Importing and modifying a new mini excavator from China

[dfkrug]

If and when the bushing rotates, the grease stops.

Correct. The sleeve bearings are interference-fit, so probably will not rotate. Neglecting
a pin that does not take grease can eventually cause the sleeve to rotate, yes.

The best solution is to use a bored pin with protected zerk fitting in the end. My Bulgarian
backhoe has those.

 

[dfkrug]

With the correct needle, greasing is very easy, compared to standard zerks.

I do not have much experience using the needle grease fittings. We all have needle-grease ports on our
chainsaw bar sprockets, but I use oil there, not grease.

I want to use the same gun and grease for everything, and do not want to have a second gun full
of grease.

On the replacement cyls I bought, the grease fittings have the dished tops like yours. I do have
a needle grease fitting for my Lincoln electric grease gun....never used it.

 

[bindian]

Those flush fittings and the adapter do not look workable for sure.

I had to experiment a bit but now use this type of flush fitting (both threaded and tap-in). They need to be used with a matching Lincoln grease needle. With the correct needle, greasing is very easy, compared to standard zerks.

Never seen a flush fitting on heavy equipment. Only on our Boeing 737s. I hate them. They are a quick way to put grease in your eye, hair, or face. They don't lock on, so if there is hardened grease, you will squirt grease out at an angle, usually on yourself.
hugs, Brandi

 

[dfkrug]

Never seen a flush fitting on heavy equipment. Only on our Boeing 737s. I hate them.

That is interesting, Brandi. I realize that aviation is a different world. Why do you suppose flush-face
fittings are used there?

 

[dfkrug]

This is a spare bucket cylinder that I got with my shipment. Note the dished needle-grease
fitting. The other needle-grease fittings on my XN08 all had flush-face fittings. Maybe you
can position your grease gun at a slight angle with the dished fittings?

Anyway, this cylinder will go towards my custom hydraulic thumb, if I do not use a leftover
cyl from another project. At least I know the IDs are the same. i.e. the bucket cyl and
the thumb cyl will be matched.

Note that this cyl has paint on the replaceable sleeve bearing. It seems to be made of all-metal;
no nylon or Teflon coating. I will remove the paint before using.

 

[dfkrug]

Here is a strange thing I came across when analyzing my new machine: one of the bucket links
is not welded to its bosses. Its mirror-image on the other side is welded as you would expect. You
can see the latter in the 4th photo of post #67.

I sent the attached photo off to China with my question. Their response on the photo (in red), and email
made no sense to me.

I have since welded the bosses, but my paint job is not even close in color.

 

[downsizingnow48]

They must consider those to be collars, not bosses.

 

[dfkrug]

They must consider those to be collars, not bosses.

Look at the other side, Pat.

Regardless of what you call them, the links will wear out fast if allowed to rotate on their
respective pins. The bosses and bolts stop that rotation.

 

[downsizingnow48]

I agree completely on welded bosses a better way to go.

 

[bindian]

That is interesting, Brandi. I realize that aviation is a different world. Why do you suppose flush-face
fittings are used there?

Clearance issues. They are used where zerts would get knocked off. Like door hinges where the snubber or guide arm would hit the zerts when the door is closed and the parts nest on each other. Or flight controls where the part the fitting is on (in?) moves under another part.
hugs, Brandi