Dangers Of Turning Up the Hydraulic Pressure on Your Excavator.

Machine seems just to small for the job, just need to lift that little bit more,or maybe you feel your machine is a little tired?

The fastest and easiest way my seem to be also the simplest answer.

YES - Bump up the hydraulic pressure in the system. Adjust the pressure relief valve.

But is that relay the answer?  What dangers lurk in bumping up the pressure on any machine?

Well you be the judge and consider the evidence presented.

The Importance of Check Valves in Hydraulic Systems

Please click on the image below and read a very informative article explaining the need to respect the pressure relief valve and not mess with it.  Full Stop.

In the next image consider all the hydraulic seal that will come under additional pressure after we have bumped up the system pressure.

Here we have the rod collar an the piston from inside the hydraulic cylinder.

Notice the damage to the O rings and pressure seals.

 The O rings look like they are perished, or got pinched or damaged during assembly.

Not the case.

 In this photo the O rings look like they have had heat or fire damage.

Not the case.

 Another shot.

Event the tough pressure seals on the piston have degraded and have splits and cracks in they.

New seals fitted and fitting the piston to the rod.

This is how seal should present.

Case Lesson - Keep to the manufactures specifications.

Keep hydraulic system pressure the designed and save yourself heaps of time and money.

Excavator Bucket Pin Re-positioning.

Object of the exercise. - To reposition the pins and bushes on the excavator bucket so that they can be attached to a machine with a smaller distance between the attachment pins.


In the illustration below, that would be the distance between "c"  and the diameter of "a".

In this image the blue bucket has been modified while the one behind still need the conversion.

The first thing to do is to remove one set of bushes by grinding away the welding keeping them in place.

One bush removed successfully , one more to go.

 The same process needed to be done to all the implements, including the pick

Next came the interesting part, turn some new bushes that have an eccentric hole in them, With some trusty mathematical skills this not difficult, and so work began.

Machining the eccentric hole into the new bush. the outer diameter has not yet been cut to size.

Bushes completed and ready to be welded into place.

A little more material prep and we are ready to fit the new eccentric bushes.

Notice the locating step cut into the outside diameter of the bush, this would help tremendously in lining  up the whole  set-up. Simply turn the new eccentric bush until the desired distance is achieved.

New pins - bushes and all welded-up/

 Holes drilled for the bolts that lock the pins in place.

Job completed on the pick - ready to work.

End product, light lick of paint and away we go!

Side view of how the eccentric bush and pins can change the distance between pins without modifying the bucket structure.

Excavator Dipper Arm Repair - Bush Replacement.

The dipper arm on any excavator takes a lot of punishment, 

Even with good lubrication an regular servicing something has to wear-out.

on this Kobelco SR35 the time has come to have the bosses machined out and replaced with new ones.

After removing the dipper arm from the excavator, the arm was secured to the mill bed.

Some rough cuts to make way for the new bosses.

 Final machine cut to size.

Machining the opposite end.

 Turning the new boss that will be pressed into the dipper arm.

This approach was adopted because the boss and bushes were so badly worn that simply replacing the bushes would have made no improvement.

Boss turned and ready to be pressed into the dipper arm.

New bush that runs inside the boss.

All pressed together and in the bottom you can see the new bush.

Dipper arm like new.

Only one way - the right way.