Hydralic sissor car hoist question Any hydralic guys here?

[drifter]

I have a 1200# rive on hydralic sissor hoist.I bought it used and it has always had a problem when letting the car down.The prblem is when it gets about 1 1/2 feet from the ground it stops and it won't lower any farther.The safetly lock system is a pedal and a bar goes across to the other side to the lock well the guy i got it from took the bar the connects the two locks together off.So this is how he showed me to let it down.When to stops you put it up a bit and only lock the one side and let it down so it tilts then put it up fast release the locks and try and let it down again some times you have to do this a few times.When it does not come down all the way its not stoping from a lock problem its hydralic somthing is making the one side stop any ideas?

[Masher Manufacturing]

I need more info.

Does this have one scissors and cylinder or two scissors and cylinders?

Regardless of the system, many units have a velocity valve to prevent collapse in the event of a burst hose. This works by monitoring flow rate out of the cylinder, if the rate exceeds X GPM the valve closes. The valve resets when flow is going into the cylinder.

A scissors lift does not have a constant flow rate during operation. Flow when lowering starts out low then rises as the lift nears the ground. This can cause the velocity valve to close.

Some systems have a adjustable flow control, ( not to be confused with a pressure relief ) turning this down might help the situation.

A two cylinder system needs either a mechanical link or a flow balance valve to keep the lift level. The flow valve can jam due to dirt and cause the lift to stick.

[drifter]

Masher my lift has two cylinders so what do you think i should try first to fix it? Its just for personal use so its not like its used ever day.But it sure seems like its the one side that locks up from going down about 1 1/2 feet before to the ground

[Masher Manufacturing]

I'd follow the cyl hoses to the flow balance valve then take it apart for cleaning. You'r pretty much on your own for the details on how to take it apart.