Re: How to fix a Harbor freight 12 ton hydraulic jack


Matthew Spielberg
 

I had a Hoyer handicap lift. Designed for assisting the handicapped in and out of a bathtub. Perfect capacity for use as an engine hoist for little engines. Except for the fact that it leaked down.

I could not find a parts breakdown to locate the check valve, which I assumed needed cleaning and a new ball.

I found a hydraulic shop in Hayward, and left the ram. Yes, the repair would cost more than a new one. Three months later, he had not started on it. Four months later I picked it up. Five months later the shop folded.

BTW, I found a replacement Hoyer lift for free on Craigslist. Still have it. The repair to the check valve is simple, if you can locate it.

On 2/24/2021 10:01 AM, Dick Tuttle via groups.io wrote:
My favorite "fix" for the 12 ton press is to step up for the 12 ton air jack and rig up a foot pedal to operate it.  This allows both hands to be used for making setups, and the speed and pressure is totally controllable. (If you have an air supply, of course.)

Dick Tuttle


-----Original Message-----
From: Fred Cisin <cisin@...>
To: ArcaneAutos@groups.io
Sent: Tue, Feb 23, 2021 4:57 pm
Subject: Re: [ArcaneAutos] How to fix a Harbor freight 12 ton hydraulic jack

Can we assume that it is a conventional bottle jack used in it?

The most obvious possibilities is that it may be low on fluid, or it may
have air in it.  (which will let it pump up, but not under load, as the
air is compressible)

With the ram fully retracted, the fluid ("hydraulic jack oil", but some
try to get aaway with ATF), should come up almost to the hole.

http://www.chaski.org/homemachinist/viewtopic.php?t=101082
http://ecx.images-amazon.com/images/I/91aQFOul%2BAS.pdf

MOST can be adequately bled by pumping with the filler plug open, . . .


On Tue, 23 Feb 2021, sujit roy via groups.io wrote:

> Hi Have 12 ton HF press. The jack that came with it, has stopped working
> and I can't figure out how to fix it. There an many YouTube videos but
> not on this type. This type has a plug on the side. Underneath the plug
> is a screw. I removed the screw and put back which I think was a
> no-no.  Does anyone know how to get this type working again? The jack
> without load seems to go up, but when load is applied it, bounces up and
> down at the same spot. Sujit





-- 
Matthew M Spielberg
21855 Redwood Road
Castro Valley, CA 94546
(510) 886-5751
(209) 586-0250

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