Warning

 

Close

Confirm Action

Are you sure you wish to do this?

Confirm Cancel
Member Login

Site Notices
1/22/2020 12:12:56 PM
Posted: 4/20/2016 9:35:35 PM EST
A friend at work said I should lower my lift to rest on one of the safety-stops, and not have the car resting on the hydraulics for more than a short period. Should I be doing this?

This is on a 6000lb scissor lift.

Thanks.
Link Posted: 4/20/2016 9:37:14 PM EST
Link Posted: 4/20/2016 9:42:56 PM EST
Fpni.

Most hydraulic systems will back feed at some point in time and release pressure. There are exceptions to this, but more on the rare aide then common. As hydraulic oil will expand and contract with heat. Thus the majority of systems are designed with some give.
Link Posted: 4/20/2016 9:44:18 PM EST
I think it's closely compared to using a floor jack and jack stands. I would rather trust metal on metal to support my vehicle for a longer duration, and rely as little on a pressurized liquid cylinder as I could. I feel like (meaning I have no supporting information for this) failure rates are lower with jack stands and safety stops.
Link Posted: 4/20/2016 9:48:48 PM EST
Originally Posted By VikingPanels:
A friend at work said I should lower my lift to rest on one of the safety-stops, and not have the car resting on the hydraulics for more than a short period. Should I be doing this?

This is on a 6000lb scissor lift.

Thanks.
View Quote


OSHA has been going around fining shops where they find cars on lifts that aren't lowered to the safety locks. Heard pep boys got hit bad like $10k per violation.
Link Posted: 4/20/2016 9:51:23 PM EST
[Last Edit: 4/20/2016 9:52:29 PM EST by Torque556]
It's good for the o-rings to relieve the pressure. It'll last longer.

Eta: Open the valve to relieve pressure then close it again. If the mechanical stop fails the fluid will still hold it.
Link Posted: 4/20/2016 9:51:29 PM EST
It'll hurt if a hose pops off and drops it.
Link Posted: 4/20/2016 10:05:04 PM EST
Hurt...no....increase wear and tear on the hoses and seals...yes.......I can't stand up straight if a car is on the top lock....I need that extra inch or 2 above the lock
Link Posted: 4/20/2016 10:09:08 PM EST
I have a lift that doesn't always catch the locks on both sides. It would suck if I left it on the hydraulics overnight and came in the next morning to the car sitting sideways on top of my toolbox.
Link Posted: 4/20/2016 10:11:21 PM EST
Discussion ForumsJump to Quoted PostQuote History
Originally Posted By evilar:
Hurt...no....increase wear and tear on the hoses and seals...yes.......I can't stand up straight if a car is on the top lock....I need that extra inch or 2 above the lock
View Quote
I have the same problem.
Link Posted: 4/20/2016 10:17:04 PM EST
Discussion ForumsJump to Quoted PostQuote History
Originally Posted By Foxtrot08:
Fpni.

Most hydraulic systems will back feed at some point in time and release pressure. There are exceptions to this, but more on the rare aide then common. As hydraulic oil will expand and contract with heat. Thus the majority of systems are designed with some give.
View Quote

That's right, there is leakage around the valve spool and other components that will release the pressure over time. The leakage is collected by the case drain and returned to the reservoir.
Link Posted: 4/20/2016 10:20:41 PM EST
Lifts on locks and all hydraulics in a zero energy state on machines..

If someone hits a lever or valve nothing should happen due to gravity or pressure.
Link Posted: 4/20/2016 10:30:15 PM EST
I can attest to the fact that you do not want to leave a car up overnight on a lift with a jack stand supporting the motor. I came in the next morning and everyone was gathered around the car just looking at it. The stand slipped off as it lowered and did some damage but I can no longer just what or how much. This was about 25 years ago.
Link Posted: 4/20/2016 10:37:36 PM EST
Originally Posted By VikingPanels:
A friend at work said I should lower my lift to rest on one of the safety-stops, and not have the car resting on the hydraulics for more than a short period. Should I be doing this?

This is on a 6000lb scissor lift.

Thanks.
View Quote


Yes you should do it.
Very much so.
Link Posted: 4/21/2016 5:33:55 PM EST
Thanks for the replies. I fell to sleep after posting the question. LOL.

The safety stops engage automatically as the lift is raised. I'd never get under a car with just hydraulics guaranteeing my safety.
Top Top