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JLG 40HA won't idle up after depressing the foot switch.
- Thread starter ksp
- Start date
Got a little time today so looked in botttom control box and the black/red wire is not connected to anything. The red wire for horn power was not connected so I put it on the circuit breaker but no horn so will have to look into that. The one thing I did notice is that the #1and #2 points on the terminal strip should have had a diode? in line but only the #2 had it so don't know if that would do anything or not. That is as far as I got.
The platform control cover is going to be dificult to remove as the screws are not coming out. Those stupid tin nuts are striped and won't let the screw back out. The PO bent the crap out of the basket and the cover doesn't fit right anymore. Anyway I will have to get it off and look around under the hood.
Also I confirmed that the boom arm level switch worked b/c it would slow down after I got so high in the air but the tower was able to go all the way up without slowing the speed down and I could not locate it. Do you know where it is located?
The platform control cover is going to be dificult to remove as the screws are not coming out. Those stupid tin nuts are striped and won't let the screw back out. The PO bent the crap out of the basket and the cover doesn't fit right anymore. Anyway I will have to get it off and look around under the hood.
Also I confirmed that the boom arm level switch worked b/c it would slow down after I got so high in the air but the tower was able to go all the way up without slowing the speed down and I could not locate it. Do you know where it is located?
willie59
Administrator
Well ksp, I've had a little time to noodle through the electrical diagrams and you've taken me to school. I haven't worked on the hyd control version of the 40HA. It seems they wire things a little differently depending on model version as well as engine used. I reckon it's good for an old fool to go to school now and again. :yup 
If I'm reading it correctly, your mid engine throttle is being activated by the dump valve circuit from the platform. When you step on the foot switch, it powers up the yellow wire circuit to provide power for electrical switches and controls at the platform. The last switch in the circuit is the steer switch. That's where the red wire of the 16/12 cable connects to yellow foot switch activated circuit. At the lower control box, the red wire connects to terminal #2 of the terminal strip. You should then have a wire that goes from terminal 2 to terminal 86 of the R15 dump valve relay. That powers up the relay to send voltage to the dump valve and enable the hyd operations. Back at terminal #2, voltage from the red dump valve wire is sent through the diode, then through a yellow wire to terminal #1 on R1 relay. I can't really remember what all functions the R1 relay controls as it's a multiple contact and terminal relay, but it appears to me that the yellow wire at terminal 1 is the Normally Closed contact with terminal 9 of the R1 relay. Power would go from 1 to 9, then through orn/grn wire connected to terminal 9, then orn/grn wire goes to terminal 86 of R13 idle relay, which powers up the coil on the R13 relay. When this happens, it connects terminal 30 to terminal 87 of the relay. This sends voltage from terminal 30 to the yellow wire that's connected to terminal 87 of R13 relay. That yellow wire goes to terminal 1 of the E201 Prescison Governor control box and powers up the mid engine speed control, which is that rev up rpm you get during boom operations. Hi engine speed for drive is achieved when R14 relay sends voltage to terminal 7 of the E201 governor controller. That's the way I'm seeing it on the diagrams.
If I'm reading it correctly, your mid engine throttle is being activated by the dump valve circuit from the platform. When you step on the foot switch, it powers up the yellow wire circuit to provide power for electrical switches and controls at the platform. The last switch in the circuit is the steer switch. That's where the red wire of the 16/12 cable connects to yellow foot switch activated circuit. At the lower control box, the red wire connects to terminal #2 of the terminal strip. You should then have a wire that goes from terminal 2 to terminal 86 of the R15 dump valve relay. That powers up the relay to send voltage to the dump valve and enable the hyd operations. Back at terminal #2, voltage from the red dump valve wire is sent through the diode, then through a yellow wire to terminal #1 on R1 relay. I can't really remember what all functions the R1 relay controls as it's a multiple contact and terminal relay, but it appears to me that the yellow wire at terminal 1 is the Normally Closed contact with terminal 9 of the R1 relay. Power would go from 1 to 9, then through orn/grn wire connected to terminal 9, then orn/grn wire goes to terminal 86 of R13 idle relay, which powers up the coil on the R13 relay. When this happens, it connects terminal 30 to terminal 87 of the relay. This sends voltage from terminal 30 to the yellow wire that's connected to terminal 87 of R13 relay. That yellow wire goes to terminal 1 of the E201 Prescison Governor control box and powers up the mid engine speed control, which is that rev up rpm you get during boom operations. Hi engine speed for drive is achieved when R14 relay sends voltage to terminal 7 of the E201 governor controller. That's the way I'm seeing it on the diagrams.
willie59
Administrator
Thanks for your help. Got to find the tower lift limit switch and fix that so it kicks down to low speed when raised and a couple other small problems but I'm getting the bugs out. When I was messing with it yesterday I did notice that sometimes when moving the platform/ground switch that it would not actuate the precision gov. Usually when I switch it the gov will pull the throttle rod a bit at first. I wonder if I have a switch problem or a sticky relay that doesn't operat all the time.
