I acquired a new to me JLG 33RTS to use around the house and farm. It is a 1996 Model with the Ford Gas Engine. Its a 4x4x2. I noticed the platform raises and lowers well but it has a problem moving its slow and sometimes doesn't move at all but seams like its trying. First Issue Precision Governor e-301 controller is not working I have done all troubleshooting and opened the controller a few resistors and a transistor is toast. Does any one know who repairs these a new one at 450 seams high. If anyone has a scematic I could try a repair my self with a little information on the components that are burned. Next one Hydraulic motor is broken off a torque hub. The aluminum mounting plate snapped. JLG wants 1500 for these motors does any one else have a source for a 2.48 Piston motor for a JLG? Thanks In advance
Call Hindley Electronics about your Precision Governor. > https://www.hindleyelectronics.com/ About the drive motor, a good hydraulic pump/motor shop should be able to come up with a replacement case, will likely require motor disassembly to repair case, will be some cost involved there unless you do it yourself. If you don't know a pump/motor shop, they may be a good distance from you, but Ron at Fluid Power International has obtained a number of replacement motors for JLG machines for me. > www.fpihydraulics.com
Hindley is upgrading their test engine, said it may be a few months before they could even look at it. I will check out local hydraulic shops. Found out tonight I have one wheel drive, other three don't turn with power. I am not sure to start at the pump or the hubs, or motors? What do you think. The one that does drive drives fairly well just struggles to move the entire machine. Manual says to put a pressure gauge to to pump and read charge pressure I know its a Sunstrand 2.8 pump but not sure what kind of gauge and fitting to get nore what port to hook too. Thanks for all the help.
Ok, you had to start throwing knuckle balls. I do declare, don't think I've ever worked on one that had three drives down and only one working, not sure how to go about this. If it drives at all, I can't see it being a problem with the charge pump, also, the pressure from the charge pump releases the brakes, if charge pump pressure was down, don't think the machine would do much moving. But what to do. Have to ask, has someone flipped the drive disconnect plate on the faulty three drives? On the outside of each torque hub is a plate. You should see a teet sticking out on that plate. If the plate is flipped over (with teet sticking in) the hub is disconnected.
I had to flip the hubs to get it home and I did flip them back. If I put a block in front of any of the three wheels that don't turn it will spin the one that does work. The one driving it will move the machine but only when in high wheel speed mode. Again remember the governor doesn't work either. Also one of the three drive wheels not working is due to the drive motor broke off the hub. makes me want to start with the hubs locked in disconnected but i have no reason to think so.
Ok, A little more troubleshooting. It turns out the three other drive motors do work, acts like it looks for the wheel with the least traction. However it will move the machine as long as you are on flat hard ground, as soon as you try to go over a bump or ledge or slippery ground it will start spinning one or two tires. Usually only one wheel has full power. Put the lift on jack stands and still get one tire turning with power if i manually try to rotate another tire it will start spinning usually stopping the one that was spinning. This will happen at any of the three drives that are still connected. Since the front left motor broke from the hub is it possible its turning to easily and not allowing the system to operate at pressure? Should I pull the motor and cap the lines? (until it can be repaired) What other areas should I look at? Thanks again
Hmm, multiple questions. First of all, does it have an articulating steer axle? If not, even though it's 4wd, it will have traction difficulty on rough terrain. Additionally, whether it has articulated axle or no, the 4wd isn't comparable to the 4wd action we're accustomed to with, say, a 4wd pickup truck, it's just not the same. In the realm of scissor lifts, many models/designs are what we call "slab machine", meaning, they're made for use on hard/flat surface, like a concrete slab. But those are useless for something as mildly uneven as a gravel lot. So mfgs offer the RT machines such as yours, they will work on terrain that a slab machine won't. Having said all this, the drive on your machine is paired up as front axle, left/right motor, and a power divider valve to control flow to those two motors, and then the rear axle, left/right motor, and another power divider valve for those two motors. The main function of the power divider valves is to allow changing flow to the motors when turning the machine as one wheel will be turning faster than its mate while turning. The power divider valve adjusts flow to the two motors to allow this to happen without either scuffing a tire or forcing it to hop. The power divider valves may also play a role when a wheel looses traction, but to what degree I just don't know and it's not clear on the JLG diagram. As to whether you can disconnect the lines going to the busted motor and cap them, I don't know what the result would be, never had to try that, not sure how the power divider valve would react. Have you contacted Ron at Fluid Power about having that broken case replaced? Or is it possible to have the broken case welded and repaired?
No it does not have the articulating axle. Your explanation helped me better understand the drive system. I am used to skid loaders and other 4x4 machines but this makes sense. I would venture to say then it operated well without a governor and one broken motor. With the 4th motor it may be able to traverse the 3inch ledge in to the shop? I have not contacted Ron yet i will do so as you suggested. I need to pull the motor and see if the case can be repaired.(welded) Will this drain the hydraulic system if i disconnect the motor? Thanks again for your help and patience.
It won't drain the system removing the two big hoses going to the motor, but they will leak some oil. The small hose is the case drain line, it can continue to leak oil. It would be best to have the proper plugs to put in the hose fittings. I'm guessing those fitting are JIC, don't recall JLG using ORFS fittings on those machines. If the hose lines take a 1 1/4" wrench, there's #12 JIC. If the case drain takes an 11/16" or 3/4" wrench, that would be #6 JIC. Any hyd hose shop can supply you with JIC plugs and caps. If it's just the mounting ears broken off the motor, it's very possible that a good welder can repair it. If not, look for an ID tag on the motor and get the numbers off of the tag, also take a few.digital pics of the motor, shoot it over to Ron, he's been pretty good at finding hyd motors and parts for me. You'll for sure have more grading power when you fix that governor. I've never ordered one from them before, but Minnpar does aerial parts, possible they may have a replacement Precision Governor, I just don't know myself. > http://www.minnpar.com/manliftparts.asp