BlackHawk SJ-2 Vintage --- Leaking Down

[Bostopa]

Hi all got my old trusty 40 year jack that my uncle gave me when he was in the business and i was just a young boy.

So it was leaking from the front o-ring. Took it apart changed the o-ring to a 222 size, but still leaking a little and and with no weight on jack in full up position goes down in about 10 min.

When you look at the front nut and o-ring you can see a couple bubbles then a little oil start coming out...i mean not gushing just a tiny bit.

Now I'm thinking the internal seals need to be replaced cause the seals are letting the fluid bypass the cup at the bottom of the piston and oil finding its way up through the o-ring. Take a look at the attached pics.

 

[CraigStu]

I know you have some emotion invested in this jack but, if you replaced it w/ one of these,

https://www.harborfreight.com/25-ton-low-profile-aluminum-racing-floor-jack-with-rapid-pump-64543.html

or

https://www.harborfreight.com/3-ton-low-profile-aluminum-racing-floor-jack-with-rapid-pump-64544.html

you would soon realize that it is a massive upgrade in ease of use.

 

[road_king]

Purchase a seal kit here and replace the seals and o rings. I did this for my Milwaukee Model 20 a few years ago to fix a similar leak.

 

[Bostopa]

I know you have some emotion invested in this jack but, if you replaced it w/ one of these,

https://www.harborfreight.com/25-ton-low-profile-aluminum-racing-floor-jack-with-rapid-pump-64543.html

or

https://www.harborfreight.com/3-ton-low-profile-aluminum-racing-floor-jack-with-rapid-pump-64544.html

you would soon realize that it is a massive upgrade in ease of use.

Yeah your right last year during black friday I bought a new jack...guess this one still reminds me of my uncle...and has served me well from a young boy.

 

[Bostopa]

Guess I was trying to also undertsand could the leak from the front of the o-ring be coming from an internal seal?

 

[CraigStu]

I haven't had any jacks apart but have rebuilt many automotive master cylinders. From that experience I'd say yes. The outermost seal is more to keep dust out of the bore than anything else. If the internal seal, that should create the pressure, is leaking, then the area behind it gets filled w/ fluid. Eventually some seeps through that outer seal.

 

[paulsomlo]

Call Hydraulic Parts Supply in Sawyer KS, (620) 594-2247. You need the cup for the main ram and the correct o-ring that goes inside the nut. Do you have a large pipe wrench to remove the nut?

I've seen a friend's 1.5 ton Harbor Freight racing jack - it looks like a toy compared to an SJ-2, same rating.

 

[Bostopa]

Call Hydraulic Parts Supply in Sawyer KS, (620) 594-2247. You need the cup for the main ram and the correct o-ring that goes inside the nut. Do you have a large pipe wrench to remove the nut?

I've seen a friend's 1.5 ton Harbor Freight racing jack - it looks like a toy compared to an SJ-2, same rating.

I had it apart just to change the o-ring out with a 222 but then when I got it back together figured there was more internal problem with the seal and oil leaking by hence getting through the o-ring. Like I said above it's an old jack my uncle gave it to me from his shop when I was like 18 or 19...rebuild once and served me well for god almost 35 years now.

What can I say it's one of those things...and your right even though I did buy a Harbor Freight one...they just dont make them like they used to. This thing is a beast for only a 1.5 ton rating

 

[Stuart in MN]

Board member Hiball posted several tutorials a few years back on repairing hydraulic jacks, I think one of them was for Blackhawks. I'd use the search function in the upper right hand corner of the screen to see if you could find it.