963 Dumping Hydraulic oil to chain case

   / 963 Dumping Hydraulic oil to chain case #1  

glennkangiser

New member
Joined
Jul 30, 2010
Messages
7
Location
Mariposa, CA
Tractor
Bobcat 963
I have been playing with this for a bit - still trying to figure out the real problem.

We pulled both drive motors - replaced the seals and still have the problem though it doesn't seem as bad.

Oil is draining into the chain case overnight it seems. The back cover plate was leaking so we pulled it and resealed it -

I was having trouble locating the leak as I would try it then find nothing as it went out the back cover plate on tipping back.

Filled the hyd tank. Fine when watching it. Working, I lose about 2 gallons an hour.

The only other place where hydraulic fluid can enter the chain case is the hydraulic disk brakes release if I am thinking right.

I pressure tested the brake system through the release hose with a gauge on a Portapower, and did not find a leak at pressure ranging from 500 to 2500 - possibly at low or no pressure? Just thinking that worn seals may seat with pressure but leak released under low to nearly no pressure.
 
   / 963 Dumping Hydraulic oil to chain case #2  
I am experencing the same problem with a unit i reciently purchased and am in the process of investigating . It does seem that hyd fluid is being lost when unit is not in use after setting for nearly a week I lost nesarly 5 gallons of fluid.
All information on the subject would be appreciated and i will pass along info as i recieve it.
 
   / 963 Dumping Hydraulic oil to chain case
  • Thread Starter
#3  
My buddy had an 853? and they replaced the motor seals and also some seals going into the final reduction. The motor seals did not stop it by themselves.. they found out that the Bobcat mechanic had left them out.

I think that is because all models do not necessarily use the seals into the reduction case - some do - some don't - maybe even on the same machine.

Mine only has the motor seal and an O ring around the motor flange - mo seal into the case. The new seals I put in the motor slowed it down but did not stop it.

I made a filter for my hand pump and am currently pulling the oil from the chain case and filtering it the recycling it.

I think the only other hydraulics in my chain case besides the motors is the hydraulic disc brakes. They hold at higher pressures but may be leaking when sitting under only tank pressure - more testing needed I guess. I don't have time or money for a lot more trouble shooting right now.

Mine also loses fluid overnight.
 

Tractor & Equipment Auctions

2008 Toyota Tacoma 4x4 Pickup Truck, VIN # 5TEUU42N18Z513386 (A51572)
2008 Toyota Tacoma...
2021 Chevrolet Silverado 5500HD Service Truck, VIN # 1HTKHPVKXMH043579 (A51572)
2021 Chevrolet...
UNUSED RAYTREE RMPP680 HYD POST POUNDER (A51248)
UNUSED RAYTREE...
2024 Bintelli ActivEV Pulse Electric Golf Cart (A51694)
2024 Bintelli...
UNUSED CHERY INDUSTRIAL 14' BI-PARTING IRON GATE (A51248)
UNUSED CHERY...
BBQ Longhorn Bull Smoker (A51572)
BBQ Longhorn Bull...
 
Top