The JLG 40F Boom Lift Dilemma

[willie59]

Wow! Thank you! I received the manuals and a quick look shows a lot of useful information.
Thanks also for your reply especially for pointing out that the fly and mid-section do not have to be separated. As you can tell I'm trying to get all my ducks in a row before beginning. Especially where to park the F40 so I will be able to reach where needed with a forklift.
I'd like to keep you posted - it may be a while before I begin.
Thanks again for all the help!

LoL, well, I didn't say that the mid and fly doesn't have to be separated. I said I think it doesn't have to. It's been a long time since I've worked on a 40F, a lot of junk cluttering up my memory.

 

[superdaveweld]

knock on wood

I knock on wood that my telescope in not leaking yet. Thanks to all of your fellows help with wiring diagrams I just about have the eletrical issues solved. I have moved on to the brakes. I disassembled one of the cyls for the drive brakes and found many pieces of disk springs. I have been scratching my head and setting here all day with a caliper making measurements. Does any one know how many springs these cyl's take or the stack orientation? The only way that makes sense to me is a series parallel stack. Jlg actually has cyl.s available but they are perty proud of them also $541.00 ea. In another note does anyone know if the swing brake is the same as the travel brakes, looks inentical?

 

[willie59]

Can't remember to be certain, but I'm thinking the brake cylinders had belleville washers. And it seems I remember there was a trick to taking those things apart and putting them back together. I don't think the brake for the swing uses the same type components. You might send a PM to OFF, he might have a better memory of these components.

 

[OFF]

I used to stack the washers kinda like this - )()()()()()()( to get the best spring effect out of them. One thing to rememeber is they are spring applied/hydraulicly released which is backwards to most brake thinking. I found the best way to adjust them was to get a co-worker to bring the machine up against 2 good chock-blocks in drive, then while the brakes are released (still in drive) tighten the pad adjusting screw till there was minimal clearence between the pads and rotor. Like maybe 0.010 to 0.020. Just enough to 'feel" some movement. Then release the drive controller and you should have maximum clamping force. Brakes on the 40F were not as good as the multi-disc wet type found on later models, but they worked. We got into the habit of checking brake adjustment on every service.

 

[dblazer]

First let me say how much I appreciate this forum for the help I've received. I have the boom of the JLG 40F disassembled. I hope to be able to help anyone else with this. There are some gotchas and knowing the balance point of the boom parts may help. I see that the clevis eye of the cylinder has to be cut off in order to remove the shaft seal assembly. Has anyone made a fixture to re-weld this? If not I'll make one and it'll be available.
I'll need some JLG parts - cylinder seals and wear pads also I'm replacing the boom's wire and hydraulic lines. ATCOEQUIP are you a JLG distributor?
And a point of etiquette - is it OK to continue posting to this thread or should I start a new thread?
- thanks

 

[willie59]

And a point of etiquette - is it OK to continue posting to this thread or should I start a new thread?
- thanks

Well, IMO, I think you should post it on this thread. This thread has become a resource that's loaded with JLG 40F information that is easy for other readers to locate, especially those with a 40F.

BTW, you don't cut the rod eye off to replace seals, you take the cylinder apart, then remove a nut that retains the rod piston on the rod, then the cylinder gland (head) slips of the cylinder rod. As far as I'm concerned, whenever I go through the trouble of taking a boom apart to repair a leak from the cylinder then I'm going to replace every seal in that cylinder because I don't want to have to go back in there for a while.

In my case with the parts, I have a local Parker Hannefin seal distributor and they typically can provide me with most any type seal. Hoses I get made at local hose shop. The wire cable, that's a different story. First of all, it ain't cheap. Nothing with copper in it is cheap anymore. But in my experience, after making many searches for suppliers of cable, it seems JLG will either match their price, or many times JLG is cheaper. I have a theory this is because JLG purchases miles of wire cable in a years time to build machines so they probably get it at a very good quantity price. The thing is, you have to use a cable that is designed to flex for many cycles. Typical SO, SEO, or Tray cable won't work in that application.

