Backhoe John Deere 410d hydraulics

jbanderson127 · Jan 21, 2015

I have a 1995 john Deere 410d backhoe. The hydraulics seem to be a little week on it. Here's what it's doing. Maybe someone can help me figure out what it might be and where to start diagnosis. When operating the loader or the hoe when you pull back on a lever to activate it ( doesn't matter which one. The response is the same) at first it seems sluggish like it doesn't want to move for like one second and then it moves at full speed all the way through the end of the cylinder stoke. You can stop it and activate the lever again to raise the loader or operate the hoe and it does this every time. The sluggish one second delay then full speed motion of the cylinder(s). The loader seems to have plenty of lifting power and will pick up anything you give it. However the hoe seems a little weak when digging. You have to ease up on the main boom then pull in the dipper stick some, ease up on the main boom again and pull in the dipper stick some more back and forth in a fast repetive motion just to fill up the hoe bucket in relatively soft dirt. Doesn't seem to load engine either when hoe gets to digging hard. Hydraulic oil level is full. However it is full of tiny bubbles to the point it looks milky after being run a while. Steering and reverser work fine. Any help or ideas would be appreciated.

hosspuller · Jan 21, 2015

Sounds like you're sucking air into the hydraulic pump. The air in the cylinders is causing the delay. Check the seal on the hydraulic filter... then every fitting on the suction line to the pump.

jbanderson127 · Jan 25, 2015

jbanderson127 said:
I have a 1995 john Deere 410d backhoe. The hydraulics seem to be a little week on it. Here's what it's doing. Maybe someone can help me figure out what it might be and where to start diagnosis. When operating the loader or the hoe when you pull back on a lever to activate it ( doesn't matter which one. The response is the same) at first it seems sluggish like it doesn't want to move for like one second and then it moves at full speed all the way through the end of the cylinder stoke. You can stop it and activate the lever again to raise the loader or operate the hoe and it does this every time. The sluggish one second delay then full speed motion of the cylinder(s). The loader seems to have plenty of lifting power and will pick up anything you give it. However the hoe seems a little weak when digging. You have to ease up on the main boom then pull in the dipper stick some, ease up on the main boom again and pull in the dipper stick some more back and forth in a fast repetive motion just to fill up the hoe bucket in relatively soft dirt. Doesn't seem to load engine either when hoe gets to digging hard. Hydraulic oil level is full. However it is full of tiny bubbles to the point it looks milky after being run a while. Steering and reverser work fine. Any help or ideas would be appreciated.

Ok
So I had to take the loader bucket tilt cylinder off to repair it. After I had disconnected the lines I had to crank the backhoe to move it. Oil was being pumped out of one of the lines and none of the valves were open. Is this normal? Doesn't seem like it to me.

jd110 · Jan 25, 2015

It is normal to have some leakage from disconnected cylinder hoses when engine is running. If it was forcefully spraying oil, then you have a problem. Spool valves don't seal 100%. If the bucket stays in position with engine running, you should be ok. I agree that you have a problem with air being sucked into the system. This can also be caused by clogged filters or sump screen.

Tx Jim · Jan 25, 2015

Control valve should not have excessive oil flow when lever is in neutral. High pressure internal leaks can cause hyd pump to cavitate(run out of oil). I would suggest to get a gauge nd check hyd stand-by pressure which should be 2755 psi.

jbanderson127 · Jan 25, 2015

jd110 said:
It is normal to have some leakage from disconnected cylinder hoses when engine is running. If it was forcefully spraying oil, then you have a problem. Spool valves don't seal 100%. If the bucket stays in position with engine running, you should be ok. I agree that you have a problem with air being sucked into the system. This can also be caused by clogged filters or sump screen.

The bucket does stay in position when the engine is running. I am planning on changing out the oil and filters this week. I know the screen has never been changed. Where would the sump screen be located on this machine?

Tx Jim · Jan 25, 2015

Screen is parts key 41 or 70 depending on tractor serial number

jbanderson127 · Jan 25, 2015

Tx Jim said:
Screen is parts key 41 or 70 depending on tractor serial number

Thanks Jim for the info. The serial number is 789024. Where would the pressure relief valve be on this machine?

Tx Jim · Jan 25, 2015

On the hyd pump in front of the radiator. Stroke control valve screw is parts key 3. According to your tractor SN screen location should be per the 1st photo I posted

jbanderson127 · Jan 25, 2015

Tx Jim said:
On the hyd pump in front of the radiator. Stroke control valve screw is parts key 3. According to your tractor SN screen location should be per the 1st photo I posted

thanks Jim. I am gonna have a look at that too. Anything I need to know about this valve? Also as per my previous post why do I seem to have plenty of hydraulic power at the front of the machine for the loader yet when I use the hoe it doesn't seem that strong. When I pick the machine up off the ground with the hoe it picks it right up with no problem for about the first 8 -10 inches then it just won't pick it up any further. Doesn't cavitate or anything. The engine doesn't load up like the hydraulics are under load or anything. Also does this when your digging and crowding the bucket. Gets a little load on it and stops crowding. No engine load or anything. I don't think it's the pump since the loader has plenty of power and if you don't fully open a valve on the hoe or the loader then the engine loads up at that point. Hope this makes sense.