642 Chaincase Over full?

The last time I checked the chaincase level on my 642, even though it was on level ground, it appeared to be over filled. The oil came out with good head pressure. I do have a leak somewhere in the system, however it seems to leak when sitting. I am wondering if a leaking o-ring on the wheel motors might be the main cause for this. In the near future, I need to pressure wash the machine and check to see where the oil is comming from. If this is happening, if the chain case fills up, where is the most prevelent area for it to leak out at? Keep in mind the chain case and the hydro system both run the same oil-10W-40.
Thanks
Bernie
Any Ideas?

If you are loosing oil from your tank and your chain case is over full i would agree that you may have a leaking O ring on a drive motor. The good thing is they are reasonably easy to replace.
Now if this is the cause of the oil leak you talk of, there is a breather under the arm that activates your lift function. It could also be coming from the inspection covers on the chain case, they never seem to give a perfect seal and oil can leak out. On level ground remove the front plug till the oil stops, this is the correct level.

Tazza said:

If you are loosing oil from your tank and your chain case is over full i would agree that you may have a leaking O ring on a drive motor. The good thing is they are reasonably easy to replace.
Now if this is the cause of the oil leak you talk of, there is a breather under the arm that activates your lift function. It could also be coming from the inspection covers on the chain case, they never seem to give a perfect seal and oil can leak out. On level ground remove the front plug till the oil stops, this is the correct level.

Click to expand...

What I would do to troubleshot from what you have said , I'd pressure wash under the cab if possible , level ground pull plug and drain oil down to level of bottom thread of plug , fill the hydraulc tank and operate machine then check the levels come up and going down----------

Fishfiles said:

What I would do to troubleshot from what you have said , I'd pressure wash under the cab if possible , level ground pull plug and drain oil down to level of bottom thread of plug , fill the hydraulc tank and operate machine then check the levels come up and going down----------

Click to expand...

Thanks for the advice. Yes, the oil tank is loosing level, but probably only a quart or so every 6-8 hours of operation.

Tazza----When I checked the level of the chain case originally, I pulled the plug and stuck it back immediately because I was sure I did not have a big enough pan under the machine considering how much head pressure the oil came out with. I will pull the plug after I get a good size pan under the machine. I am assuming this could hold gallons more oil than then it is supposed to. Anyway, where is this breather you talk about.....the only breather I am aware of is on the oil resevoir fill cap.

Bernie

bfingar said:

Thanks for the advice. Yes, the oil tank is loosing level, but probably only a quart or so every 6-8 hours of operation.

Tazza----When I checked the level of the chain case originally, I pulled the plug and stuck it back immediately because I was sure I did not have a big enough pan under the machine considering how much head pressure the oil came out with. I will pull the plug after I get a good size pan under the machine. I am assuming this could hold gallons more oil than then it is supposed to. Anyway, where is this breather you talk about.....the only breather I am aware of is on the oil resevoir fill cap.

Bernie

Click to expand...

The way i have done it in the past was to have a pan under there and remove the plug, let it fill then put the plug back in, empty the pan then repeat. Whatever way you are happy with though. If its FULL you will have approx 25 litres extra in there, the tank holds about 25-30 to be at the rite level, so double that for FULL.
The breather is like a bronze screen thats under the bar that runs across the chain case that links to the lift pedal, you won't be able to see it unless you remove this bar, its also under the hydro pumps so you can't get to it. Its not something you will need to service anyway. I think there is another one under your park brake, but not all models have this.
I hope that helps you a little bit.