floor jack slowly retracts

[wazzabie]

I have a sears floor jack from the 1990s. It still is strong lifting up the truck. However it slowly retracts over night if lift upright. I'm not sure if it always did this. Should this be the expected behavior? I always put jack stands under the vehicle after lifting.

 

[dremu]

As you point out, stands are an absolute requirement and you can't rely on hydraulics to hold up the truck, especially while you're underneath.

To your question, I'd say the jack has a slow leak. It sounds, however, like it's really slow, not the point where you wanna tear it down and replace O-rings and such just yet.

-- A

 

[Kain]

better safe than sorry buy a new jack

 

[diesel4me]

Jack is showing its age--if its not losing any oil externally,it could be the seals on the piston are letting pressure leak by slowly...or maybe the needle valve you open to release the pressure has a groove cut in it from age,and lets pressure bleed by it..

I've had a few floor jacks that started refusing to hold a load for long,they "creep" down,on one I had,I took off the little pump piston to look at the seal,it has some oil oozing out of it,I replaced the seal with a new o-ring and found a steel ball bearing with a spring over it under the pump piston,the ball was all pitted and rusty and the spring was rusty..

I cleaned them up on a wire wheel and put it back together ,and it no longer leaked down...but I never fully trusted it,so I'd put a jack stand under the truck right away--as you should with any jack,new or not,never trust your life to a rubber seal in some import floor jack..bumper jacks are never to be trusted especially...sissors jacks like to flop over easy too...

 

[wazzabie]

The jack is not loosing any oil. The jack has served well all theses years. I'll check the condition of the pump seal and ball bearing. thx

Jack is showing its age--if its not losing any oil externally,it could be the seals on the piston are letting pressure leak by slowly...or maybe the needle valve you open to release the pressure has a groove cut in it from age,and lets pressure bleed by it..

I've had a few floor jacks that started refusing to hold a load for long,they "creep" down,on one I had,I took off the little pump piston to look at the seal,it has some oil oozing out of it,I replaced the seal with a new o-ring and found a steel ball bearing with a spring over it under the pump piston,the ball was all pitted and rusty and the spring was rusty..

I cleaned them up on a wire wheel and put it back together ,and it no longer leaked down...but I never fully trusted it,so I'd put a jack stand under the truck right away--as you should with any jack,new or not,never trust your life to a rubber seal in some import floor jack..bumper jacks are never to be trusted especially...sissors jacks like to flop over easy too...

 

[BADB0Y]

As everyone else said, use some jackstands anyway, and its not an issue really. I have an old Crapsman one that does this, and I just have to top off the fluid every 2-3 months and it's fine.