1996 JLG 45HA repair questions

[DirtyHoe]

If you flip the wheel motor speed switch it powers up a solenoid valve that sends a signal to all four drive motors to change the position of the swash plate inside the motors changing the displacement as they're variable displacement motors, which again will change the speed of the drive motors.

I don't think there is any electrical wires down to the individual motors, so this "signal" is fluid to the four motors?
Since my PQ controls seem to be original and quirky I'm going to buy a new one to see how it behaves compared to my old ones. Maybe this will help troubleshoot?
I'm just amazed at how much technology is crammed into this machine compared to my backhoe and skid steer. It's a much bigger challenge to repair.

 

[DirtyHoe]

While I've got the machine blocked up in the air to fix a flat and paint the rims is there any testing I can do? Should any hydraulic pressures be taken for diagnosis?

Steve

 

[willie59]

Been too many years since I've worked on those machines, I don't recall the test procedures for those machines.

 

[DirtyHoe]

Looking in the parts manual the basket control came configured with a PQ controller for driving and the steering was a toggle switch(my configuration). They also show a PQ controller that is a combination of steering and drive function. Is this something I can upgrade to since I need a new controller? Or is it a lot more involved than simply plugging the toggle switch wires into the controller? Not sure how the dual purpose control works, but seems like it would be a lot easier to drive and steer with one control instead of using both hands on different switches.

Steve

 

[willie59]

Yes, it should have a PQ controller with the steer control on top of the controller joystick lever. Get your parts number from the parts manual and contact Hindley Electronics in Bowling Green Ohio and get a quote for a replacement controller from them.

 

[DirtyHoe]

Mine has separate steering toggle(lower left)and separate drive PQ controller(lower right). I would like to upgrade to the PQ controller you are referring to. Just wondering if the wiring is as simple as hooking up the toggle wires to the new PQ controller or not.

 

[willie59]

Ahh, that's the old school PQ controllers, been years since I've worked on those. I'm not totally certain, but I don't think that type of PQ came with the steer switch on the lever, later models did, but their circuit card is different than the ones on that model. I don't know if the later model controllers would work on that machine. I'd say just stick with the steer switch on the left.

 

[OFF]

I'm sure that new PQ controller body I'm sending you will work. It's got the steering rocker switch on the knob. The wiring from the steering rocker switch is totally separate from the wiring for the rest to the controller. Only Three wires, power in, right & left output. It's got to work.

 

[DirtyHoe]

Here is my latest struggle. How do I get the worm gear off? Is it a tapered press fit onto the shaft? Key or no key? It looks like the three tapped holes are for a special puller? The top piece was hard to get off with a torch and pry bars. The key and bore were rusted solid to the shaft. The smaller worm gear(#107) that is driven by the motor ate into the aluminum housing. So the platform rotation has a ton of slop in it.

• What is the bracket(#13) for. Mine is gone.
• What are the 4 roll pins(#108) for?

Thank you in advance,
Steve

 

[DirtyHoe]

Also, any idea how the pin at the end of the boom comes out? It has a hex on one end and the other takes a through bolt(missing) Someone welded a bolt to the outside of the frame and the end of the pin rather than do a proper repair. I ground that mess off and I need to rotate the pin to align the holes. Is it threaded? It would be nice if the service manual had some basic instructions on how stuff goes together.

 

[OFF]

You want to start with the basket? Your #13 bracket is a like little reaction arm and it needs to be there. That's the part that always used to shear off whenever someone ran the edge of the basket into a non-movable object. Is you basket really floppy? Turns which ever way the wind blows?

Also, you see #7 in your diagram? Those are cupped washers, and as they are compressed, they apply force to the clutch disc and tension to the basket rotate. Take that big bolt out, see if the washers are still there and stacked properly. See link, they act like a spring.
https://en.wikipedia.org/wiki/Belleville_washer

Your pin is held in by the lock bolt. That hex on the other side only provides a way to rotate the pin so that the lock bolt can lined up. The way it sits now, you should be able to drive it out. You might want to try rotating the pin before you try knocking it out, just to see how hard it's going to be.

