Genie S-85 won't rotate

[Hunt44km]

I have a 2003 Genie S-85 boom lift. Serial # S8003-3563 I have owned it for about 10 yrs with minimal problems. Over time the basket rotate only works when it wants to and the jib the same thing. Then I started to have problems rotating the turn table with boom extended. Some times it will move but very slow!!! The unit runs and drives ok but the turn table only works with the main boom retracted. Added fluid because it has minor leaks. Checked connections, nothing obvious. After looking at it myself with little knowledge of how everything works I contacted the local dealer and they ran a few tests and said that the low pressure pump was bad and needed to be replaced. Because it was winter they wanted to haul it back to the shop to work on it. When they came to pick it up the axles didn't want to retract but after a lot of playing around got them in and loaded. When they went to off load it the steering wouldn't stay lined up and had a hard time unloading it. They worked on it for a couple of hrs on diagnostics and said the machine was junk and I should look at replacing it as the cost would be cheaper $40k. The fluid that was added to the hydraulic system was Dextron trans fluid as that appeared to be what was in the machine. They had contacted Genie and were told that the seals were now all bad and this was the cause of the problem. Because I paid less than 15k for the unit and didn't have 40k to replace I had it towed back and started working on it myself.
I have drained all the hydraulic fluid and replaced with new Rando HD MV. Replaced filters by pump low and high pressure and return filter. I had a bad battery connection at the post and fixed other grounding connections. I was able to extend the axles with no problem and the drive/steering seem to be working as they should. I bought a pressure test gauge and all the test ports read between 2500-3000 psi. I have disconnected the electric safety switch off the boom that shows that it is extended but it functions the same either way. I think my problem has to do with hydraulics but don't know where to start.
Any help is great!

 

[Txhayseed]

So to help rule out hydraulic verse electric lets break it down for some simple checks. Being that you had some electric issues lets start there. Its most common. What ever function is not working go the function manifold and find the coil/coils and start by testing to make sure the coils are in fact energizing when you activate the function. Then test to make sure the shuttle valve associated with that coil or coils is shuttling. I would start there first. Simple basic easy to check and it helps to take a bite sized approach to a problem like yours. As far as atf goes in the hydraulic system a few manufacturers run atf for the hydraulics and like most machinery they all source the same pumps/drives/valves etc etc. What genie uses jlg uses what jlg uses skyjack uses and so on. I would start electrical first then work my way toward hydraulics once i was convinced due diligence was done there first.

 

[skata]

In case it isn't obvious, you can get manuals for your machine at genies website.
Does the basket work the same when trying to operate it from the ground controls?

 

[Hunt44km]

With the boom retracted the coils are energizing when the switch is moved and the turn table rotates. With the boom exteneded the coils receive less volts but enough to make them function however it does not rotate. I know they have enough because the joystick allows the boom to rotate with about 3v of power to it when the boom is retracted. If I by pass both safety switches for electric that show that the boom is extended then it functions as it should but if either switch shows that the boom is extended then the coils still get electric voltage but nothing turns the turn table. What restricts the hydraulic flow when the boom extends? or am I missing something?

 

[Hunt44km]

In case it isn't obvious, you can get manuals for your machine at genies website.
Does the basket work the same when trying to operate it from the ground controls?

It does function mainly the same from the ground controls with the exception that the switches allow the hydraulics to operate at one speed. If the boom is extended the table won't rotate.

 

[Txhayseed]

One limit switch tells the machine the boom elevation and kicks you into low drive speed for elevated drive/function speed The other tells the machine that your boom has extended past the threshold and it will also push into low drive speed/function speed. Plus you also have the over center limit switch under the machine that rides the turntable. Both limit switches have to be in the stowed position to go into high speed travel. Once either or both limit switches hit the threshold you will see a slight decrease in function speed. Open up.the control box and get your schematic out. You need to verify with the limit switches are signaling that the signal is passing to where it should through the terminal block. Check your wires at the terminal block. Sometimes they come loose or are not making good contact. All testing is going to be done in the ground control box. If you jump the limit switches and it works then you already narrowed it down to most likely a limit switch is not doing its thing. Your going to need a schematic and your meter. You can also go in and tune your elevated function speeds and turn it up a few clicks and see if that helps. The programming instructions are in the service manual. But if it was me i would slues out those limit switches real quick and make sure your not going in circles.

 

[Hunt44km]

It does function mainly the same from the ground controls with the exception that the switches allow the hydraulics to operate at one speed. If the boom is extended the table won't rotate.

Correct. Boom extended then neither basket or ground controls allow to rotate. Some times it will sort of try but only a little bit.

 

[Txhayseed]

At this point with what your describing. Its pretty apparent you got an electrical issue. After 20 years working on aerial equipment i still couldn't tell you what your exact problem is based on on reading your posts with out standing in front of your machine. Anyone here can only help point you in the most logical approach to finding a solution to your issue. Your going to need to get the schematic and your multi meter and start testing.