1. Thank you for visiting HeavyEquipmentForums.com! Our objective is to provide industry professionals a place to gather to exchange questions, answers and ideas. We welcome you to register using the "Register" icon at the top of the page. We'd appreciate any help you can offer in spreading the word of our new site. The more members that join, the bigger resource for all to enjoy. Thank you!
  2. ALL NEW MEMBERS READ THIS FIRST!! Thank you for joining Heavy Equipment Forums! If you are new to forums we communicate with "Threads", please search our threads to see if your topic may have already been answered and if not then click "Post New Thread" in the appropriate forum. This will allow all of our members to see your question and give you the best chance to be answered. After you've made a number of posts you will graduate to Full Member status where you'll see a few more privileges. Following these guidelines will help make this the best resource for heavy equipment on the net. Thanks for joining us and I hope you enjoy your stay!!

The JLG 40F Boom Lift Dilemma

Discussion in 'Other Construction/Demolition Equipment' started by od1, Sep 13, 2009.

  1. OFF

    OFF Senior Member

    Joined:
    Sep 30, 2009
    Messages:
    775
    Occupation:
    HD Mechanic/Shop Foreman
    Location:
    Alberta, Canada
    Welcome :)
    We'll do our best to help you out.
    I do not have a 60F manual, but I do have a fairly complete collection of diagrams & schematics as well as a bit of dead parts stock.
    What kind of controllers does your 60F have?
     
  2. pitt23

    pitt23 New Member

    Joined:
    Jan 8, 2010
    Messages:
    2
    Location:
    pittsburgh, pa
    OFF, the 60f has (3) PQ controllers (swing, lift, and travel) with no boots just levers into the control box.
     
  3. OFF

    OFF Senior Member

    Joined:
    Sep 30, 2009
    Messages:
    775
    Occupation:
    HD Mechanic/Shop Foreman
    Location:
    Alberta, Canada
    You've got mail! :D
     
  4. willie59

    willie59 Super Moderator

    Joined:
    Dec 21, 2008
    Messages:
    12,475
    Occupation:
    Service Manager
    Location:
    Knoxville TN

    LoL...somehow, you cheated! That was just too easy! :yup :lmao :drinkup
     
  5. EMT

    EMT Member

    Joined:
    Feb 2, 2010
    Messages:
    21
    Occupation:
    Business Owner,salesman,manager and babysitter
    Location:
    Denver,CO
    PLease Help!

    Hey fellas,
    I am working on a 40 f today and saw that you guys have quite a lot of knowledge of this beast.
    Well , my question is this. I've got no swing,lift, drive functions, from basket or platform.
    I do have steer,boom in/out, bucket tilt from both bucket and platform.
    I have just installed a new hyd pump, not sure if these functions worked before the pump or not.
    Any body have any suggestions or manuals around?
    :Banghead
     
  6. EMT

    EMT Member

    Joined:
    Feb 2, 2010
    Messages:
    21
    Occupation:
    Business Owner,salesman,manager and babysitter
    Location:
    Denver,CO
    Oh another thing,
    I have checked psi and all is good.
    I have power at the dump valves and power at the controll coils.
    I can manually make the unit do all the functions by pushing in on the valves and twisting them in several rotations. But I need control from the switches.
    I think i need a bigger hammer!
     
  7. OFF

    OFF Senior Member

    Joined:
    Sep 30, 2009
    Messages:
    775
    Occupation:
    HD Mechanic/Shop Foreman
    Location:
    Alberta, Canada
    Things that make you go Hmmmmmmmm.

    My first guess would have been the relay (solenoid) powering the dump valve for the porportional functions, but being able to operate the functions manually rules that out.

    Run a volt meter to terminals #13 & #14 in the main control box, put it on basket control, ignition on, foot on deadman, and operate the drive controller.
    As soon as you move off center you should see approx. 6 volts. Moving one direction the voltage should go higher that 6, the other direction the voltage will go lower than 6. Let us know what yours says.

    Terminals in the box are arranged starting in the top upper left corner and working down each row.
     
  8. willie59

    willie59 Super Moderator

    Joined:
    Dec 21, 2008
    Messages:
    12,475
    Occupation:
    Service Manager
    Location:
    Knoxville TN
    Another thing you should check is to make sure terminal #24 at platform controls is making a good ground/earth. #24 is the common ground for the proportional controls. If it's not making a good ground, all three proportional functions won't operate.
     
  9. EMT

    EMT Member

    Joined:
    Feb 2, 2010
    Messages:
    21
    Occupation:
    Business Owner,salesman,manager and babysitter
    Location:
    Denver,CO
    Man, im glad I found you guys. I am constantly diagnosing problems with a lot of different kinds of equipment. Everything from dirt moving, material handling, highreach man lifts, to trucks, trailers, generators, air compressors and hyd attachments. Quite a lot of books, manuals and hard knox experience.
    You Guys are the Knights of Equipment and I am your page.
    Thank you for the info.
     
  10. willie59

    willie59 Super Moderator

    Joined:
    Dec 21, 2008
    Messages:
    12,475
    Occupation:
    Service Manager
    Location:
    Knoxville TN
    LoL, it's your world...we're just ridin' on the passenger side with the window down. :D :cool:

    Well, did you get your problem figured out?
     
