced as a unit. The assembly of the relief valve includes shims to set the exact relief pressure and those are set at the factory when they make the valve. The relief valve simply unscrews from the body of the control valve, so it is not too difficult to replace.

As Tudor said, the pump itself could be not functioning properly. I recommend that you get the Service Manul for that tractor, as it will have procedures for troubleshooting this type of problem to determine the cause, or if you're not sure of your hydraulics skills, take it to a New Holland dealership if you have one close by, as they wil be able to do it, but it will be more expensive than doing it yourself.
 
  • Like
Reactions: TUDOR

·
Registered
Joined
·
44 Posts
Discussion Starter · #10 ·
I found a small black rubber pieces in hydraulic oil reservoir screen. Textured on the outside smooth on the inside. Any idea? Maybe some kind of seal or hydraulic line piece? Pretty small in diameter. Quarter for comparison.
Textile Sleeve Grey Font T-shirt
Road surface Grey Asphalt Wood Font
 

·
Premium Member
Joined
·
9,248 Posts
Looks like the inside surface of a hydraulic hose is deteriorating. The hydraulic hoses have steel braiding in them, and rubber to the inside and outside of the steel braiding When the interior of the hose deteriorates like that and becomes detatched, the inside surface of the hose is smooth and it is textured on the outside to match the pattern of the steel braid. That could be what is blocking the flow and causing the issues you are having. You should inspect all of the hoses to see how many may need to be replaced, and replace any that have deterioration like that.

May need to clean out the pump, the control valves, and the cylinders if any of that stuff made its way into any of those components as well.
 

·
Registered
Joined
·
44 Posts
Discussion Starter · #12 ·
Looks like the inside surface of a hydraulic hose is deteriorating. The hydraulic hoses have steel braiding in them, and rubber to the inside and outside of the steel braiding When the interior of the hose deteriorates like that and becomes detatched, the inside surface of the hose is smooth and it is textured on the outside to match the pattern of the steel braid. That could be what is blocking the flow and causing the issues you are having. You should inspect all of the hoses to see how many may need to be replaced, and replace any that have deterioration like that.

May need to clean out the pump, the control valves, and the cylinders if any of that stuff made its way into any of those components as well.
I replaced over 10 hydraulic hoses that were in bad condition in the past few months. Most of them are fine now. That looks like a very small diameter hose that fell apart before. Not sure if I have one that size even. I think the issue is a cracked spring on one of the control valves or busted seal that releases pressure internally. I’m just not sure where to start taking it apart. I found the feed line and the return line. So the rear of the backhoe is the main 1st supplies pressure then it comes back to the front loader. Is there a main supply pressure valve on the first input and output on the rear controls. Picture below. Any help is greatly appreciated.
Automotive tire Motor vehicle Gas Auto part Automotive wheel system
Wood Gas Auto part Metal Pipe
 

·
Premium Member
Joined
·
9,248 Posts
The backhoe isn't included in the parts drawing for the 545D tractor. It had a loader standard but the backhoe was an option, and it could be one of a couple of different backhoe models. I would need to know the model of the backhoe to be able to lookup the control valve to see where the pressure relief valve is located on that particular control valve.
 

·
Premium Member
Joined
·
9,248 Posts
It does look similar to the control valve on the backhoe of the 555D, and that one had multiple pressure relief valves with different pressure ratings for different valves in the block. They all screwed into the top or bottom of the valve housing. The relief valves on the 555D backhoe control valve are labelled 8, 9, 10 & 11 in the parts drawing at the link below:

Link to parts drawing of 555D backhoe control valve

I believe I see similar relief valves on the top and bottom of your control valve.

You really should get a service manual for that tractor. Having the proper troubleshooting steps would help immensely.
 
  • Like
Reactions: TUDOR

·
Registered
Joined
·
44 Posts
Discussion Starter · #15 ·
The backhoe isn't included in the parts drawing for the 545D tractor. It had a loader standard but the backhoe was an option, and it could be one of a couple of different backhoe models. I would need to know the model of the backhoe to be able to lookup the control valve to see where the pressure relief valve is located on that particular control valve.
I believe it’s a 545A Industrial 1984-1988.
Motor vehicle Font Plant Gas Tree
 

·
Premium Member
Joined
·
9,248 Posts
Yes, DD4 is a 545A. Sorry, I thought you were the same person who was asking about a"545" last week and he eventually said that it was a 545D. A backhoe was an option on the 545A also, but there is a parts drawing for the backhoe control valve in the parts listing for the 545A. It looks the same as the 555D control valve, so the relief valves are screwed into the top and bottom of the control valve body.