Am I a distributor? Nope, just someone who has been working on them for years. I haven't worked on every model they have made, but a good many of them. As for parts, it's generally best to work with someone close to you. That is, if you have a good dealer that's a pleasure (not a chore) to work with. Most equipment rental stores are JLG distributors. If you don't have a good distributor, the outfit I buy parts from is in Shippensburg PA, not far from JLG. I've been buying parts from them for years and Eric and Jeremy knows the machines and parts well. 1-888-321-3217

 

[arjaytee]

40F Hydraulic Question

Hi everyone,
It's been a while since I posted anything, but I have a question about hydraulics on my 40F machine. I installed a new pump and coupling (old pump was leaking badly at input shaft seal). All machine functions seem to be working correctly, but the engine is loaded with all controls in neutral position. When I shut the engine off, it sounds like a rush of hydraulic oil into the tank. I don't have a lot of hydraulic experience, but I'm wondering if there could be air somewhere in the system keeping a valve in the wrong position, from when I had the hyd. lines off for pump replacement. I removed the hyd. tank for easier access to the pump and quite a bit of oil drained from the lines that were removed from the tank. That's what has me wondering if there could be air in the system and what I have to do to purge it.
Something else I could use, would be the maintenance manuals for this machine. I have the parts manuals which Atcoequip was so generous in supplying. Thanks for any assistance you can provide.

 

[OFF]

You've got mail Arjaytee

I can't see it being air in the system, sounds more like maybe a hose ended up in the wrong place when you re-installed the tank. The service manual has hydraulic schematics, they should help you track it down.

 

[arjaytee]

40F Hydraulics

Thanks OFF for the service manuals you sent so quickly. I'll go through it and see if I've got something routed the wrong way.

 

[superdaveweld]

40f brakes

I used to stack the washers kinda like this - )()()()()()()( to get the best spring effect out of them. One thing to rememeber is they are spring applied/hydraulicly released which is backwards to most brake thinking. I found the best way to adjust them was to get a co-worker to bring the machine up against 2 good chock-blocks in drive, then while the brakes are released (still in drive) tighten the pad adjusting screw till there was minimal clearence between the pads and rotor. Like maybe 0.010 to 0.020. Just enough to 'feel" some movement. Then release the drive controller and you should have maximum clamping force. Brakes on the 40F were not as good as the multi-disc wet type found on later models, but they worked. We got into the habit of checking brake adjustment on every service.

Thanks for the info took both drive brakes and swing brake apart. It looks like the springs are stacked the way you describe at least in the swing brake, they were in good enough shape to see stacking. That was before I had to heat them for disassembly. I will replace all springs and seals. Jlg wanted $ 550.00 ea so I am having them bored and sleaved at a machine shop. parts will be finished next week sometime. I am now tring to locate a reasonably price dule crossover relief lock valve combo as the one for the basket rotate is missing. Do you know what the relief for rotate is supposed to be? I could not find the spec. in the manual, I am guessing under 1500 psi. Correct me If I am wrong but this means that the lock valve you would use would have to be set less than our relief, like 800 to 1000psi ? I am tring to get my head around how they incorprated both of these togeather and made the work. In my thinking the lock valve is supplied by the control valve unless you broke a hose in which case where is the basket really going to anyway? I want to fix this safe and right though. Do you have any ideas on valving?

 

[willie59]

I am now tring to locate a reasonably price dule crossover relief lock valve combo as the one for the basket rotate is missing. Do you know what the relief for rotate is supposed to be? I could not find the spec. in the manual, I am guessing under 1500 psi. Correct me If I am wrong but this means that the lock valve you would use would have to be set less than our relief, like 800 to 1000psi ? I am tring to get my head around how they incorprated both of these togeather and made the work. In my thinking the lock valve is supplied by the control valve unless you broke a hose in which case where is the basket really going to anyway? I want to fix this safe and right though. Do you have any ideas on valving?

