Rotary lift not lowering

[blk00ss]

Ok so I finally got my lift wired up and what not. Having some very strange problems tho. First off when I first started it up after filling with fluid, it would raise fine but not come down at all. I figured it needed some weigh on it, so I got me and a buddy to press down on the legs. It finally started coming down. Very slowly tho. But as its lowering you can hear and watch the motor spinning. It's very strange. Like a whirring noise. All the lifts I've ever used when lowering the lift you couldn't hear anything except the cylinders.

And another thing it does is this. At first it would stay up on its on. Now when you raise it and left off the button it comes down on its own without using the release button. BUT I put one of my cars up in the air about three foot and it was holding on its own just fine. Not leaking down at all. Then I went to lower it and NOTHING. Wouldn't budge. The release lever wasn't doing anything. I finally got it to start coming back down by bumping the raising button a few times quickly. But as it was coming down it was making that very weird noise from the motor. And I also wasn't using the release button lol.

Oh and the times it was staying on its own it wasn't because it was on the locks. I had them pulled out of the way trying to get it to come down.

So has anyone seen anything like this before?

 

[PDM]

What kind of Rotary lift ?

I had issues with one of my Rotary 2 post lifts (in bay, 10,000 lb symmetrical) where the lift/lowering buttons are the soft press type, and if you hit them without really firm pressure - it would not lift the hoist evenly - and would cause the lift to not lock in evenly - therefore not allowing it to lower the vehicle.

Only solution was to take a heavy 2 x 6 and jack and lift the one side that was lower and then raise the lift until it could be lowered back into a locking position.

I was never a fan of the Inbay modules - they were "touchy" to use (had to really exert direct pressure on the contacts) and I had one go with under 60 minutes use on an asymetrical 2 post that cost over $1K to have diagnosed and replaced. (no warranty as the hoist was over 4 years old, yet I had barely used it in that time.

 

[blk00ss]

It's a SPOA9. It does have what you call the soft lock buttons. But it lifted very even. Just wouldn't lower right for some reason. It's almost like its back feeding and spinning the motor backwards when it starts lowering.

 

[c39er]

Sounds like the pump check valves are not working properly.

 

[blk00ss]

That's what I've been told. How hard are they to replace?

 

[blk00ss]

Bump

 

[blk00ss]

Just figure I would update this. I finally got around to pulling the power unit off. I looked it over and seemed easy enough to take apart. And that's exactly what I did. I found a check valve in the hydro pump. The plastic ball was stuck in the down position. So I free'd it up to where it now moves freely. And also cleaned everything out really good. Put it back together. Wired her back up. And now works almost flawlessly! Only problem I'm having is about 1/2 the way up it causes the lift to shudder. I'm thinkin it's a rough spot on the columns where the arm body and guides are riding. I got some sand paper and lithium grease I'm going to try fixing it with. But I was finally able to use it today for the first time. Sure is a lot easier than puttin the damn car on jack stands.

 

[skamp]

Just figure I would update this. I finally got around to pulling the power unit off. I looked it over and seemed easy enough to take apart. And that's exactly what I did. I found a check valve in the hydro pump. The plastic ball was stuck in the down position. So I free'd it up to where it now moves freely. And also cleaned everything out really good. Put it back together. Wired her back up. And now works almost flawlessly! Only problem I'm having is about 1/2 the way up it causes the lift to shudder. I'm thinkin it's a rough spot on the columns where the arm body and guides are riding. I got some sand paper and lithium grease I'm going to try fixing it with. But I was finally able to use it today for the first time. Sure is a lot easier than puttin the damn car on jack stands.

Cat sells some anti-chatter you can add in the fluid that may help. I did this on my MaxJax and it got rid of the chatter/shutter I had.

Steve

 

[blk00ss]

Yeah I'm going to get some of that as well. But it only does it in that one spot. Not the whole way up.

 

[c39er]

That CAT additive works. I had the same issue. The additive pricey-I think about $22.00.

 

[blk00ss]

I've got a buddy of mine who works for CAT. I'll ask him if he can scrounge me some up. How much do I need? The system holds around 5 gallons.

 

[c39er]

I used less that half that quart container for my lift.

 

[Altec]

I had the rotary lift in my bay bind up once, and after that it shuddered. I greased the living hell out of it, and put a lighter car on it for a half dozen cycles. Cleared up.

 

[blk00ss]

How did it bind up?