Long Frame Floor Jack Identification Request

[rotavap]

Good afternoon,

I have a couple large floor jacks (below) that appear to have the same construction as each other except their cylinders. The only identifying information I can make out on the model ID tag is Made in Japan on the green unit.
Green unit: cylinder has 8A stamped into it
Red unit: cylinder has G12 stamped into it

I found a past thread with a similar looking model to the green jack that @Hiball I believe identified as a Weaver long frame (foot pedal, single hydraulic transfer valve, and single pump piston). Would really appreciate input from @Hiball or anyone with knowledge of these jacks regarding models, vintage, load capacity, and whether these cylinders can be rebuilt.

They currently will lift with many quick lift pedal pumps but begin lowering slowly immediately when I stop pumping. They lower smooth and quicker once I activate the release lever.

I appreciate any help,
Thank you

 

[mikedodge]

I have one that looks like that that's an old Strong Arm I think 5Ton. Which they still sell. It's one of those jacks that's under a couple different manufactures names. I saw a Norco one the other day.

 

[rotavap]

I have one that looks like that that's an old Strong Arm I think 5Ton. Which they still sell. It's one of those jacks that's under a couple different manufactures names. I saw a Norco one the other day.

Thank you! I wonder if these are both the same rating but I had not come across these two brands in my image searches. I appreciate your response.

 

[mikedodge]

No problem.
Different ratings had different physical sizes. I couldn't get to mine to see what pump is in it. I'm.guessung they're all the same and the numbers are something else.

 

[rotavap]

Update on searching in light of information from @mikedodge

On further inspection of the green service jack label found that it is a Sears Roebuck and Co jack which is Made in Japan, being a rebranded 3 ton Norco Industries jack (71000/YM-1000 (10 ton); 71030/YM-300m (3 ton)). I found Norco had a 2006 US patent issued (US7055801B2) for a quick rise hydraulic lifting jack which discloses technical drawings of this model with hand lever instead of foot lever and very slight modification of the cylinder design. That patent expired in 2024. I have found very similar models (frame and release mechanism) sold by Ranger (RFJ-10TL), American Forge and Foundry (3120/3130) and Strongarm (955/957) in the 5-10 ton range.

All their technical drawings can be found on www.hcrcnow.com. I found one of the jacks is missing a check ball spacer (clearly someone has been in the jack) that is obsolete but maybe a machine shop could make a new copy of the one I still have.

 

[mikedodge]

The jacks predate the patent by a long shot but not surprising they would come up with a revised version on pump from an earlier design.

For as lame as it sounds saying it that's very cool to see those other brands with the same jack and when you search that Ranger number there is also a BendPack branded one and more. It must depend on market because all the ones I've seen around here have always been Strong arm.

I was looking at that website a while back they have the catalog that looks like it's the actual Japanese manufacturer Yasui and has this interesting bit along with a lot of other similar looking imported jacks and other equipment.

https://media.hcrcnow.com/uploads/drawings/yasuicatalog.pdf