I think your describing using a holding valve for a hyd component, such as a cylinder to prevent drift or cylinder dropping in case of failed hose. The basket rotate motor really doesn't need holding valves, but it does need crossover reliefs in the circuit. The main reason would be if you were to hit something with the basket, like when your telescoping out. If you were encounter an obstruction with the platform, the crossover relief would allow the basket to rotate instead of damage or break basket components. I can't remember what the relief setting should be. You might find one at a reasonable price from Bailey Hydraulic, http://baileynet.com/index.php

 

[OFF]

I am now tring to locate a reasonably price dule crossover relief lock valve combo as the one for the basket rotate is missing. Do you have any ideas on valving?

Better than that.......I have a new one sitting on the shelf collecting dust.
JLG #4640154 I love getting rid of dead stock

 

[superdaveweld]

crossover relief got my attention!

Wow, ok got my attention now. How much is that dude worth to you? I can buy a new prince crossover relief for just under $70.00 but from what I can tell the one jlg used incorprated load locks as well.

 

[superdaveweld]

hyd parts

I think your describing using a holding valve for a hyd component, such as a cylinder to prevent drift or cylinder dropping in case of failed hose. The basket rotate motor really doesn't need holding valves, but it does need crossover reliefs in the circuit. The main reason would be if you were to hit something with the basket, like when your telescoping out. If you were encounter an obstruction with the platform, the crossover relief would allow the basket to rotate instead of damage or break basket components. I can't remember what the relief setting should be. You might find one at a reasonable price from Bailey Hydraulic, http://baileynet.com/index.php

Good site for hydraulic parts. another one if you are interested is www.surpluscenter.com they have a little of everything.

 

[dblazer]

JLG 40F boom leak repair

BTW, you don't cut the rod eye off to replace seals, you take the cylinder apart, then remove a nut that retains the rod piston on the rod, then the cylinder gland (head) slips of the cylinder rod.

Thanks ATCO for the detailed post, all the valuable information and the heads-up. My tele cylinder does not have a nut but I took another look at the welded tubes on the "nut" end of the cylinder rod and found pipe wrench teeth marks and so assumed (correctly) that the inside section was threaded. All is apart now and you were right - the fly can stay in the midsection.

 

[willie59]

BTW, you don't cut the rod eye off to replace seals, you take the cylinder apart, then remove a nut that retains the rod piston on the rod, then the cylinder gland (head) slips of the cylinder rod.

Thanks ATCO for the detailed post, all the valuable information and the heads-up. My tele cylinder does not have a nut but I took another look at the welded tubes on the "nut" end of the cylinder rod and found pipe wrench teeth marks and so assumed (correctly) that the inside section was threaded. All is apart now and you were right - the fly can stay in the midsection.

Rock on dude!

 

[demodude]

Hello Guys, I'm new to the site and have a 40f. It keeps on running and is a great help.
I hope I'm jumping in properly here but I'm having 2 electrical problems in the basket.
I have Bertea valves with the Wisc. V-4. I have read all of the posts on here and see that
this is the greatest forum. Thanks in advance for any help anyone can give us.

 

[willie59]

Hello Guys, I'm new to the site and have a 40f. It keeps on running and is a great help.
I hope I'm jumping in properly here but I'm having 2 electrical problems in the basket.
I have Bertea valves with the Wisc. V-4. I have read all of the posts on here and see that
this is the greatest forum. Thanks in advance for any help anyone can give us.

Welcome to the forum demodude. :usa

 

[superdaveweld]

welcome demodude. I am a new member here to. The guys here are an encylopedia of info on these old machines. I just about have my electrical problems worked out thanks in large to a couple of the fellas here. I was really going nuts, wiring not my strong point, but wiring diagrams where a great help. I think off can probably assist you with wiring issues good luck.

 

[OFF]

Welcome Demodude

I sent you a set of Bertea wiring schematics for your 40F, hopefully they help you out.
What kind of basket wiring problems are you having?