The CS4 Grease Pot – How to add grease to your compressor and refill the pot

The GX CS4 is a very cool compressor and one of the two ways it gets the long run time is through staying properly greased. (The other is through the use of fluid coolant that I covered in a blog post about setting up and testing the unit). After 4-6 hours of compressing air with your GX CS4, you are supposed to given the top grease pot knob one full turn. How does that work and how does one refill it?

Adding Grease Every 4-6 Hours

It’s simple, turn the top knob one full turn to introduce grease. You may be wondering why I even bothered adding a blog post. The reason is that when I turned the knob there was so much resistance that I thought the pot was empty – it wasn’t. What I want you to see is why there is resistance:

To add grease, you turn the top knob with the arrows one full turn clockwise. The problem was that mine stopped right around 3/4ths of the way around. I thought maybe it had been shipped without the grease pot being filled.
To remove the grease pot simply turn the lower portion of the pot counter-clockwise and it will unscrew. It then lifts out.
Well, it was definitely full. I can honestly say I have never seen a grease with this color and texture. Note the black thing down in the very bottom of the pot.
It’s a simple mechanism. You turn the pot counter-clockwise to cause the plunger to move to the top so you can fill it. Or, you turn it clockwise, the plunger comes down and it pushes grease in … or at least it should.
There was a black disc down in the pot / the chamber the pot threads into depending on how you want to describe it.
I fished the black disc out using a finger, wiped it off and there was a very small hole in the middle. The black disc is a flow limiter! Now I understand why there was resistance! What this tells us is that you can only turn the screw so much and the limiter will cause resistance. So, turn the top screw until it stops and run the compressor. You can turn the screw on the pot the rest of the way as the grease goes into the mechanism but do not introduce more than one full turn worth of grease.

Refilling the Pot

Well, I had really made a mess playing around with the grease pot and lost most of the grease in the process. I asked the Amazon seller, Ankul, what I should use and he told me to go with a general food grade grease. I asked if silicone would work because that seemed to be the composition of most, if not all, food grade greases on Amazon and he said “yes”. Based on that, I ordered a tube of the below Haynes Silicone Grease off Amazon due to it’s good reviews. The important part for you to bear in mind is to go with food grade and I assume this is to protect the seals or something.

This Haynes grease has very good reviews on Amazon so I went with it.
I turned the knob counter clockwise and screwed the plunger all the way to the top of the pot and then topped off the pot with the silicone grease and screwed the pot back into the compressor.
Once it was installed, I gave the top knob a turn, ran the pump for a minute and then turned it the rest of the way.


In hindsight, it is very straight forward but I didn’t expect the flow limiter to stop the knob from turning and I didn’t know what grease to use to refill the pot so it seemed like good info to share.

I hope this helps you out.

Note, I have to buy all of my parts – nothing here was paid for by sponsors, etc. I do make a small amount if you click on an ad and buy something but that is it. You’re getting my real opinion on stuff.

If you find this post useful, please share the link on Facebook, with your friends, etc. Your support is much appreciated and if you have any feedback, please email me at Please note that for links to other websites, I may be paid via an affiliate program such as Avantlink, Impact, Amazon and eBay.