kubota kx71

[v8druid]

some machines are actually spec.ed with engine oil used as hydraulic ... trying to think of an example -- think some Komies were
........ never heard of a mix though ..... what oil is spec.ed for that Kub Gordon ....... and have you sussed any pressures yet

[Muz]

It would just cause frothing in that machine and not give any productive benefits imo... Have only ever seen universal oils in tractor hydraulics .....however every day is a school day

[gordon macritchie]

hyd oil #46 is the oil spec

no idea what mix oil to hydraulics that he used
no havent got pressures checked yet will need to find a fitter to do this for me
the machine was parked up for close to two years before i got it so could be something seized or sticky in the system?
filters arrived today so hopefully get that done soon

[Muz]

should be Aws 32 spec . Engine oil has very different properties to hydraulic, hydraulic is not compressible and its viscosity varies very little with temperature unlike engine oil, I personally would not put it anywhere near that type of hydraulic system, when you get trapped air,(which you'll get by mixing) it leads to all sorts of other issues.

[2414.ginger]

I think he is going to need to drain and refill 2/3 times to get rid of what is in there now.
Is there any rinsing oil, or something on the market that would speed up the process?
Do you think that this is the main cause of his problem?

[Muz]

I think he is going to need to drain and refill 2/3 times to get rid of what is in there now.
Is there any rinsing oil, or something on the market that would speed up the process?

Not that I'm aware of .. a simple drain down of all rams orbital valve and tank will remove 90 odd %

Do you think that this is the main cause of his problem?

quite possibly .. it will certainly have some effect because air bubbles are highly compressible, and result in jerky movements, with poor performance

[v8druid]

so this machine has a bastardised mix of hyd and engine oil in it ?????

Ain't gonna be helping the cause for sure, but ..... OP isn't describing jerky, just dog slow operation ????

As said ..... that is going to take some getting out of the machine and is going to need some very thorough, methodical removal ....... even then !!!

[gordon macritchie]

as far as i know its just normal hydraulic oil in the machine, i was just told by a fitter this is something they used to do, will hopefully get the oil drained tomorrow and get some fresh oil in

[Muz]

as far as i know its just normal hydraulic oil in the machine, i was just told by a fitter this is something they used to do, will hopefully get the oil drained tomorrow and get some fresh oil in

That may not be neccessary and just gives you extra cost, if it isnt frothing, and you havent added anything to it just leave it

[v8druid]

agreed Muz ...... get the filters done and if the oil looks clean enough and not frothing .... leave it in there ..... Please ... get the pressures checked though ..... it will at least give some idea of where to start

[gordon macritchie]

got one filter done yesterday still waiting for other one to arrive, think it was the flow filter just a gauze really, it was very dirty, oil didnt look too bad so have just left it, got the water changed and the system cleaned out, will find out next week if its running better

has anyone used one of these before,