New guy floor jack questions

[jimmga]

Gentlemen,
I am looking for information on repairing an early Sears 1/12 ton floor jack made by Blackhawk. It appears to be a SJ-2 model. I have sent for a repair kit from Lazzar's repair parts. It is entirely surface rusted but the piston looks ok as it was compressed in the cylinder. Any suggestions on repairing this jack? Thanks!

 

[KZ1000J]

First, welcome to Garage journal.

Second, I have no clue but this link would be a good place to start.

http://www.garagejournal.com/forum/showthread.php?t=197787

KZ

 

[jimmga]

Gentlemen,
Excellent information! I have not figured out all the avenues of the site and there is a lot to learn. Thanks KZ

 

[tommyrs70]

I am in the process of rebuilding my Sears (Blackhawk) 727.12101 and happy to share the progress. I bought it new in 1974. The Sears jack is very similar to the Blackhawk SJ2 but not identical. The ram/plunger design is slightly different but otherwise seems to be the same.

Here is the owner's manual for anyone in need.

[/URL][/IMG]

[/URL][/IMG]

The Rebuild: I disassembled the jack, wire wheeled, sand blasted, primed and painted all the parts. I just received the rebuild kit from eBay and am trying to identify some of the smaller washers.

EBAY KIT:

The rebuild kit comes with a parts sheet but no installation directions. I am having a difficult time identifying the wiper ring #59 and the #60 packing on the valve #57. In the pic below, there are three similar sized pieces, #1 one is leather, flat on both sides, #2 is leather but tapered to fit in a seat, and #3 in layered rubber. I am not sure where they go. Little help here would be appreciated!

I am also having a difficult time removing the 7/32" ball from the Base #70 for the release valve. It is stuck in the bore. I tried whacking the body with a hard mallet but no luck. Is there any way to get air pressure into the bore?

Maybe Hiball will lend his expertise. Any suggestions are appreciated! Thanks!

 

[FANTM58]

Your wife is going to be pissed when she finds out you used her
Christmas hand towel for this project !️

 

[Boilerhouse]

I rebuilt a Michelin floor jack recently. The kit, which likely covers a range of floor jacks, contained several washers and O rings which were not for my model, and, unfortunately, also did not contain one O ring which was needed, so I purchased it separately from a local hydraulic shop.

 

[tommyrs70]

Your wife is going to be pissed when she finds out you used her
Christmas hand towel for this project !️

Yea, You should see what I used her Easter tablecloth for!

 

[Bcom]

Ive actually never seen anyone take the time to rebuild an old floor jack before. Hats off to you good sir. Usually its just easier to pick up a quick pump 3ton HF jack for $80 thats works very well. Good luck on your project. Funny quote about the Christmas hand towel though hehehe

 

[tommyrs70]

I was able to remove the small check ball with a little heat from propane torch but having a heck of a time removing the hydraulic cylinder from the base.

 

[tommyrs70]

Thanks for the support, Bcom! Love the challenge of fix'n stuff. I'm a science teacher and off for the summer so this is just one of my many projects. Working on a few classic cars and some building projects. Picked up some really awesome 240V Powermatic tools, a table saw, combination drum belt sander and jointer from a friend who is a retired woodworker. The drill press and planer all already in the garage.

 

[Roberts210]

Ive actually never seen anyone take the time to rebuild an old floor jack before. Hats off to you good sir. Usually its just easier to pick up a quick pump 3ton HF jack for $80 thats works very well. Good luck on your project. Funny quote about the Christmas hand towel though hehehe

Why would you want to trust a leg or your arm or your life with Asian metallurgy and off-shore jack engineering?

 

[tommyrs70]

Had a heck of a time installing the piston back into the cylinder. Soaked the cup and backing washer ( leather ) in hydraulic fluid to soften them up a bit. Since I was unable to unscrew the cylinder form the base, I had to finesse the piston into the cylinder from the top. Really don't think that is the correct /best way. I tried to remove the cylinder by heating up cylinder and the base with a torch to no avail. Still couldn't get it to unscrew. Needed either more heat or leverage or both...

Completed the pump re-assembly. Added fluid, bled and it seemed to be pumping ok without a load so I installed it back into the frame but it is not working. No lift whatsoever. So I either damaged the ram cup seal installing it or there is something not working with the check valves. Back to the drawing board.

 

[cubfarm 1]

Did you remember the ball under the release u-joint? If you lift the ram up by hand and it will not stay it should be either the release ball or the upper check ball not seating. If you damaged the ram cup it may recover it's shape with a bit of pressure but it should move with no load but may settle a bit. If you look at the end of that release stem with the packing nut it will have a bit of a "dimple" from wear from the ball. Jack does nothing without the ball in place.

 

[tommyrs70]

Thanks for your help, cubfarm! Yes, i replaced the check ball under the release u-joint with a new one from the kit. I noticed a simple at the bottom of the valve. Any other ideas? Tom