Hitachi EX150LC Issues

[Bruce Hill]

Hi all,

I just acquired an EX150LC Hitachi, and I'm losing substantial amounts of hydraulic oil through the swing motor (bleeding through to the turn table ring gear).

I will be pulling the swing motor tomorrow, figuring it is a seal of some sort. There is no differential oil showing on the dipstick, but it is definitely hydraulic oil that I am losing. Advice, please.

-Bruce

 

[TVA]

One advise - make sure you loosing oil through the motor and not through hose fittings or even center pivot/rotary manifold. Might just save you money!

 

[uffex]

Good day Bruce
There are a couple of possibility's one you may have overlooked is the central passage, some machine can leak hydraulic fluid into the turn table chamber, its strange you have no hydraulic fluid in the swing transmission, I attach a picture of the 120 but I believe it is similar.
Kind regards
Uffex

 

[Bruce Hill]

One advise - make sure you loosing oil through the motor and not through hose fittings or even center pivot/rotary manifold. Might just save you money!

It is dry above and around swing motor. Central passage ? Center pivot/rotary manifold ? Would you please explain ? Thank you for your input !

 

[Bruce Hill]

One advise - make sure you loosing oil through the motor and not through hose fittings or even center pivot/rotary manifold. Might just save you money!

This central passage you are referring to, is the same as the Center pivot/rotary manifold ? Where is this located ? Is this part of the swing motor ? What lays just ahead ( toward the front) of the swing motor. It has a couple of Hyd lines to it. The swing motor appears to have been replaced or rebuilt at some point. Newer unpainted bottom half. This type of issue is a first for me. So is the Hitachi.

 

[Bruce Hill]

One advise - make sure you loosing oil through the motor and not through hose fittings or even center pivot/rotary manifold. Might just save you money!

Where is the center pivot rotary manifold you are referring to?

 

[TVA]

Where is the center pivot rotary manifold you are referring to?

That’s the thing right smack in the middle of turret, the Oil passage to motors, swing motor usually in front of it.
Yes you have hoses going to it on top and from it to motors underneath.

 

[uffex]

Good day Bruce
The central passage is right in the centre of the machine, if you follow the hose or tubes from the valve chest you will find a bunch of four arrive at the very centre of the machine, this also is known as rotary coupling - rotary manifold .
We will try and find a map if you need.
Kind regards
Uffex

 

[uffex]

Good day
Explanation

 

[Bruce Hill]

That’s the thing right smack in the middle of turret, the Oil passage to motors, swing motor usually in front of it.
Yes you have hoses going to it on top and from it to motors underneath.

Is it most likely that my hyd oil is coming from the rotary manifold ? Is there a method of determining what I should tackle first. I am leaning toward the removal of the rotary manifold first. Leaking this much hyd oil should be pretty obvious ?

 

[uffex]

Good day Bruce
Its a dirty job but crawl beneath the machine look up at the underside of the centre passage if you can see fluid this is where you need to be.
KR
Uffex

 

[uffex]

Good day an actual illustration we found maybe it helps.
KR
Uffex

 

[Bruce Hill]

We were underneath and yes all your input has been very useful. The unit has been sitting idol for several days. When looked at more closely, we found hydraulic oil dripping from the turret ring gear. I belieive it was said earlier that it is likely this has accumulated most likely from the area around the rotary manifold ? We are going to remove the rotary manifold and have a look. Wish me luck. If you think of anything more, I am all ears .

 

[Bruce Hill]

One advise - make sure you loosing oil through the motor and not through hose fittings or even center pivot/rotary manifold. Might just save you money!

Are you refering loosing oil through the swing motor ? Is this common ? Is it more heard of that the center pivot rotary manifold needs to be rebuilt ?

 

[Bruce Hill]

Good day Bruce
The central passage is right in the centre of the machine, if you follow the hose or tubes from the valve chest you will find a bunch of four arrive at the very centre of the machine, this also is known as rotary coupling - rotary manifold .
We will try and find a map if you need.
Kind regards
Uffex

Dear Sir
I had mentioned earlier in this thread that there was little to no differential oil in the swing motor. I would like to know if this possibly is an indication how hydraulic oil might be finding it's way to the turrett pan causing me to loose substantial hyd oil. Most of our focus has been on the center joint of which we had pulled last night. We plan on tear down and new seals etc., however having found not oil in the swing has given me questions. I put differential oil in to see if it would maintain proper level while rebuilding the center joint manifold. Would this give me any indication whether or not I should pull this as well ??

 

[uffex]

Good day Bruce
We are a little confused by your terminology so we will try to clarify, the motor transmission illustration above item No.10 is the motor this is driven and lubricated by hydraulic fluid, for the fluid to make passage to the swing ring it has to fill the transmission that is below item No.10. The transmission should have light gear oil to lubricate the planetary gears. If the gear oil is present at at the correct level the issue is not from these components.We cannot find any other possibility for hydraulic fluid to enter the swing ring.
I should add fluid will normally flow from the dip stick when the motor shaft seal leaks.
Kind regards
Uffex

 

[uffex]

Good day Bruce
A contact sent an extract sorry the quality is not so good but it may help.
Kind regards
Uffex

 

[Bruce Hill]

Good day Bruce
We are a little confused by your terminology so we will try to clarify, the motor transmission illustration above item No.10 is the motor this is driven and lubricated by hydraulic fluid, for the fluid to make passage to the swing ring it has to fill the transmission that is below item No.10. The transmission should have light gear oil to lubricate the planetary gears. If the gear oil is present at at the correct level the issue is not from these components.We cannot find any other possibility for hydraulic fluid to enter the swing ring.
I should add fluid will normally flow from the dip stick when the motor shaft seal leaks.
Kind regards
Uffex

I am loosing oil from the dipstick. What kind of job is required then to repair the motor shaft seal ? I have pulled the center joint rotary manifold and am awaiting seal kit. It is assumed then that this issue is a combination of loosing differential oil through the rotary shaft seal (not hydraulic from drive above) and the rotary manifold (hydraulic) center joint, into the swing ring. Is this correct in your opinion ?
Sincerely
Bruce

 

[uffex]

Good day Bruce
Oil from the dip stick we assume is thin like hydraulic fluid if this is the case the swing motor is the culprit, if the shaft seal leaks it will drain into the the transmission (Should be gear oil) and the making passage into the swing ring bath. If this as we outline above leave the rotary shaft coupling, remove the swing motor renew the shaft seal - change the case drain filter as this could be the beginning of the seal failure. We suggest you pull the transmission and change the seal also.
If you can confirm that we have interpreted the situation correctly we will put some information,ation together for you.
Kind regards
Uffex

 

[TVA]

I would remove the whole assembly and replace seal on the bench. Because it’s really problematic to do it correctly and cleanly in place.

And I would look for reasons why seal failed, high case pressure caused by restriction in case drain hose or filter, wobbly shaft caused by failed bearing or bushings, or rough sealing surface of the shaft.


If you decide to do it in place at least pressure wash surroundings of work area really good, before starting disassembling anything, so when you will be working the dirt will not be falling in.