Page 2 of 2 FirstFirst 12
Results 31 to 52 of 52

Thread: mf3075 link arms bypass

  1. #31
    davedb
    Guest

    Re: mf3075 link arms bypass

    Quote Originally Posted by hoff135 View Post
    Why then does the engine need to be running to lower the linkage? even pressing the end of the solenoid doesn't lower the arms unless the engine is running? On my tractor anyway
    i think it is the alternator that needs to be running for the arms to function, on my 3630 when the alternator went knackered, nothing would work, was stuck in low box ect

    best thing to try is get a live feed from the battery/starter and unplug the solenoids on the linkage valve, touch the feed on and see if it will lift or lower.

  2. #32
    Spud
    Guest

    Re: mf3075 link arms bypass

    I'd change the lift/lower switch on the console first, not the whole panel just the switch, relatively cheap and easy. Our 3075 has nearly 9000hrs and is on its third switch. Other thing is check max lift height dial, ours goes to constant pump when turned to max height, if on say, fert spreader, once arms at top, other services slow down because of this. It never used to do this, must need adjusting.
    Thinking about it, is the up light on on the console? If so, disconnect the external green buttons on the mudguard, they can give trouble in orrible wet weather.

    Spud.

  3. #33
    hoff135
    Guest

    Re: mf3075 link arms bypass

    Quote Originally Posted by Cowabunga View Post
    I've no idea. The rams are obviously single acting. The control valve, where the solenoids are, must divert oil to the rams when activated one way, allow oil to flow through when not, and allow oil trapped in the rams to be dumped back to the sump when activated the other way and therefore lower the links. It is pretty well as simple as that.

    Perhaps you were not pressing the right way or hard enough on the solenoid ends?
    perhaps not, anyway im not to concerned about it.

    Quote Originally Posted by davedb View Post
    i think it is the alternator that needs to be running for the arms to function, on my 3630 when the alternator went knackered, nothing would work, was stuck in low box ect

    best thing to try is get a live feed from the battery/starter and unplug the solenoids on the linkage valve, touch the feed on and see if it will lift or lower.
    most likely needs the extra v to operate the solenoid properly.

    anyway sorry to clutter up someone else's thread.

  4. #34
    MF-ANDY
    Guest

    Re: mf3075 link arms bypass

    Quote Originally Posted by Orcadian View Post
    It could be one of your green buttons either stuck in or one on the wing got wet and shorting out causing the lift to be in constant pumping
    this would light the raise led on the panel and he dosent mention that

  5. #35
    MF-ANDY
    Guest

    Re: mf3075 link arms bypass

    Quote Originally Posted by hoff135 View Post
    Why then does the engine need to be running to lower the linkage? even pressing the end of the solenoid doesn't lower the arms unless the engine is running? On my tractor anyway
    there is a pilot operated check valve in the lift control block hence you need pressure to release the oil in the rams

  6. #36
    MF-ANDY
    Guest

    Re: mf3075 link arms bypass

    op has tested solenoid wiring and gets 12v when lifting and lowering and spools work so fault must lie in lift control valve

  7. #37
    cooper
    Guest

    Re: mf3075 link arms bypass

    pump was repaced de to just being slow and new one cured that. iv taken the wires off the selinoid and it is still trying to lift the arms all the time so must be stuck valve. just been back out now its cooled down and its steering fine again and not screaching so in hopeing the pump is ok
    daft think is when i got to pull the manito out i tryed driveing it and it came out with a proper driver on it so tractor wasnt needed .
    next move i think is the lift lower valves off the left hand side and see whats in there. maybe a broken or stuck spring? thats if its something i can get into to play with?

  8. #38
    hoff135
    Guest

    Re: mf3075 link arms bypass

    Quote Originally Posted by cooper View Post
    pump was repaced de to just being slow and new one cured that. iv taken the wires off the selinoid and it is still trying to lift the arms all the time so must be stuck valve. just been back out now its cooled down and its steering fine again and not screaching so in hopeing the pump is ok
    daft think is when i got to pull the manito out i tryed driveing it and it came out with a proper driver on it so tractor wasnt needed .
    next move i think is the lift lower valves off the left hand side and see whats in there. maybe a broken or stuck spring? thats if its something i can get into to play with?
    Don't suppose the lift solenoid is stuck in the operating position? Maybe that's not possible though?

  9. #39
    cooper
    Guest

    Re: mf3075 link arms bypass

    i will be checking that first are you ready for yours to follow with same issues :lolk:

  10. #40
    hoff135
    Guest

    Re: mf3075 link arms bypass

    Quote Originally Posted by cooper View Post
    i will be checking that first are you ready for yours to follow with same issues :lolk:
    Noooooooooooo!!!! Dont say that!

  11. #41
    MF-ANDY
    Guest

    Re: mf3075 link arms bypass

    Quote Originally Posted by hoff135 View Post
    Don't suppose the lift solenoid is stuck in the operating position? Maybe that's not possible though?
    swap them end for end. this can be done with the lift valve still on the tractor.

  12. #42
    kmac
    Guest

    Re: mf3075 link arms bypass

    On my 5455 the D+ engine running signal on my alternator sometimes works, sometimes not, before I knew you could just jumper it I was under the tractor a lot pushing the lower and raise nubs. I'm quite sure it would lower with the tractor off, you have to push really hard though.

