Last updated on August 20th, 2021

Do you own a grease gun? If it’s giving you a tough time at the time of loading, then this article is here for all the things you might want to know about these guns.

If you have any vehicle or machine that needs lubrication, then you may need to purchase that. To know how to use a grease gun and how to load and prime a grease gun. keep reading the article.

All about grease guns:

Do you want to know what are grease guns for? Tons of online researchers talk about the importance of this tool for lubricating machinery.

Grease guns can create a maximum of 10,000 psi force to make the lubricant flow. This gun is popular in mechanical places and garages for lubricating the joints of moving parts.

Some engines need only oils with high viscosity to prevent tool wear. So if you are thinking, “Do I need a grease gun or not?” then check for the zerk fittings in machines.

Because for the lubrication of parts like axel bearing needs grease guns to hold the thick greases. You will find lots of bearings and zerk fittings, so consider buying one.

How does a grease Gun work:

First, you have to know why it is called the grease gun to understand the working mechanism of this. With the trigger grip or lever, it looks similar to a gun.

The build-up compression generated by air, hand, or electric power pushes the grease flow to lubricate a specific point. These guns have spring in them to create the push and pull motion.

On the other hand, the pistol grip works as the trigger point of the pressure. But it kind of works in an automatic way in the case of an air-compressed or battery-sourced gun. 

Types of Grease Guns:

There are three types of guns depending on the power source such as air, manual pressure, and battery. The manual guns contain the other two types.

That’s why the total categories would be four. So here are the four types of grease guns:


Any user can manually operate the lever grease gun by pressing the piston. The amount of liquid depends on the applied force.

It doesn’t need any external device set up for managing the grease flow that comes out of the tip of the gun.

Pistol grip (manual):

The pistol grip gun works under the same conditions as a manual one does. But it contains an extra feature of a trigger instead of the lever.

Prime it for creating a build-up before the application of lubricant. This is one of the most commonly used guns for lubricating moving parts.


The pneumatic gun is more suitable for industries and factories with tons of machines. It has an external air compressor to convey highly forced air through a length of hose.


This grease gun works in the same mechanism as the other guns. The only dissimilarity is its source of power. As the batteries provide the power, it doesn’t need any manual or external force to push the grease out.

How to load a grease gun:

The steps of loading a gun are not the same for every kind. Like the cartridge one’s procedure is different than the reservoir gun.

Let’s see all the necessary information about loading these two types.

Loading a cartridge gun:

Nowadays guns with cartridges are more popular because of their easy loading quality. You will find this grease gun easily.

If you want to know how to load a grease gun with a cartridge, then here are the steps to follow:

Step 01:

First, you have to loosen the barrel up a little bit to remove the cartridge from the pump. After twisting it, you can easily pull the plunger back.

Step 02:

The plunger is placed at the opposite of the pump head. Now grab the handle and pull it all the way to the end to secure it.

With some guns, there will be a notch or it can go into a retracted situation to lock the plunger. As it provides the pressure for the grease flow to come out, you have to lock it properly.

Step 03:

After that, you will take the old canister out and throw it to create a place for a new one. Make sure the cylinder is clean for reloading. 

If the barrel is filled with a chunk of old grease, then keep a cloth or rag near to wipe the dirt. Clean the excess leaked lubricant and the gun head.

Step 04:

You will find two ends in the new cartridge. One is the metal end and the other one is the plastic end. You need to be careful about which end goes in the grease gun.

Remove the plastic end and push it down completely. Then the cartridge end and the barrel end will be sealed together.

Now, look at the open side. You’ll see a metal end that looks like a soda can head. Pull the ring and open it. 

Step 05:

Now for re-connecting the pump head with the cylinder, you have to screw the barrel back with the head. When it’s fully attached then rotate it two to three times backward for a specific reason. 

After tightening the lid of the pump head completely, unlock the plunger and push it into the cartridge. 

If you are wondering how do you fill a mini grease gun? Then you will be happy to know that the procedure is the same and even easier than the bigger one.

Step 06:

Lastly, check if it’s working properly before use. You will find a little nipple on the head of the gun, near the nozzle. Push that so that the trapped air can come out. 

Then wipe off the extra grease from that. Now press the lever or pistol trigger to pump out some lubricant. If it’s coming out pretty smooth and without breaks, then you are good to go.

Loading a reservoir gun:

Don’t worry about how to load a grease gun without a cartridge. Here are the steps for you to load the reservoir one.

Step 01:

You will have to unscrew the pump lid attracted with the applicator pipe to separate it from the barrel.

Step 02:

Then pull the plunger located at the end of the barrel down. Keep pulling it until the handle is locked to prevent the suction of lubricant at the time of loading.

Step 03:

Grab the empty side of the barrel to refill the grease from the bulk container. Make sure to clean the open end to avoid contamination. 

Now you have to insert the whole barrel into the big container. Gradually pull the handle back to draw grease.

Step 04:

Lock the T-handle, when the barrel is loaded. Now you can take the cylinder out from the container. Then clean the excess grease with a rag.

Step 05:

After that reassembled the pump head by rotating it or screwing the nozzle. Depends on the model that you have.

Then unlock the liver from the notch. But make sure that you should not push the handle before screwing the barrel completely.

Step 06:

These instructions will give you an idea about how to load a grease gun from bulk. But you have to recheck the gun before using it in the same way as the previous step no 06.

Priming the grease gun:

Are you wondering, “why is my grease gun not working?” Then probably you’ve created air pockets in your gun.

Air-locking is a very common problem that can occur at the time of inserting a new cartridge or filling grease. Here are the things that you need to be careful about:

  1. After installing the new cartridge, assemble the barrel again with the pump head. Continue rotating until the lid is fully closed. Then simply unscrew it in the opposite direction two to three times.
  2. Push the nipple head to release the trapped air. 
  3. Be careful before filling the barrel manually through a container. To avoid air pockets, push the lubricant again in the container and pull it again to reload the gun.

Pro tips:

  • Choose the correct type of lubricant for applying in specific parts.
  • It would be best if you use the same grease to avoid chemical reactions as the barrel may contain grease leftovers.
  • Make sure to clean the pump head and fittings before loading.
  • When you are done with the work, keep the gun in a cool place to prevent oil separation.
  • Don’t store it vertically after finishing the lubrication.
  • Wrap the nozzle to avoid contamination.

Final Verdict:

Almost every machine parts and fittings need lubrication to achieve sustainability. That’s why you will find grease guns in any machine shop.

So this article will help you to understand how to load a grease gun correctly. I hope this was beneficial for you. Also, we reviewed a few best grease guns currently available on market. check this article if you need one.