Air in hydraulic system

[Michiganpat]

How do you get air out of the system I changed fluid and filters and now I can’t get anything to work it’s a 96 M5400

 

[BAP]

You should not need to bleed air out of the system after an oil and filter change. If you have no hydraulics then you have something more seriously wrong. Was it a routine service you did? Or were you changing because you were having problems?

 

[TheOldHokie]

How do you get air out of the system I changed fluid and filters and now I can’t get anything to work it’s a 96 M5400

Its not air in the system. Sounds like your pump isnt pumping. Let it run for a few minutes and cycle the hydraulic controls. If its still not working check the filter.

Dan

 

[JimDeL]

Different model, but my shop manual says to let the tractor run for 10~15 minutes at a high idle after a fluid change before trying to use it. YMMV

 

[Michiganpat]

You should not need to bleed air out of the system after an oil and filter change. If you have no hydraulics then you have something more seriously wrong. Was it a routine service you did? Or were you changing because you were having problems?

Just routine change everything worked before

 

[TheOldHokie]

Just routine change everything worked before

Read my earlier post. My guess is your pump is not priming for some reason. I would look hard at the new filter. Believe it or not but people have installed them with some of the pkastic stoll stuck to the end... If the pump is working the filter will be full of oil.

Dan

 

[Michiganpat]

Read my earlier post. My guess is your pump is not priming for some reason. I would look hard at the new filter. Believe it or not but people have installed them with some of the pkastic stoll stuck to the end... If the pump is working the filter will be full of oil.

Dan

Ok I’ll check it out

 

[Fedup]

How do you get air out of the system I changed fluid and filters and now I can’t get anything to work it’s a 96 M5400

Does the steering work? If that's not working either then you need to bleed the pump. Loosen the bolts holding the pressure lines on top of the pump. Back them off a couple turns. Put a pan under the pump. Set the lift arm control fully down. Start the engine and run at a fast idle for a few seconds and see if oil starts flowing from the pump or not.

 

[Michiganpat]

Does the steering work? If that's not working either then you need to bleed the pump. Loosen the bolts holding the pressure lines on top of the pump. Back them off a couple turns. Put a pan under the pump. Set the lift arm control fully down. Start the engine and run at a fast idle for a few seconds and see if oil starts flowing from the pump or not.

Does the steering work? If that's not working either then you need to bleed the pump. Loosen the bolts holding the pressure lines on top of the pump. Back them off a couple turns. Put a pan under the pump. Set the lift arm control fully down. Start the engine and run at a fast idle for a few seconds and see if oil starts flowing from the pump or not.

w

Does the steering work? If that's not working either then you need to bleed the pump. Loosen the bolts holding the pressure lines on top of the pump. Back them off a couple turns. Put a pan under the pump. Set the lift arm control fully down. Start the engine and run at a fast idle for a few seconds and see if oil starts flowing from the pump or not.

ill definitely try that because steering is stiff I figured it was something like that thanks

 

[lugbolt]

it's a self-bleeding system as most kubota's are

removing high pressure hoses while running can be very, very dangerous. don't do it.

did you clean the suction screen (if it has one, I don't remember?)??

 

[Michiganpat]

it's a self-bleeding system as most kubota's are

removing high pressure hoses while running can be very, very dangerous. don't do it.

did you clean the suction screen (if it has one, I don't remember?)??

Doesn’t have one that I know of

 

[TheOldHokie]

Doesn’t have one that I know of

Your pump is not pumping. Take the new filter off and see if its full of oil. My guess is its dry.

Dan

 

[lugbolt]

Doesn’t have one that I know of

ok so the filters are on the suction side. Pull the line off of the pump inlet and see if it's got oil flowing to it. If it does, and it will likely run out in a hurry so be prepared to put the hose back on quickly, then you'll need to work up towards the pump.

In 30 years I replaced two hydraulic pumps. First one on a L35 second one L48. One thing I learned was that the pump may or may not be bad, remember it's gotta get oil TO the pump for it to work. Dented/kinked suction (feed) line can cause some issues, filters on the suction side, and screens (which you don't have). Occasionally just junk in the transmission where the suction hose is, plugs the hole up and the pump won't pick it up. That one threw us for a loop. Also did one once (don't remember what model) that had a defective filter. That's what we called it, but me as a young inexperienced tech just got in a hurry to throw a new filter on and didn't think about it much. There was some plastic on the filter that keeps the crud out while its in the box. I didn't take it off, never thought about it until I did the service and it wouldn't lift the loader. Spent, probably a half day, trying to figure that out. Huh, must be a "bad filter". Took another filter out of the box, pulled the plastic off, unscrewed the other new one, put the new new one on and it worked fine. Kubota rep showed up weeks later and I was explaining it to him and he said "did you take the plastic off?". Got me to thinking, and since we warrantied the filter and had to keep it for 6 months, I pulled it off of the shelf and took a peek down inside of it...yep...plastic still on it, I just forced the filter to screw onto the nipple by piercing through the plastic. Lesson learned.

Even techs aren't perfect. We learn from our mistakes, and a tech who doesn't make a mistake does not exist.

 

[Michiganpat]

I

ok so the filters are on the suction side. Pull the line off of the pump inlet and see if it's got oil flowing to it. If it does, and it will likely run out in a hurry so be prepared to put the hose back on quickly, then you'll need to work up towards the pump.

In 30 years I replaced two hydraulic pumps. First one on a L35 second one L48. One thing I learned was that the pump may or may not be bad, remember it's gotta get oil TO the pump for it to work. Dented/kinked suction (feed) line can cause some issues, filters on the suction side, and screens (which you don't have). Occasionally just junk in the transmission where the suction hose is, plugs the hole up and the pump won't pick it up. That one threw us for a loop. Also did one once (don't remember what model) that had a defective filter. That's what we called it, but me as a young inexperienced tech just got in a hurry to throw a new filter on and didn't think about it much. There was some plastic on the filter that keeps the crud out while its in the box. I didn't take it off, never thought about it until I did the service and it wouldn't lift the loader. Spent, probably a half day, trying to figure that out. Huh, must be a "bad filter". Took another filter out of the box, pulled the plastic off, unscrewed the other new one, put the new new one on and it worked fine. Kubota rep showed up weeks later and I was explaining it to him and he said "did you take the plastic off?". Got me to thinking, and since we warrantied the filter and had to keep it for 6 months, I pulled it off of the shelf and took a peek down inside of it...yep...plastic still on it, I just forced the filter to screw onto the nipple by piercing through the plastic. Lesson learned.

Even techs aren't perfect. We learn from our mistakes, and a tech who doesn't make a mistake does not exist.

I will check it out haven’t had a chance yet