    Quote Originally Posted by Cowabunga View Post
    I've no idea. The rams are obviously single acting. The control valve, where the solenoids are, must divert oil to the rams when activated one way, allow oil to flow through when not, and allow oil trapped in the rams to be dumped back to the sump when activated the other way and therefore lower the links. It is pretty well as simple as that.

    Perhaps you were not pressing the right way or hard enough on the solenoid ends?

  13. #43
    MF-ANDY
    Guest

    Re: mf3075 link arms bypass

    Quote Originally Posted by kmac View Post
    On my 5455 the D+ engine running signal on my alternator sometimes works, sometimes not, before I knew you could just jumper it I was under the tractor a lot pushing the lower and raise nubs. I'm quite sure it would lower with the tractor off, you have to push really hard though.
    cant be sure about 54 series but it is a different block than 3000 series

  14. #44
    cooper
    Guest

    Re: mf3075 link arms bypass

    got round to takeing the block off the side with selinoids on onpt problem is none of the capead bolds holding the solinoids or and other part will undo just keep rounding off any ideas on removeing them? im stuck if i carnt get in it

  15. #45
    cooper
    Guest

    Re: mf3075 link arms bypass

    it is the arms stuck up and still pumping as it loads the engine up and i droped the arms by leting oil out the rams and soon as i started it up again it went back up just the dam bolts stuck now supose new untit with selinoids would cost a small fourtune:cry:

  16. #46
    MF-ANDY
    Guest

    Re: mf3075 link arms bypass

    with a hammer and a drift give all the cap strews a belting on the end. use a good allen key socket and they should undo.

  17. #47
    cooper
    Guest

    Re: mf3075 link arms bypass

    Fixed it I took it to bits both selinoids off and the plunger comes out it turned out it was Jamed in lift by a small bit of metal probly from the broken hand brake very small but was enough to jam it. Gave it all a good clean out and back on and working again. Thanks for all the help glad I didn't start messing with the electrics

  18. #48
    hoff135
    Guest

    Re: mf3075 link arms bypass

    ill know where to look when it happens to mine now!

  19. #49
    cooper
    Guest

    Re: mf3075 link arms bypass

    easy job realy could have done it on the tractor had the bolts holding the lower selinoid on had come off easyer. i always seam to learn alot from these little jibs have a better understanding of how it all works now haveing done the pump then this its not as scary delving inside to take a look whats hapening next job is replace the handbrake as soon as i can spare the tractor for a few days and have a shed to park under instead of getting soaked outside . so farm in the last 2 months iv fitted new hy pump fixed this lift problem found the hand brake broken (still works ok lol) have managed to fix one of the 2 broken light switchs (contacts had moved in it) and replaced the other with a hd switch. just need new batterys a service a new air intake pot on the top of the bonnet as this one keep filling with water and will be somewhere near ok again :lolk: and iv not even though about the 2 holes that have apeared in the top of the wings and the rust patchs on the cab seams nothing is ever sorted 100%
    but hoppfully by spring will have a shed it will mostly fit under so some jobs can be done on rainy days.
    then theres the caseih 956 to set about

  20. #50
    Junior Member
    Join Date
    Jan 2016
    Location
    huddersfield
    Posts
    2

    Re: mf3075 link arms bypass

    Quote Originally Posted by hoff135 View Post
    Hi cooper, here is info on how the rear lift spool works. Might help.

    As you have probably ruled out electronics by pressing the ends of the solenoids, means your lacking hydraulic pressure. As far as i can see you need hydraulic pressure to lower as well as raise rear linkage. SO wondering if you could do a pressure test on the pipe which goes in at port 'p' on the diagram??? (need to ask the pro's first though!)

    If there was pressure then surely there must be a problem inside the spool block itself?????

    There is a no return valve to maintain pressure in the cylinders, i know very little about these things but this caught my attention????

    Im probably talking rubbish, buts its all i can think of by applying a bit of logic to the diagrams below

    good luck


    -----------------------------------------------------------------------

    -----------------------------------------------------------------------

    -----------------------------------------------------------------------
    I don't suppose you have the same diagram for the later type lift valve? like late 3120 perhaps on th61s?

    thanks
    dan

  21. #51
    Senior Member
    Join Date
    Feb 2013
    Location
    Co Down
    Posts
    428

    Re: mf3075 link arms bypass

    Hoff135 hasn't been on since Nov 2016........Maybe a poor chance he'll see your question......Jan 2013 since the last post on this thread.Maybe someone else will have what your after though.....

  22. #52
    Junior Member
    Join Date
    Jan 2016
    Location
    huddersfield
    Posts
    2

    Re: mf3075 link arms bypass

    Quote Originally Posted by agrimax View Post
    Hoff135 hasn't been on since Nov 2016........Maybe a poor chance he'll see your question......Jan 2013 since the last post on this thread.Maybe someone else will have what your after though.....
    Thanks,

    i had lost the middle rod out (well it had moved internally and i could not see it, i had convinced myself this newer valve didnt have 1 as i just could not find it. last washout of valve and it moved and i saw it, a while prodding and pokeing got the tiny thing out in the end then cleaned and refitted everything. all working as it should now.

    thanks.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •