How to Fill a Hydraulic Bottle Jack Easily

How to Fill a Hydraulic Bottle Jack Easily

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Don’t know how to fill a hydraulic bottle jack? You might be surprised that it does not even take 10 minutes to do so. More importantly, you have to understand the importance behind refilling the oil in a bottle jack. All that and more will be discussed in this article.

At the same time, we are also going to talk about how a hydraulic bottle jack works so that you will have a deeper understanding of how to properly maintain your bottle jack. If you know the science behind its operation, it will now be easier for you to troubleshoot if there are any problems.

How a Hydraulic Bottle Jack Works

Before we discuss the specific process of refilling the oil in your hydraulic bottle jack, you should first know what happens inside it. In this way, you can see the importance of the liquid or the oil that you are going to put in it.

By now, you know that a hydraulic bottle jack is designed to lift heavier weights. This can be used for vehicles like trailers, pick-ups, and trucks. You really cannot use it on sedans and other smaller cars, though. That’s because its default height can be too high for those.

In the event that you can fit it on a sedan or another small car, the jack will just end up putting too much pressure on your car. Therefore, in no way should you use a bottle jack for vehicles that are on the lighter side.

So, how does a hydraulic bottle jack works? Unlike other jacks, it makes use of a liquid to lift weights. The science behind this was discovered by a French scientist named Blaise Pascal. He discovered that even though liquids, which cannot really lift anything, can prove to be strong in lifting weights when it is contained.

Applying that logic to a bottle jack, this is what happens:

  1. There is a reservoir of liquid inside the jack, which is the oil. Once you pull the handle, oil from the reservoir transfers to a piston. When the handle is pushed, the piston will force the oil to a larger piston.
  2. If you keep on pulling and pushing the handle, there will be more oil that goes into the larger piston, and this will increase the pressure of the cylinder.
  3. The result is equal pressure, which the jack utilizes as the power to lift heavy weights. The piston is forced to go up as there is too much pressure from the oil below.
  4. In terms of lowering the jack, you use the release valve as that will slowly put back the oil to the reservoir.
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Why Is Oil Important?

As you have read above, the oil is the driving force of your hydraulic bottle jack. Without it, there will not be enough pressure that is put against the piston.

The problem with this mechanism is that, as with all liquids, there will always be leakage. No matter how secure the reservoir or the locking points are, there will still be leaking. You might notice that some of the oil will leak when you are in the process of descending the lift of the jack. Therefore, the more you use it, the more that the oil will eventually run out.

This is why it is important to fill it with oil. When your bottle jack does not have enough oil in it, the chances are the force is lessened, which will result in slipping while you are lifting your vehicle.

The last thing that you need is to see your vehicle drop to the ground while in the middle of the lifting process, right? With that said, let us now go through the simple process of filling your hydraulic bottle jack.

How to Fill a Hydraulic Bottle Jack

Here are the things that you need:

  • Flat-tip screwdriver or other similar tools
  • Hydraulic jack oil
  • Newspapers or cloth
  • Rag
  • Plastic squeeze bottle

Note: It is important that you use hydraulic jack oil. Using other oils will simply damage the bottle jack.

Here are the steps:

Step 1

Put the jack in an upright position and make sure that you are on a flat surface. You can put rags or newspaper underneath to catch the oil that will seep through.

Step 2

Look for the rubber oil filler plug. This is usually on the side of the cylinder, which is near the top of the jack.

Then, pry that plug open with the use of a flat-tip screwdriver. Make sure to open it slowly so that the excess oil will not gush out.

Step 3

Take your hydraulic jack oil and put some inside the plastic squeeze bottle. Make sure that the plastic squeeze bottle has a pointed and long tip.

Place the tip inside the oil filler hole and squeeze the oil out. Keep on doing this until you fill the reservoir. Make sure that you do not overfill it. A good rule of thumb is to stop filling when it reaches at least 1/8 in. or 0.3 cm. under the filler hole.

Step 4

Once it is filled, push the oil filler plug back in the hole and make sure that it stays in place. You can try prying it open with your fingers just to make sure that it is closed securely.

Step 7

Using a cloth or rag, wipe the excess oil that might have spilled during the filling process. You have to do this after every session because oil accumulation on the exterior of the jack may also cause slipping as it affects its joints.

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You now know how to fill a hydraulic bottle jack. It is just a matter of using the right tools and learning the correct filling process. Remember not to overfill and always secure the oil filler plug. If you do not, then when you store away your bottle jack, the oil will just keep on leaking, and you will not be able to use it immediately once you take it out.

Furthermore, cleaning up after refilling is important because you do not want the oil to accumulate on your jack, which will lead you to more maintenance issues.

Last but not least, and this is probably the most important one, never operate a bottle jack that does not have oil in it. You might be tempted to do so, but trust us, do not do it.

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