Thanks again.
Thanks again.
willie59
Administrator
If you look at section 3-2 in the parts book, it shows you where the cutout switches are. I'm thinking the tower boom cutout switch is underneath the cylinder that raises the lower tower boom.
Could be any number of things causing your intermitent throttle problem, toggle switch being one of them. Just don't use cheap toggle switches as replacements. You can get a good price on original type toggles used on your machine from Hindley Electronics. You simply give them the JLG part number from the parts book and they'll send you the correct switch.
http://www.hindleyelectronics.com/
Be sure and look closely at the 16/12 cable going down the boom, especially in the area around the basket pivot points. Look for any damage spots in the cable that would cause problems with wiring.
Could be any number of things causing your intermitent throttle problem, toggle switch being one of them. Just don't use cheap toggle switches as replacements. You can get a good price on original type toggles used on your machine from Hindley Electronics. You simply give them the JLG part number from the parts book and they'll send you the correct switch.
http://www.hindleyelectronics.com/
Be sure and look closely at the 16/12 cable going down the boom, especially in the area around the basket pivot points. Look for any damage spots in the cable that would cause problems with wiring.
willie59
Administrator
The cable. Well, that's a good question. It depends on how cheap (won't last long) one wants to do it, or if they want it to last. If you don't use a cable that is designed for constant flexing (no, typical SO or SJ cable is not), the bending of the wires in the conductors will cause the wires to break, and the insulators of the individual conductors are constantly rubbing against each other. Improper cable with have failure of the insulating jacket of the conductors from the friction of rubbing each other, electrical shorts and all sorts of goofy things happen. You can find the proper cable from aftermarket sources, but it still ain't cheap. In my experience, getting it from JLG is equal to and sometimes a better price than other sources. I'm thinking it's because JLG purchases thousands of feet of this cable for production of machines, so they probably purchase it at a good quantity discount and are able to keep replacement prices comparable to other suppliers.
As for the tower boom speed cutout switch, I'm sure it originally had one. JLG doesn't allow any machine to go in hi speed drive with any boom raised, too dangerous.
As for the tower boom speed cutout switch, I'm sure it originally had one. JLG doesn't allow any machine to go in hi speed drive with any boom raised, too dangerous.
Ok, I'll look into JLG for wire.
I have been looking for the hyd oil filter,,,,,where is that located? Is it the schroder filter on the side of the pump when opening the side door? I thought it might be like a regular oil filter somewhere.
I have been looking for the hyd oil filter,,,,,where is that located? Is it the schroder filter on the side of the pump when opening the side door? I thought it might be like a regular oil filter somewhere.
willie59
Administrator
The filter located near the pumps is a filter for the charge pump of the drive pumps. The main hyd filter is located in the hyd tank. On top of the tank is a large round casting that has piping going to it. That's the return to tank pipe. There are 4 hex head bolts that hold a cap on that casting. Remove those bolts and remove the cap plate, hyd filter is in there. You can get the filter from aftermarket suppliers such as Wix, Hastings, etc.
Duh, I should have looked there!
After looking at the filter housing, I saw that there is a guage on that housing which is broke. How important is that and what would it tell me? I also saw that there is a return suction filter in the tank but that is priced at $200 or better. Does the guage register vacum in the tank or something?
Man, I really appreciate you taking the time to explain the functioning of this unit to me. It's like having a mechanic on retainer!!!!
After looking at the filter housing, I saw that there is a guage on that housing which is broke. How important is that and what would it tell me? I also saw that there is a return suction filter in the tank but that is priced at $200 or better. Does the guage register vacum in the tank or something?
Man, I really appreciate you taking the time to explain the functioning of this unit to me. It's like having a mechanic on retainer!!!!
willie59
Administrator
Page 2-90 of the parts book shows the hyd tank return filter assembly. The gauge on the return filter housing reads pressure. If the filter starts getting clogged from debris, the pressure in the return line would start to rise. The needle on the gauge indicates the pressure in the return line. The gauge is useful for monitoring condition of the filter.
