Grease Flow in Ball Joint, Path of Least Resistance?

[JohnSmith0909]

Ball joints have different sealing mechanisms.
1. The boot just rests on top, and is not sealed at all at the bottom or top of the boot.
2. The top part of the boot only is sealed via a
A. lip and groove mechanism that allows old grease to be pushed out from the top and bottom
B . Retaining ring, old grease cannot be pushed out from the top, and must be expelled from the bottom of the boot
3. The bottom part of the boot only is sealed via a lip and groove mechanism or retaining ring
A. lip and groove mechanism that allows old grease to be pushed out from the top and bottom
B . Retaining ring, old grease cannot be pushed out from the bottom, and must be expelled from the top of the boot
4. The top and the bottom part of the boot only is sealed via a lip and groove mechanism or retaining ring
A. lip and groove mechanism that allows old grease to be pushed out from the top and bottom
B . Retaining ring at the top and bottom, old grease cannot be pushed out via pin hole opening within the boot from the manufacturing process to allow old grease to be expelled.

All greasable options above allow for dirt, water, grime, sand etc, to enter the ball joint shortening it's life. Option 4B is the best at keeping contaminants from entering the joint, but it's still not perfect. Is there a better option than 4B?

Option 4, but instead a pin hole opening within the boot, what if a outlet is drilled into the body of the ball joint. Would the old grease at the top of the boot remain at the top and never get bushed out? Would the grease just travel just the shortest path from inlet to outlet? Meaning something like this:

A second hole (orange) within the ball joint that allows old grease a path out. It can be plugged when not greasing the joint to keep contaminants out. New grease enters via the zerk fitting (blue). Would the new grease just follow the path of least resistance (yellow line) and take the shortest path from the inlet to outlet? Effectively not allowing the new grease to spread throughout the joint, and the old grease would remain within the joint?

You can see that the ball joint above is option 4B, with two retaining rings. There's no way for old grease to be expelled from the joint, but it likely has a pin hole opening from the manufacturer to allow the old grease out. If this hole didn't exist, the grease would be stuck within the joint, and would effectively be a sealed ball joint.

Thanks for the help!

 

[Baluncore]

While being greased, the older grease should exit under a spring clamp that holds the rubber boot in place. The boot and clamps form a one way valve, that lifts to allow excess grease to vent, without blowing off the boot.

Avoid all pinholes.
The sealed nature of a joint means that it does not contain environmentally contaminated grease. The rubber boot has a variable capacity, so there is no tidal flow of grease, dirt or water, during normal operation.

 

[JohnSmith0909]

While being greased, the older grease should exit under a spring clamp that holds the rubber boot in place. The boot and clamps form a one way valve, that lifts to allow excess grease to vent, without blowing off the boot.

Avoid all pinholes.
The sealed nature of a joint means that it does not contain environmentally contaminated grease. The rubber boot has a variable capacity, so there is no tidal flow of grease, dirt or water, during normal operation.

Hi, thanks for the reply. The first time that I have "overfilled" a ball joint, the boot just kept on expanding to the point of rupture. Eventually a hole is formed in the boot from the rupture. Allowing contaminants to enter the joint.

The second time I overfilled a ball joint, the boot expanded to the point where the spring clamp could no longer clamp the boot onto the stud, resulting in the boot just eventually pulling out from under the spring clamp. This resulted in permanent deformation of the boot from over expanding and the clamp being damaged.

I was hoping for an option that I wouldn't have to worry about deforming the boot or rupture.

If I drilled a second hole (orange) that I left open while adding grease, and inserted grease via the zerk fitting (blue), would the grease just travel the yellow path, the path of least resistance? Resulting in the majority of the grease being within the boot being old grease. I could insert a "plug" into the orange hole while not greasing, creating essentially a sealed joint, while still being able to add fresh grease.

I was also wondering, any idea what the technical term is for these clamps (purple)?

When the joint was overfilled and the boot eventually just pulled out from under the clamp, the clamp was deformed. Hoping to just get replacement clamps, but I'm not exactly sure what these clamps are called. They are kind of like key chain loops. Was hoping to buy just the clamp, and like a bunch of them. Kind of similar to buying an assortment of bolts, buy an assortment of these clamps. Also any idea if there's special pliers to expand this type of spring clamp? Doing it with a screw driver is a real pain. I know that snap ring pliers won't work with this type of clamp.

Sorry for all the questions.

 

[Baluncore]

The first time that I have "overfilled" a ball joint, the boot just kept on expanding to the point of rupture.

When the joint was overfilled and the boot eventually just pulled out from under the clamp, the clamp was deformed.

Replace any joint with a damaged boot. Damage is indicated by the presence of lubricant outside the boot. If the boot contains grease, and remains sealed, then do not inject more grease. That is an unnecessary path to destruction.

Do not employ a pinhole as a vent. Air and water can pass, but the hole will be too small to allow grease to escape at the rate you can inject new grease. Every time a joint moves, the pinhole will allow the joint to breathe air, dirt and water into the joint capsule, contaminating the grease and destroying the joint surfaces.

Joints that are to be regularly greased will always have a lip seal that allows the excess grease to escape.

I was also wondering, any idea what the technical term is for these clamps (purple)?

That is a boot retaining spring. They are not available without the boot they were designed to clamp. You might make one from piano wire.

If you need to grease a sealed joint, then lift a seal to allow the old grease to escape. Some boot retaining springs are made from piano wire, others from long thin spring loops. You can always pick out a spring clip with a small hook tool, made from steel wire, such as an old bicycle spoke, or an older spring clip.

Sufficient grease is good. Too much grease is bad.
When you hold a hammer, everything looks like a nail.
When you hold a grease gun, you must show restraint.

 

[sophiecentaur]

When you hold a grease gun, you must show restraint.

Bursting a seal was a common problem. The use of 'sealed for life' has reduced the number of failures in my life to (near enough) zero. My comparison is between similar types of domestic vehicles and nothing high performance.