I have a 99 763 high flow G series - I left the machine outside in the cold for 2 days- when I started it in the morning I let it idle and warm up before moving it, after moving it I found a puddle of hydraulic oil under the machine- after bringing into a heated garage I lifted the cab to see where the leak was coming from- it was leaking out of the back side of the hydraulic control valve, after further checking I removed a green plastic cover over an aluminum plate with a pin hole in the center of it. I tracked it down I think it is a spool valve seal- I am hoping it is just a bad seal, there are 2 green covers on the back of the control valve- but only the top aluminum cover has a pin hole in the center. My questions are- can this seal be changed in the machine are they hard to do or do I have to pull the control valve out and do it on a bench and do these seals ever go bad with no warning, I did not have a oil leak till I left the machine out side in the cold (temp was between 0 and 28 degrees)- the machine has only 1365 hours on it. Any help or advice would be greatly appreciated . Thanks Chris
Most definitely leaking control valve spool seals, common Bobcat problem. As to whether you can do the repair with valve installed or not, I don't know, haven't done an AHC machine yet. The trick would be driving the connector pin out with a drift pin. It might be possible if you remove the panel that the drive levers are mounted on, this opens things up quite a bit, and may have to remove the manual boom descent valve to gain good access to the actuators. I don't have any pics of a 763G AHC, but I do have some for the 773G AHC, they should be similar. Once you remove necessary components to gain access to the front of control valve, remove the two allen head screws (items 3) that secures the actuator retainers. Pull the actuator away from control valve slightly, then drive the spool connector pin out with a proper drift pin. You can now remove the actuator components from the control valve, remove upper actuator in same manner. Once you get this far along, there's info in this thread that will help you with the rest of the procedure. > HeavyEquipmentForums
Thank you willie59, that post was very helpful, I will be ordering the seals today and I will change the seals this weekend. I bought this machine used and have had it for 3 years with no problems, until 2 days after the last payment. I will let you know how it goes. Thanks ...Chris
Hi willie59, I changed the seals this past weekend, I was able to do it in the machine once I removed the control panel- the info you sent was very helpful. Its all together and no leaks. This forum and its members are great!! Thanks again Chris
Good news indeed Chris. :drinkup