The odd thing is that according to all of my references, as well as the New Holland parts site, the 545A was only made from 1984 to 1988, and the Unit Number on your sticker says that it was assembled on April 23 of some year that ended in a 2, and the Tractor Number (serial number), C690156, is a 1982 serial number, but that tractor model was never made in a year that ended in a 2. The plain 545 (no letter at the end) was made when that serial number was produced, so maybe it is a plain 545. The parts drawings for all of the backhoe control valves that I could find are basically the same for all backhoes from the late 1970's through the late 1980's, so that parts drawing that I linked to should be correct no matter which model it is.
 

·
Registered
Joined
·
44 Posts
Discussion Starter · #17 ·
Yes, DD4 is a 545A. Sorry, I thought you were the same person who was asking about a"545" last week and he eventually said that it was a 545D. A backhoe was an option on the 545A also, but there is a parts drawing for the backhoe control valve in the parts listing for the 545A. It looks the same as the 555D control valve, so the relief valves are screwed into the top and bottom of the control valve body.

The odd thing is that according to all of my references, as well as the New Holland parts site, the 545A was only made from 1984 to 1988, and the Unit Number on your sticker says that it was assembled on April 23 of some year that ended in a 2, and the Tractor Number (serial number), C690156, is a 1982 serial number, but that tractor model was never made in a year that ended in a 2. The plain 545 (no letter at the end) was made when that serial number was produced, so maybe it is a plain 545. The parts drawings for all of the backhoe control valves that I could find are basically the same for all backhoes from the late 1970's through the late 1980's, so that parts drawing that I linked to should be correct no matter which model it is.
I’m looking around for the backhoe attachment model. I believe it’s a Ford 765 backhoe attachment.
 

·
Registered
Joined
·
44 Posts
Discussion Starter · #18 ·
Yes, DD4 is a 545A. Sorry, I thought you were the same person who was asking about a"545" last week and he eventually said that it was a 545D. A backhoe was an option on the 545A also, but there is a parts drawing for the backhoe control valve in the parts listing for the 545A. It looks the same as the 555D control valve, so the relief valves are screwed into the top and bottom of the control valve body.

The odd thing is that according to all of my references, as well as the New Holland parts site, the 545A was only made from 1984 to 1988, and the Unit Number on your sticker says that it was assembled on April 23 of some year that ended in a 2, and the Tractor Number (serial number), C690156, is a 1982 serial number, but that tractor model was never made in a year that ended in a 2. The plain 545 (no letter at the end) was made when that serial number was produced, so maybe it is a plain 545. The parts drawings for all of the backhoe control valves that I could find are basically the same for all backhoes from the late 1970's through the late 1980's, so that parts drawing that I linked to should be correct no matter which model it is.
So I got the repair manuals for the 765 backhoe and for the 545 tractor. The 545 tractor manual is kind of pointless. 800 pages of info but nothing much on hydraulics. I performed a pressure test on the 765 backhoe today on the main control valve. The range should be 2450-2600 psi. The psi spikes to 2500 psi and then drops to 2000 when the rpm drop on the end of its stroke. When the 500 psi drop happens is when the engine bogs down. Do you think this is a engine issue or hydraulics issues. Why would it bog down on the top of a stroke?
Font Material property Paper Publication Poster
 

·
Premium Member
Joined
·
9,248 Posts
If you keep the control valve in the position for the cylinder to keep moving when the cylinder reaches the end of the stoke, then the pressure should build until it reaches the relief pressure of the relief valve, and then the relief valve should open and the pressure should drop back some, so that is expected. Is it still exhibiting the original symptoms after you removed those pieces of hose from the screen?
 

·
Registered
Joined
·
44 Posts
Discussion Starter · #20 ·
If you keep the control valve in the position for the cylinder to keep moving when the cylinder reaches the end of the stoke, then the pressure should build until it reaches the relief pressure of the relief valve, and then the relief valve should open and the pressure should drop back some, so that is expected. Is it still exhibiting the original symptoms after you removed those pieces of hose from the screen?
Yes its the same issue after changing filter and cleaning screen out. I don’t remember the rpm dropping like that when I was digging in the past. I tried digging a little yesterday and it was week and slow hydraulics like before so I parked it again.
 
1 - 20 of 65 Posts
Top