Hydraulic oil, changing and flushing system ?
Posted: Tue Oct 31, 2017 10:47 pm
Hi Guys,
I am now at the stage in my restoration of my Hitachi EX27u where I am tackling the hydraulic pipes and oil.
The oil has never ever been changed on this m/c, the service interval is 3000 hours and it has 3220, so I guess the previous owner wasn't too bothered.
However, the oil never having been changed nor inspected nor water drained off, is in a shocking state , this I guessed when I bought the m/c so am not greatly bothered as I intended to drain the system down, replace all filters and put in new oil.
So, having removed a couple of pipes I deemed could do with replacement, I drained some of the existing oil into a jar to see what it was like - see pix. This sample came from one side of the boom, pipes that feed the pecker! About 2meter of pipe !!.
My question are: Given that I need to drain all of the oil/water completely from the system, and draining won't be a problem, what I am concerned about is making sure that when I refill the tank and start the pump I am A: not going to cause damage with a possible dry pump !! B: that I am going to get all of the water (emulsion) out of the system and C: also I do not want to create air blockages.
Could someone suggest a table of events or a logical order for me to follow, or any hints or tips. Time is not a problem, so can fill the tank and let it rest for however long is necessary etc. Slacken off far end of a run to bleed air etc, just need a point in the right direction
Cheers
John
I am now at the stage in my restoration of my Hitachi EX27u where I am tackling the hydraulic pipes and oil.
The oil has never ever been changed on this m/c, the service interval is 3000 hours and it has 3220, so I guess the previous owner wasn't too bothered.
However, the oil never having been changed nor inspected nor water drained off, is in a shocking state , this I guessed when I bought the m/c so am not greatly bothered as I intended to drain the system down, replace all filters and put in new oil.
So, having removed a couple of pipes I deemed could do with replacement, I drained some of the existing oil into a jar to see what it was like - see pix. This sample came from one side of the boom, pipes that feed the pecker! About 2meter of pipe !!.
My question are: Given that I need to drain all of the oil/water completely from the system, and draining won't be a problem, what I am concerned about is making sure that when I refill the tank and start the pump I am A: not going to cause damage with a possible dry pump !! B: that I am going to get all of the water (emulsion) out of the system and C: also I do not want to create air blockages.
Could someone suggest a table of events or a logical order for me to follow, or any hints or tips. Time is not a problem, so can fill the tank and let it rest for however long is necessary etc. Slacken off far end of a run to bleed air etc, just need a point in the right direction
Cheers
John