New Holland 4880/D1210 Baler Load Sensor

[nxy]

I have an elderly New Holland 4880 (same as a D1210 and called a 595 in the USA).

At the end of last season the bale density became pretty erratic with the rams on the bale chamber moving in and out randomly producing occasional soft useless bales that were so loose we struggled to pick them up. No error messages came up on the control box and the density reading on the cab box remained fairly static. It was like something would stick open and allow the oil back to the tank for a while and then it would unstick and tighten up the rams again.

I bought a manual on line for the baler and that suggests recalibrating the load sensor regularly so I thought I would give it a go. They say to undo the big drawbolt through the load sensor and then tighten back up until the yellow LED comes on in the box on the side of the baler.

I have a red LED which never comes on and green and yellow LEDs which remain on constantly no matter if the bolt is finger tight or if I tighten to the point of me bouncing on a 6 foot scaffold pole.

Firstly I am not sure the manual is right for my baler, so am I following the right procedure and secondly if it's right is it safe to assume the Load Sensor is dead?

Any suggestions?

 

[Goweresque]

Is it not possible to set the pressure in the rams manually and bypass the load sensing process? My old Hesston 4600 has load sensing but I could never get it to work properly, so I just switch to manual and set the pressure that way. Is there no Auto/Manual switch somewhere on the baler?

 

[bobk]

Is it not possible to set the pressure in the rams manually and bypass the load sensing process? My old Hesston 4600 has load sensing but I could never get it to work properly, so I just switch to manual and set the pressure that way. Is there no Auto/Manual switch somewhere on the baler?

My thoughts too , the auto load sensing on the hesston is a nightmare .

 

[nxy]

Thanks for that.

When I tried it in manual it pulled the rams in so tight I thought it would end in a big bang so didn't try for long. It also says in the manual you need a "shunt" to plug in to replace the control box, for some reason.

Perhaps Manual is the way to go. How do you set the pressure if its set too high?

I actually started to think replacing the rams with a couple of top links was a potential solution bearing in mind the age and value of the baler it's not worth spending any money on.

 

[Goweresque]

Thanks for that.

When I tried it in manual it pulled the rams in so tight I thought it would end in a big bang so didn't try for long. It also says in the manual you need a "shunt" to plug in to replace the control box, for some reason.

Perhaps Manual is the way to go. How do you set the pressure if its set too high?

I actually started to think replacing the rams with a couple of top links was a potential solution bearing in mind the age and value of the baler it's not worth spending any money on.

If there is a manual setting there must be some way of setting the pressure manually. Does the manual not tell you how to do it?

There must be a hydraulic valve somewhere that controls the ram pressure when in auto mode, could you not just replace that with a manually adjustable valve? All you need is something that allows a controllable amount of oil pressure to the rams and dumps the rest back to tank. Are you sure the ram seals themselves aren't leaking? Its easy to assume they're fine and its the electronics at fault.

 

[nxy]

If there is a manual setting there must be some way of setting the pressure manually. Does the manual not tell you how to do it?

There must be a hydraulic valve somewhere that controls the ram pressure when in auto mode, could you not just replace that with a manually adjustable valve? All you need is something that allows a controllable amount of oil pressure to the rams and dumps the rest back to tank. Are you sure the ram seals themselves aren't leaking? Its easy to assume they're fine and its the electronics at fault.

Just looked in the book and there is an adjustment on a pressure relief valve.

Thinking about it now, it's logical that the relief valve pressure is set high for Auto use when the electronics normally control things but can be dropped to control pressure in Man.

Ram seals were on the list to look at next. Its a bank holiday here and too wet for work so that can wait for tomorrow.

 

[bobk]

@Hesston4860s knows a bit about 5 string nh balers

 

[Hesston4860s]

Should be a switch on the box in the baler for auto/manual, put it in manual and set the pressure with the relief valve. The relief valve will be screwed in all the way and backed out 4 turns to run in auto, so set way to high for manual mode.
But check your stuffer switch is working properly as it triggers the density circuit, if it not working or only sometimes you’ll end up with the symptoms your describing. The stuffer switch and knotter switch are the same so can be swapped over for trouble shooting purposes !.
you shouldnt need a shunt either on a 4880/1210, fairly sure that’s only on the later BB series balers.

 

[schmidt96]

Hi I have a d1210 the density rams have pulled right down and the pressure is right up have looked in white box I have know lights on the silver box should they be always lights on. Is there an voltage I can check

 

[schmidt96]

There are now a yellow an green light showing