How to Fix Floor Jack that Leaks Down
Most of the information you’ll find on this subject begins with this advice: Find the source of the leak.” While this may seem far too obvious, there are a few places you should look immediately, because of the design of most floor jacks.
In fact, if you look at these four places, you’ll usually find the leak quickly. If you don’t locate the problem right away, you will need to focus on the pressure-release valve in almost every situation. Look for visible evidence at:
- Ram/piston rod
- Compression ram
- Pressure-release valve
- Fill cap/reservoir
With this very general advice in mind, you can start to look at the problem in more detail. You may notice that the lifting arm/handle settles slowly after it’s raised, which it certainly should not do. Start the inspection process by making sure your reservoir has the right amount of hydraulic fluid in it.
You can try purging air from the system by lifting the arm and allowing it to drop slowly, which should push air out. If full fluid and purging air don’t correct the issue, you’ll have to address the leakage with repair/rebuild.
It’s possible you can increase pressure control by turning the valve, though it’s best to consult your owner’s manual for guidance. If it’s time to make repairs, this adjustment probably won’t fix the problem. Start the repair process by releasing all pressure. The next step will be to drain all the old hydraulic fluid out.
This may involve turning the jack on its side or even upside down and letting the fluid drain into a catch-pan. You may find some specific details on the model you have that are slightly different, so be sure you gather all the information available on your product.If you’re ready to remove the part of the jack that’s leaking, you’ll probably be able to use some basic tools, such as an adjustable wrench, needle-nose pliers, and perhaps one or two more. For some of the older jacks that you want to continue using, you may need a ratchet set to get to a leak around the fill reservoir. Once you get access, your first step will be to remove the old O-ring and replace it. This can be one of the first places to look for visible leaks.You should also be aware of any springs beneath the pressure cylinder. These are crucial to proper operation, so make sure you set them aside and replace them correctly. With many floor jacks, you should be able to separate them into several pieces, perhaps by removing the two main side pieces to expose the inner cylinder. You will also open the cylinder to inspect the seals, which is a location that could very well be causing the problem.
You’ll remove the ram/plunger and take the O-ring out with needle-nose pliers. Make sure you have the proper O-ring, one that matches the thickness and diameter of the original. Before placing the new ring back into position, you should coat it with a small amount of hydraulic fluid, using your fingers.You can probably find a rebuild kit for your jack, which should have the rings and other small parts you need. Plan on spending the equivalent of about $50 for a good kit and shipping, but that’s just a general guideline. You may be able to find the parts you need at a local auto-parts or equipment parts store.
Carefully place the ram back into the cylinder, paying attention to the O-ring, which you definitely don’t want to damage. Reassemble the housing and put the frame pieces back in place. In many cases, you have taken care of the leakage problem. If there is still a problem with the slow leak, you might want to inspect the cylinder and the seals closely. In some cases, a very small “burr” or bump in the metal of the cylinder can mark the seals and O-rings, allowing fluid to leak past in small amounts.You may be able to get the job done with rings purchased at the hardware store, but you may discover some fitting problems with generic O-rings. Parts kits designed to rebuild a floor jack will generally have what you need, sometimes even a few small parts that you may not need to replace. It’s still money well-invested.
You may also find that a thorough cleaning will help the performance of your floor jack. Dirt and debris in the fluid system can be a real problem. In fact, this can damage the inside of the cylinders, which may be the cause of the marks on the interior of the cylinder that damaged the rings and seals mentioned earlier. A careful, visual inspection is always recommended. A quality floor jack, well-maintained can serve you for a couple of decades.