Ex60-3 final drive filling with hydraulic oil

[cjmc]

hi all,
First post here,
Have a hitachi ex60-3, have one of the final drives in the track motor filling up with hydraulic oil.
From time to time when I go to check the level, there is pressure in the final drive when I open the level plug and a full flow of oil comes out for a few seconds, the other side is at the correct level when I check it and there is very little, if any, pressure on the plug.
The oil on the overfilling side also tends to be quite metallic in appearance, I presume this is due to the hydraulic oil thinning the gear oil in the final drive and not providing the correct lubrication.
I recently changed the seals on the Centre joint as the machines tracking power had gotten very weak on one side, to the point that it would be impossible to track the machine in a straight line.
I did find a couple of the seals badly damaged, and the tracking power and straightness is now good since I changed the seals.
I’m wondering What do you think is the cause of the final drive filling up, duo cone seals?, motor shaft seal?, brake piston seals?
There is also no trace of oil leaking externally around the motor or final drive.
Would be interested in hearing your thoughts.
Thanks
Cjmc

 

[rgl726]

you need to replace your brake piston seal

 

[cjmc]

Thanks for the reply,
Can the motor be removed from the final drive in situ and the seals replaced or does it all have to come out?
I removed the track motor covers there a while ago just to clear away any dirt and to confirm there was no oily dampness around the final drive or motor, all dry as a bone, but I did notice the heads for the bolts that hold on the whole assembly to the undercarriage are badly corroded, whereas the 6 Allen key head bolts that bolt the motor to the drum are in good shape..

 

[rgl726]

 

[cjmc]

Thanks for the diagram, is it o ring no.35 I need so?, or are there more seals that I need, 24?,36?,

 

[rgl726]

The d ring 36 and 38.
Others are just o rings

 

[cjmc]

Thanks, I suppose I would be as well to get o rings 24 and 35 as they will be exposed when I split the motor from the hub?

 

[rgl726]

Yes better if you replace it also