Hydraulic Floor Jack not working... bleeding air?

[Quattro Pete]

I've got a 2-ton MVP jack like the one pictured here:

It worked fine for 2 years, but after my last move, it stopped lifting. I thought maybe I need to bleed the air out of it, which I did using some instructions I found here . If this is not correct (I lost the manual for this jack), please let me know what is.

I also checked the oil level - everything seems to be fine. When I don't put much load on it, it will lift, but when I put it under the car, it won't. What else can I check? A busted seal somewhere? Didn't see any...

Thanks!

 

[Mike_dup1]

A seal may be damaged and it won't hold the pressure any more. I had one go bad suddenly and it was a seal. Its was a cheapo and it trashed and got a Sears Craftsmen that was on sale.

You have tightened the release valve?

 

[got boost?]

that's a throw away jack, two years is pretty good. from your description, I'd guess a seal is bad.

 

[Shannow]

Another excellent reminder not to work on anything supported by hydraulic jacks.

An O-ring goes while you're under it, and it's game over.

 

[Ken4]

I have a almost 20 year old el-cheapo 2 ton jack and it still works! As you described, it also failed to lift once. Oil leaked out I suppose. What I did was to extend the piston out fully, open the top-up screw, pump it full of 20w50 until it overflowed, close screw. After that, it works great again.

 

[acranox]

I bought one like that for $20 from Autozone about 4 years ago. I use it a few times a year to change my oil, and the occasional under the car repair.
If it ever stops lifting, I'll take it apart, and find out how it really works...then I'll throw it out, and buy a new one.
Good luck with yours! It's such a simple device, it's probably nearly impossible to fix.