I thought this might be worth mentioning because the extending dipper
is so prone to getting loose or sloppy. I usually have to mention in my machinery inspections that the extending dipper needs tightened up. With the JCB extending dipper, I’ll usually find that they come in tight or are fairly easily adjusted to be tight. So I like the design…
Around 1988 JCB came out with this extending dipper design. I now notice that Komatsu and New Holland have very similar designs and for good reason. Anyone who has repaired a loose extending dipper will appreciate it.
Looking down the side of the dipper notice the 4 bolts, behind each of the bolts is a shim pack. Removing a shim at a time and reinstalling the bolts moves a wear plate in closer to the extending section of the dipper. When the shims are gone the wear plate is replaced, (without breaking down the extending dipper), the shims reinstalled and the dipper is tight as new again. No welding, no plating, and a very easy repair. Watch for loose bolts on the top side of the dipper, digging pressure is exerted against the wear strips that the top bolts hold in so the bolts can work loose. Then the wear strip can fall out. Keeping them tight eliminates that issue. The last picture is difficult to see because of the grease but the lower wear strip is right behind the tapered section and when the machine gets in I will clean the grease away so it can be seen.
Also around 1988 I was touring the JCB factory in England, a totally unassuming older gentlemen, walking through one of the engineering departments stopped by our group and shook all of our hands and thanked us for coming by and asked if we were all fed well. Mr. Joseph Cyril Bamford, JCB.