GX CS4

[Sawney Bean]

All this talk about the kind of grease. I'm curious to know just where does the grease end up? If you aren't forcing it into the top of the compressor when you turn the pot screw how does it get "sucked" into it without it sucking ALL the grease into it at one time? Folks say the grease never gets down to the bottom around the crank or rod so I'm assuming that would need to be greased by hand? Which would require taking it apart.

Thx
Ray

The grease pot appears to feed the pistons and cylinders of the compressor. The pot itself is basically a piston and cylinder with a small hole in the bottom of the cylinder for the grease to flow into the pump and the piston is driven by the feed screw. There's a floating rubber baffle in between the bottom of the cylinder and the piston that is there to regulate the flow of lubricant into the pump. So when there's no pressure on the grease the rubber baffle should stop the grease from entering the compressor, but when you tighten the pot screw it should force grease in somehow.

Looking at it, it does not seem like something that would work well. Intuitively it seems like the baffle would block the flow of grease whether it was under pressure or not. On my own pump the baffle seemed to be partially submerged in the grease within the cylinder. Having removed the baffle and run the pump though I can say that the next time that I inspected it afterwards the grease pot was empty. So it appears that the baffle was indeed stopping the flow of grease.

The bearings on the crankshaft down below are completely isolated from the grease feed up above. They were relatively easy to get at though and I can't see any reason why they would require special grease.

 

[F6Hawk]

All this talk about the kind of grease. I'm curious to know just where does the grease end up? If you aren't forcing it into the top of the compressor when you turn the pot screw how does it get "sucked" into it without it sucking ALL the grease into it at one time? Folks say the grease never gets down to the bottom around the crank or rod so I'm assuming that would need to be greased by hand? Which would require taking it apart.

Thx
Ray

The grease is too viscuous to be sucked into the piston, hence the turning of the grease pot knob.

The cylinder assembly is sealed at top and bottom, so no, grease cannot get to the crank bearings; these must be lubed by hand. Having had mine apart on day one, there is enough grease on them to last for years, I'd reckon.

The only place for the grease to escape is thru the bleed port and into the air hose to be trapped by a filter. As I bleed during fills, I get a little bit of water as well as some black grease coming out.

 

[Sawney Bean]

The grease is too viscuous to be sucked into the piston, hence the turning of the grease pot knob.

The cylinder assembly is sealed at top and bottom, so no, grease cannot get to the crank bearings; these must be lubed by hand. Having had mine apart on day one, there is enough grease on them to last for years, I'd reckon.

The only place for the grease to escape is thru the bleed port and into the air hose to be trapped by a filter. As I bleed during fills, I get a little bit of water as well as some black grease coming out.

I'm guessing the amount of grease on the crank bearings depends on who assembled the compressor. I found mine were bone dry after hearing a loud squealing sound coming from the compressor and tracking the noise to the bottom end.

 

[ray1377]

Looking at it, it does not seem like something that would work well. Intuitively it seems like the baffle would block the flow of grease whether it was under pressure or not. On my own pump the baffle seemed to be partially submerged in the grease within the cylinder. Having removed the baffle and run the pump though I can say that the next time that I inspected it afterwards the grease pot was empty. So it appears that the baffle was indeed stopping the flow of grease.

So the baffle "DOES" do something then? Without it the grease would get inside the compressor even if you don't turn the grease pot screw so I guess that dinky rubber part does work as intended. It seems like a simple design but it does work I guess.
Thx
Ray

 

[ray1377]

The grease is too viscuous to be sucked into the piston, hence the turning of the grease pot knob.

The cylinder assembly is sealed at top and bottom, so no, grease cannot get to the crank bearings; these must be lubed by hand. Having had mine apart on day one, there is enough grease on them to last for years, I'd reckon.

The only place for the grease to escape is thru the bleed port and into the air hose to be trapped by a filter. As I bleed during fills, I get a little bit of water as well as some black grease coming out.

I've only gotten moisture from mine so far. No grease or dark stuff that I've seen yet. I haven't taken mine apart cause its just got a little over 2 hours on it. I do have a habit of putting a paper towel down below the drain line so I can see if there is anything coming out other than moisture when I bleed the system.
I've got an inline filter between the compressor and the fill hose end. I check it after every use and it has not had any moisture make it down the hose to that filter yet. I'm pleased with it so far. I did add an external digital temp sensor to the pump head next to the factory sensor. I like to be able to "KNOW" how hot it is when its running. Also added LED lights to the water tank so I can see the pump working without having to remove the tank cap while it's pumping. I also 3D printed a bracket to fit over the pressure gauge and it has a LED in it pointing down to light up the gauge housing so I can see it better. And finally I put on an hour meter to keep track of run time.
Thx
Ray

 

[Sawney Bean]

So the baffle "DOES" do something then? Without it the grease would get inside the compressor even if you don't turn the grease pot screw so I guess that dinky rubber part does work as intended. It seems like a simple design but it does work I guess.
Thx
Ray

That was indeed my experience. It looks like something that shouldn't work, but it actually does seem to do what it was intended to.

 

[F6Hawk]

I've only gotten moisture from mine so far. No grease or dark stuff that I've seen yet. I haven't taken mine apart cause its just got a little over 2 hours on it. I do have a habit of putting a paper towel down below the drain line so I can see if there is anything coming out other than moisture when I bleed the system.
I've got an inline filter between the compressor and the fill hose end. I check it after every use and it has not had any moisture make it down the hose to that filter yet. I'm pleased with it so far. I did add an external digital temp sensor to the pump head next to the factory sensor. I like to be able to "KNOW" how hot it is when its running. Also added LED lights to the water tank so I can see the pump working without having to remove the tank cap while it's pumping. I also 3D printed a bracket to fit over the pressure gauge and it has a LED in it pointing down to light up the gauge housing so I can see it better. And finally I put on an hour meter to keep track of run time.
Thx
Ray

Perhaps you "haven't yet", but you will see the dark grease coming out. It has to, as the air line is the ONLY place it can go.

I took mine apart the day I got it. The engineer in me wanted to see "what makes this tick?". And I shared it so others wouldn't have to do the same.

2024 CS4 SETUP

So I received my CS4 on 19 Feb 2024. Took the case apart to install an hour meter (which didn't work like I wanted it to, so ordered a different one). Removed the small pre-filter and installed my homemade one with color-changing silica beads in it. (Two 3/4" PVC caps, tube wrapped with...

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