Are you saying the filter element for the hyd return in the tank is $200? That's outragious for an element. It should be a Wix #51434. It won't come with a new o-ring for the lid, but in most cases you can re-use your o-ring unless it's in really bad shape.
There's a pressure filter at the drive pump as well, it's more of a strainer type filter, and I think the element for it is a little spendy. It should have a restriction indicator on it as well, a little different than the gauge on the return line. The purpose of that filter is to protect the variable piston pump for the drive circuit from any debris that would come from the charge pump, whether from normal component wear of the charge pump or component failure. Piston pumps are picky about debris floating through them.
Are you saying the filter element for the hyd return in the tank is $200? That's outragious for an element. It should be a Wix #51434. It won't come with a new o-ring for the lid, but in most cases you can re-use your o-ring unless it's in really bad shape.
There's a pressure filter at the drive pump as well, it's more of a strainer type filter, and I think the element for it is a little spendy. It should have a restriction indicator on it as well, a little different than the gauge on the return line. The purpose of that filter is to protect the variable piston pump for the drive circuit from any debris that would come from the charge pump, whether from normal component wear of the charge pump or component failure. Piston pumps are picky about debris floating through them.
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No not that filter. There is another filter in the bottom of the tank acccording tot he parts diagram which is on the suction line. According to an online source they wanted around $200 for that filter.
Good just what I needed was that Wix part #. I have an outlet for those, Thanks.
Good just what I needed was that Wix part #. I have an outlet for those, Thanks.
willie59
Administrator
Oh, that filter. It's actually just a big screen filter to keep large pieces of debris from getting to the pumps and causing damage to them. You would have to drain the oil out of the tank to access that one. They typically don't need any kind of service unless you know your machine has some kind of past major component failure. In order for that screen strainer to get clogged, it would take a substantial amount of debris in the tank, which would mean you probably have a bigger problem than a clogged strainer screen. If, perchance, you just wanted to be thorough with your machine, and had the means to drain the tank and contain the oil in clean containers, it wouldn't be a bad idea to drain the tank and get a look in there. Any component failure particles from past or recent failures are going to be at the bottom of the tank. I've even seen pieces of cylinder seals, o-rings, and the vererable teflon tape stuck up against the strainer screen.
Oh I see, I thought it was a replaceable filter of a cheaper nature but I know what you are talking about. I'm going to check out that wix filter and see what comes with it and go from there. It appears as though the return filter cap has never been off unless it has been repainted. I had to replace about 30 gallons of hyd oil last year due to busted lines and a bad cylinder so just want to get a new filter in there.
That wix number was just the one. Got it replaced with no problem. Could a guy use any fluid guage in there? If so what would the range be for the guage movement? My guage is broke and I can't read it to tell what I need in there. I assume it reads a positive pressure and so what would be considered a normal range?
willie59
Administrator
The gauge is meant to indicate when there is restiction by clogged filter, when the needle goes into the red range, but I don't know what psi pressure that is. It depends at what pressure JLG has set the by-pass valve in the filter lid. Don't know what that pressure is. Have you priced a new gauge from your JLG parts supplier? If nothing else, you should change your engine oil and filters every 150 to 200 hrs. If you change you hyd filter when your doing you engine filters, I don't think you're going to have an issue with clogged hyd filter so gauge woudn't matter that much.
I have gotten some parts from GCIron.com and they list that part for $42.18. Is there a better place to get JLG parts at a discount. The dealers around here have not been helpfull so I see no need for me to pay their inflated prices for parts.
But you are right, it would be just as easy to replace that filter when doing engine oil changes. I don't use the lift a lot so I have been changing oil once a year whether it needs it or not ;-)
But you are right, it would be just as easy to replace that filter when doing engine oil changes. I don't use the lift a lot so I have been changing oil once a year whether it needs it or not ;-)
willie59
Administrator
Well, don't know if there is such a thing as "discount" JLG parts, at least not for parts that come from JLG. I've been dealing with one company in Shippensburb PA, about 30 miles from JLG, for many years now. They started out as husband/wife owned company, husband used to work for JLG. A couple of years ago, they got bought out by Best Line Equipment, a large Bobcat dealer and rental company in State College PA. I still call them for parts because I have been calling Eric and Jeremy for parts for years now, and they are close to JLG, they know the system well. I don't know if their price would be any better but you could give them a call, 888-321-3217. If I need electrical parts, switches or controllers, I call Hindley in Ohio.