  11. EMT

    EMT Member

    Joined:
    Feb 2, 2010
    Messages:
    21
    Occupation:
    Business Owner,salesman,manager and babysitter
    Location:
    Denver,CO
    still working on the diagnosis( I have turned it into a hands on class for the other techs). After chasing gremlins in the electrical harness, I had to remind the techs to KISS(keep it simple stupid) the beast. We found there is 12v to the control valves and dump valves. The dump valve for the 3 functions(swing, lift, drive)is working but not properly(its not moving enough and you can push it by hand, its weak) so I advised them to swapp the dump valves (the good one with the other is in question) we will see what happens. Then check the physical function of the controll coils on the 3 function valves.
    Why do techs always want to do the "drive by diagnose" and replace parts? I am trying to remove "assumption" and "probably" out of there vocabulary.
    I will let you know the outcome.
     
  12. EMT

    EMT Member

    Joined:
    Feb 2, 2010
    Messages:
    21
    Occupation:
    Business Owner,salesman,manager and babysitter
    Location:
    Denver,CO
    ok, we got the fix on the no swing,lift, drive problem. The dump valve was not closing all the way and under psi it would go back to tank every time. Thank you guys for setting on the right track. Now we have to find a valve other than jlg. They are pretty proud of there parts
     
  13. willie59

    willie59 Super Moderator

    Joined:
    Dec 21, 2008
    Messages:
    12,475
    Occupation:
    Service Manager
    Location:
    Knoxville TN
    Did you take the faulty dump valve apart and try to determine what's keeping the spool from shifting fully? Just wondering why you have to replace the dump valve. I can't remember on the 40F, but a lot of the later JLG machines have the main relief valve in the same valve body as the dump valve.
     
  14. EMT

    EMT Member

    Joined:
    Feb 2, 2010
    Messages:
    21
    Occupation:
    Business Owner,salesman,manager and babysitter
    Location:
    Denver,CO
    Oh yea, the dump valve had a contaminant in it. We cleaned it out and put it back. All is well.
    The reason I wanted to replace it is that the movement back and forth is weak. You dont think I should replace it?
     
  15. willie59

    willie59 Super Moderator

    Joined:
    Dec 21, 2008
    Messages:
    12,475
    Occupation:
    Service Manager
    Location:
    Knoxville TN
    Well, I'm trying to understand what you mean by the movement back and forth is weak. Do you mean the solenoid is slow to shift valve spool and it releases slowly as well? Just not sure what you mean. ;)
     
  16. EMT

    EMT Member

    Joined:
    Feb 2, 2010
    Messages:
    21
    Occupation:
    Business Owner,salesman,manager and babysitter
    Location:
    Denver,CO
    OK, try this. when you remove the valve from valve block, actuate the valve by putting the solenoid back on the valve, actuate the function from lower control box, the the inside of the valve stem moves up and down. The part that moves up and down inside the stem can be pushed in manually(pocket screwdriver) reguardless of position. in other words very littel psi can open the valve when it should be closed. Which tells me the valve is bad. What do you think?
     
  17. willie59

    willie59 Super Moderator

    Joined:
    Dec 21, 2008
    Messages:
    12,475
    Occupation:
    Service Manager
    Location:
    Knoxville TN
    It's been so long since I've worked on a 40F, I just can't remember what the dump valve components are like on one to follow along with ya. Maybe off has a parts diagram for one. Is there anyway you could make some pics of the components?
     
  18. icewater75074

    icewater75074 Member

    Joined:
    Jan 28, 2010
    Messages:
    17
    Occupation:
    Field Tech.VOLVO Equip.
    Location:
    Texas
    40f

    I have the schematics you need on a disc, I can e-mail them to you or scan them and fax them, I have the disc from one of my certification classes.
    Just let me know if you still need them. Also, you would be better off in the longrun to R&R the harness, you can get the cable from aftermarket suppliers, the numerous splices you mentioned especially going from copper to aluminum will reak havoc on amperage. These old units aren't as sensitive as the new ones to voltage/amperage drop and spike, but you can get some ghost functions from the bad grounds that can occur from these splices.
    Have a good day.:bash
     
  19. modern

    modern New Member

    Joined:
    Feb 15, 2010
    Messages:
    3
    Location:
    Fresno, CA
    Sounds like our Manlift 40FR. My maintenance shop has asked me to searchout and find electrical and hydraulic schematics as the unit will not go into second gear. We did have a repair shop do major work on this unit a few years back. Everything worked fine until recently. Let me know if anyone comes across these schematics/manuals.
     
  20. willie59

    willie59 Super Moderator

    Joined:
    Dec 21, 2008
    Messages:
    12,475
    Occupation:
    Service Manager
    Location:
    Knoxville TN
    Welcome to the forum modern. :usa

    I wonder if your 40FR is the same as the 40F. Off emailed me the electrical schematics on the 40F.

    You might have a problem with the mercury switch on main boom. It cuts out the hi drive circuit when boom is elevated, it also cuts out the hi throttle. A malfunction of the mercury switch would affect both these operations.