Just to clarify to others what I was asking Hiball. The “base o rings“ are not the same seal as the o ring/plastic retainer seal found on the main ram on other jack brands that has longevity problems. The Omega 27036 jack does use a U cup on the main piston ram. These o rings are in a different place... a location that adds an extra annoying step to do a rebuild.
By the way, same jack here at half the price... (you should also price compare to your local hydraulic shop.)
https://www.tooldiscounter.com/prod...Iyebuqti58QIVtyCtBh1oQQnBEAQYASABEgIpZfD_BwEw
I wouldn’t say the single pump quick lift jacks have any longevity issues pertaining to the design. Again, I’m only talking about the quick lift function. I’ve talked to multiple customers who have gotten good service from the Sam’s club Michelin jacks/Napa etc. where things started going downhill is when they started cheaping out on the seals with the design.
Clarity on how the Single pump piston jacks utilize quick lift, speedy lift or Magic lift depending on marketing versus the twin pump versions for anyone not familiar.
Single pump, The Jack carries a tube that runs perpendicular to the cylinder and inside the Main Ram. When it’s not under load, the valve sends oil towards the tube and due to its small diameter it increases the stroke, thus gives you a fast lift. At the same time the Vaccum created by the main ram extending pulls oil into main cylinder. Once the lift arm reaches a load the pressure increases to lift the speed side valve and force oil into the main cylinder (Power). The problem is, On some of the cheaper models, either the quick lift tube Seals fail or the Main ram seal doesn’t pull enough vacuum to keep up with the stroke, and then things get crappy quick.
The twin pump units work both sides at the same time, the speed side piston is larger to push more oil, thus transfers more oil = More stroke. Once load is reached, Pressure increases and lifts the speed side valve and bypasses to allow only the power side to work alone. Like most equipment, reliability comes from less working parts. The single pump jacks can be made reliable as I stated earlier, but it takes a manufacturer to request solid components during the build. I think with most manufacturers going to the twin pump setup and utilizing Ucups all around it’s a better system.
Hope this Helps.
@ajchien Only referring to the single versus dual pump setup, the only thing that can be added in regards to Ucups versus Oring retainer on the Main ram piston seals is that Ucups create more wall pressure and pull more consistent vacuum versus the Oring retainers on the single pump models. This becomes very important when oil conditions are poor due to contaminates etc.
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