Question - Hydraulic Floor Jack

jollyjoker

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Have a dumb question, my apologies if already addressed. I have two jacks that just don't lift anymore. They'll rise until they contact the frame, then won't raise any more. (Yes, they have plenty of fluid in them.) My understanding is that these things are essentially bottle jacks mounted sideways in the frame. I know you can buy sets of rubber O-rings online to rebuild them. What am I missing? Seems like a fairly straightforward device - why are they crapping-out on me? Anybody here ever "rebuild" one? Is it worth the effort, or should I just haul them over to the scrap yard, and stop by Harbor Freight on the way back? Thanks for any advice!
 
Either the pump is bad or the valve is bad. Floor jacks have a valve that holds the fluid in the jack cylinder in place so that the jack platform continues to lift, when the handle is turned the valve is opened and the fluid flows back into the reservoir to lower the platform. What usually happens is that a piece of debris, usually from a failing o-ring, gets stuck in the valve and it leaks. This allows the jack to raise until it meets resistance and then the fluid leaks back out as fast as it is pumped in. I would suggest taking the valve body assembly apart for inspection, it it is a bad o-ring, that is usually a simple fix. Just be sure to use o-rings that are high pressure rated.
Most of the time, if the pump itself has failed it will usually be because the bore is scored. If that is the case, the jack is probably junk. The Chi-Com jacks sold at Harbor Freight are famous for soft pump castings that wear quickly, they are not designed for continuous use. The Jet brand 2.5 ton jacks are a particularily bad POS.

Dave
 
jackstands are your friends....don't forget that that hydraulic jack is being held up by a questionable O ring...specially if its built in china
 
I had that problem and got an O ring kit. Took everything apart, cleaned and installed new O rings and fluid. Had to buy a massive socket for the job, but it was cheaper than a new jack.The jack has been fine for years since then.
 
Please stay away from HF or you will find yourself revisiting this question within a year. You get what you pay for.
 
please use jack stands x2 -

I had a piece of wood 2x4 on the jack plate, and it split in half while lifting, and the car dropped the thickness of the 2x4 instantly. it would have hit the ground if I dint have stands under there I had the front wheels off. woulda took out whatever was under there, like a leg or head etc.


try not to die -

- saylor
 
If the wheels stay on while I do whatever needs being done, I.E. I'm not doing brakes, wheel bearings, suspension, I lean more towards cribbing blocks rather than jack stands. Super easy to make and nothing holds a car up like it's own suspension.

Like zo;



And this is why..

 
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They'll rise until they contact the frame, then won't raise any more. (Yes, they have plenty of fluid in them.)
jackstands are your friends....don't forget that that hydraulic jack is being held up by a questionable O ring...specially if its built in china

I take your reading comprehension is that of a 2 year old, read it again Cancritter!

Please stay away from HF or you will find yourself revisiting this question within a year. You get what you pay for.
Sorry Matt, my brother had one for over 5 years and many lift ups on it with no problems, sold it when he moved.
As for weather or not the pump is bad and not a O-ring Jollyjoker, with some search effort, you'll find that you can buy a replacement pump for the old frame and swap it out if needed instaed of buying new. Good Luck
 
I’m still not going to Harbor Freight for a floor jack.
 
How about this dematt?:rolleyes:

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Harbor Freight Automotive lift # 91315
 
Thanks to all who replied. Think I'll try and tear them apart and at least check out the O-rings, when the weather gets a little warmer. Garage is so packed I can't even turn around in there now. And yes . . . I always use jack stands when I lift (I do appreciate your concern!).
 
I had a Sears jack my father bought me in the 70's. It quit working like you described around 2012. I didn't have the heart to chuck it, Sears was no help on parts. I bought a HF unit and it worked ok for a few years, till it sprung a leak! I HATE oil on my floors and that thing pissed oil everywhere. I took the casters and the handle and left it at the curb. Got on the internet, found a 30 dollar kit by searching the part number and within a few days of cleaning and my neighbors help I was back in business! Try that with that Chinese junk! Good luck, you can find some US made jacks if you look hard. Northern sells a unit for around 350 that was what I was going to buy if I could not get my Sears fixed.
 
I had a Sears jack my father bought me in the 70's. It quit working like you described around 2012. I didn't have the heart to chuck it, Sears was no help on parts. I bought a HF unit and it worked ok for a few years, till it sprung a leak! I HATE oil on my floors and that thing pissed oil everywhere. I took the casters and the handle and left it at the curb. Got on the internet, found a 30 dollar kit by searching the part number and within a few days of cleaning and my neighbors help I was back in business! Try that with that Chinese junk! Good luck, you can find some US made jacks if you look hard. Northern sells a unit for around 350 that was what I was going to buy if I could not get my Sears fixed.

Your are very correct, the Chi-Com jacks do not have a parts or service network. If it dies under warranty, they just give you another one at Harbor Freight. And it will do the same thing, but by then the warranty is gone.

Dave
 
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