JD 690E LC How do I determand if the Hyd leak is the rotary swivel or swing motor?

[LOFAYTX]

I bought the JD 690E LC. It has a bad hydraulic leak under the rotary table. How do I tell if the leak is from the rotary swivel in the center of the machine or the swing motor seal?

Would the machine still move correctly with some of the rotary seals leaking?

 

[mclean]

Which component is leaking?

Pull the track frame pan off and see if the swivel is wet. Or a hose has popped?

Chris

 

[jaytech]

check the dip stick for the swing motor
if its full and holding then its your swivel joint

 

[LOFAYTX]

I put 20 gal of oil in Hyd tank to get it up to the full mark. I ran the machine in both directions for around 20 min. and lost 2" of level in the Hyd Tank. The machine travels well forward and backwards.

I can not find a dip stick on the rotary gear box. where should it be front or back? Could someone have taken it out because it was overflowing and plugged it off?

The oil drips down from the bottom side of the rotary swing gear area.

I have never run a excavator before. How should the rotary brake work and feel?

 

[LOFAYTX]

Is this how the Gear Box with Dip Stick and fill should look?

 

[lantraxco]

No, it looks like your machine only has check plugs:

 

[LOFAYTX]

Thanks for all the help, I did no know what was going on since I could not find a dipstick.

Since it looks like it leaks while the machine also just sits there I am going to check the swing motor first.

It looks like it might be possible to leak from Hud. tank thru motor case drain return.

 

[backhoe1]

you can see the dipstick in the picture you posted, that would be gear lube in there. if it's leaking hydraulic oil it is probably the rotary manifold. I went through this a few years back, machine worked fine, but leaked... It was the rotary manifold..

 

[LOFAYTX]

It leaks and drops a level in the Hyd. tank even when not running. I think this is Hyd. oil coming from the Hyd. tank returns line from the Hyd. case drain down to the rotary manifold or the swing motor.

Can I pull the swing motor loose and lift it up enough and run the swing to see if the swing motor seal is leaking?

 

[LOFAYTX]

backhoe1 my machine does not have a dipstick on the swing motor gear case unless it is attached to a hidden plug that needs to be pulled.

 

[backhoe1]

When I had a 690 that was leaking, I was told to look in inspection cover above swing gear, if it is full of oil and not just grease that would be swing motor seal. If the swing motor seal is leaking, the cavity would be full of gear oil. When my 200 had a bad swing motor seal, it filled the cavity up with gear oil and leaked around the outside of machine. My 690 had leaking rotary manifold and dripped hydraulic oil under machine. you should be able to smell the fluid and tell whether it is gear oil or hydraulic oil.

 

[LOFAYTX]

Since it leaks oil out of the Hydraulic tank when not running thru the return lines I am going to unhook the lines from the Hydraulic tank and fill them up and see which ones leak down.

 

[NW41]

On my 690E the swing motor gear case is lubricated with hydraulic oil. Since I've owned the machine I've had the gearbox out twice because the twelve 10mm Allen head bolts that attach the swing pinion to the bottom of the gear case have come loose or sheared due to excessive clearance between the gearbox and the machine deck.