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JLG 450 AJ boom lift

bowser ยท 2015-09-29 13:52

I have a hydraulic question. The platform that you stand in rotates left or right using a Helac rotator. It is very weak and requires a push sometimes just to get it to rotate either way. There are two hydraulic lines attached to the rotator. I detached one line, let it bleed into a bucket, open the control valve to put pressure to the other line, making it rotate in that direction right to the end of rotation. I held the switch to keep the system pressure on the rotator. The fluid kept going into the bucket after the rotator was at it end of travel. Do you think that's because the seals are leaking in the rotator or is there possibly a bypass when you get to the end of rotation? It's a lot of work to take the rotator out and I just don't want to do that for nothing. Please give me your thoughts.

Replies10
  1. #1lantraxco2015-09-29 14:10

    Seals.

  2. #2bowser2015-09-30 05:26

    Thanks Lantraxco, I just needed to know for sure. Now I have to either get it rebuilt or replace it.

  3. #3lantraxco2015-09-30 11:40

    Shouldn't be hard to rebuild, I think it's basically just a hydraulic cylinder inside there, with a helical spline drive.

  4. #4jatspic052015-09-30 18:02

    The Helac rotator has timing marks and they are difficult to see. You may want to look into the JLG rebuild program for the rotator, the price is reduced from the new one and you get a one year warranty. Hope that helps.

  5. #5bowser2015-10-03 07:02

    Thank you jatspic05, I have already looked into that. They don't have my particular rotator. Not available is the answer I get. Only a new one is available. I have time so I'm still weighing options.

  6. #6jatspic052015-10-03 09:49

    The only thing that has helped me is to heat the seals in hydraulic oil, makes it easier to slip them on the rotator shaft and end cap. My vision sucks so seeing the timing marks is a pain, you may have better vision so it may be real easy. As lantraxco said it isn't that hard to do. The two issues I see a lot is the 8 mounting bolts break off in the rotator and the top of the housing gets pitted so the seals don't seal. You'll know right away if one of those problems occur!

  7. #7bowser2015-10-04 05:54

    Thanks again jatspic05, I'm sure it's not the 8 mounting bolts or the top housing not sealing. It is definitely blow buy of the internal seals. I'm on the right track now thanks to you guys. I will take care of it over the winter. First I want to change the hydraulic oil and filters. It's due anyway. Maybe that is part of the problem. That is my next move. I bought the lift used and really don't know what anybody might have dumped in the hydraulic tank. I will feel better knowing the right oil is in there.

  8. #8jatspic052015-10-04 08:50

    Bowser, I didn't mean the bolts were not sealing, i meant that when disassembling the rotator from the basket the bolts break off. I'm sure you'll figure it out though.

  9. #9bowser2015-10-15 06:45

    Well, thank you lantraxco and jatspic05. We put a seal kit in the rotator and cleaned, greased up the bearing and all is well. Your guidance is appreciated many much!

  10. #10lantraxco2015-10-15 11:48

    Well done! :drinkup