 

[DirtyHoe]

OFF,
Sorry for the confusion, but I posted the wrong parts diagram. The bracket goes to the low mount style platform. I have the standard platform so I don't need the bracket.

The thrust bearings, shims, cupped washers, and regular washers all disintegrated. The small worm now slides back and forth about .5 inch. It is sliding in and out of the hydraulic motor coupler. Is the large worm wheel installed on a taper? It won't budge with plenty of heat and prybars. I think I will machine a steel puller plate with drilled holes to pull on the 3 tapped holes of the worm wheel.

Steve

 

[DirtyHoe]

I can't get the worm wheel to budge using penetrant, rosebud, and a custom made puller. If I use much more heat I will melt the aluminum housing. I don't want to cut and ruin any parts yet because the shaft($340) and gear($420) is a lot of money.

When this assembly is working properly does the worm wheel spin freely on the shaft besides the friction brake tension?

 

[DirtyHoe]

Has anyone ever serviced one of these torque hubs? I have a leaking rear seal, and a little metal debris in the gear oil. So far everything looks great on disassembly. I removed the stubborn flat snap ring(retains outer bearing) and then the spacer. Looking at the service manual and parts manual the hub should slip right off. As you can see in my picture it won't budge at all, but I don't want to reef on it until I get some feedback on why it may be so stuck. Shouldn't the inner race be a light press fit at most?

Thanks in advance for the help,
Steve

 

[OFF]

Other than the bearing races being a very snug fit on the spindle, I don't see, or know of a reason it shouldn't pull off there. You should be battling that outer bearing only. The inner bearing should just pop the seal and stay on the spindle. Nice puller setup, have you put some force on it yet?

 

[DirtyHoe]

OFF,
I put a fair amount of force on it and was expecting it to move. I'll try it again with more force.
I was panicking that I didn't have a big enough puller until I figured out I could sneak behind the gear to hold on the back side.

Crazy story: I was driving late at night on a county road. Saw an object in the middle of the road and it was too late to dodge it. So I ran over it with my Camry and it was an awful sound. I pulled over and went to check it out and it was the big puller I'm using in the picture! Both the car and the puller survived. I'm guessing it fell out of a service truck.

Steve

 

[TheFixer]

Ahh, that's the old school PQ controllers, been years since I've worked on those. I'm not totally certain, but I don't think that type of PQ came with the steer switch on the lever, later models did, but their circuit card is different than the ones on that model. I don't know if the later model controllers would work on that machine. I'd say just stick with the steer switch on the left.

I used this controller to replace my drive controller. No issues so far, works better now.

https://www.ebay.com/itm/JLG-Joysti...e=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649

 

[TheFixer]

I don't see why your gear or hub should not come off. You can try to put the hyd motor back on the basket and see if that will break the gear loose. The gear should spin on the shaft, and the clutch pressure moves the basket. Unless this went bad at sometime and somebody did a repair so the gear is fixed to the shaft. I adjusted mine, but never had to take it apart.

 

[DirtyHoe]

Fixer,
Thanks for the response!
Lots of corrosive Oregon rain I'm afraid. Because the gear was not able to slip, every time the basket ran into something it wore the small worm into the aluminum housing by about .375". So I need to get it apart and make some spacers.

The hub oil was decent and no water damage. I've never seen that much press fit on a tapered roller bearing to a spindle. It has a very stiff split ring to keep it all together anyway.
My overall opinion is JLG just make everything too tight of a press-fit for all pins, bushings, etc. The rain welded it all together over time.

Steve

 

[TheFixer]

That is one rusty machine. I wish mine was 4x4, but I've managed to get by without it. When I set my drive pressure, I think I set it a bit on the high side of 3k, just to make sure. They don't have a lot of power in the high speed mode, but when it gets moving it seems like you are doing 60mph lol!!