The JLG 40F Boom Lift Dilemma

[OFF]

I'm not trying to take over the thread but I am new to the forum and can't make a new topic. I have a JLG Model 60F and was hoping to get some info (diagrams, manuals, etc) from anyone on here (OFF and ATCOEQUIP seems like you have the experience with these pieces of equipment).

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?

 

[pitt23]

OFF, the 60f has (3) PQ controllers (swing, lift, and travel) with no boots just levers into the control box.

 

[OFF]

OFF, the 60f has (3) PQ controllers (swing, lift, and travel) with no boots just levers into the control box.

You've got mail!

 

[willie59]

You've got mail!

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

 

[EMT]

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

 

[EMT]

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!

 

[OFF]

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.

 

[willie59]

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.

 

[EMT]

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.

 

[willie59]

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.

LoL, it's your world...we're just ridin' on the passenger side with the window down.

Well, did you get your problem figured out?

 

[EMT]

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.

 

[EMT]

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

 

[willie59]

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.

 

[EMT]

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?

 

[willie59]

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.

 

[EMT]

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?

 

[willie59]

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?

 

[icewater75074]

40f

I started talking about my JLG 40F in 3 other forums. I needed to post at least 3 times before I was allowed to post my own thread. Sorry for the inconvenience. Here are the issues. First JLG gives no support on the E or the F series. If you go to there Manual’s down load area they are not even listed. They do list some parts though. As for service they have not returned 1 of my phone calls. I did receive an email reply from them. It was a link to there dealer and service people. All of the places that were around me were rental places and only did in-house repairs on their own equipment. One place in VT said they would look at it but only when they had time. I asked him if he could tell me the hydraulic cable lengths from the boom back, as well as the size and type of hose needed. I also asked him about the cable length. He told me he had to look it up, and would give me a call back. He didn’t call me back. I know people are busy.

Here are my problems.

This 40F has been patched so many times. The wiring harness from the engine compartment half way up is original. It was then spliced with a similar type of cable (not a bad job). After that it was spliced with some 20 awg aluminum cable, then back to copper. Inside the panel half of it was bell wire. Insane!

The hydraulic lines look to be original. Deep cracks etc. No leaks though.

No brakes (maybe only needs pads)

Only reverse. (If I move the joystick to forward it still goes in reverse.)

I rebuilt the 3 joysticks. One of them had circuit board damage that I by passed. I switched them around to positions that I knew worked well and they all seem to work fine.


Here’s what I am looking for.

Wiring diagram
Hydraulic Diagram
What type of hydraulic line is needed and what manufacture do you think is best.
What is the correct inside diameter of the hoses in the boom?
What type of connectors do you think are best?
Should the wiring and hydraulic lines be lightly tye-wraped some how?
What is the thinnest hydraulic oil that can be used, and what brand do you recommend?
Anything related to lubing. I see the zert fittings but what about the turret, and the booms?

Please feel free to jump in. Any advice will be more than welcome.
So many questions so little time.

Thanks to all who had the patients to read through all of this.

Thanks again OD1 od@intersat.cc

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

 

[modern]

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.

 

[willie59]

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.