Hello all, long time lurker here with questions. We have an old cat 235 on the farm pulling stumps. We lost an ''O'' ring the other day under the house and after she puked out a bunch of oil now we have almost no swing, the track breaks come on when we dont want them. In general, it's not playing nice at all. My book says its air in the pilot controls. Anybody have words of wisdom ? Thank-you ! Dave
If it is full of oil again, check your book for bleeder valve locations on the pumps and get the air out of them. Cavitation will ruin them in short order. Once the air is out, generally full movement of all functions will purge the cylinders and motors and things will smooth out. Some machines are a real pain, some have express bleeding procedures, etc. Usually in the field the above will suffice. Just make sure to bleed the pumps, unless they have an auto bleed system in place, not sure on the 235.
I have a 225 and it has a bleeder screw on the end of the control valves, looks like a brake bleeder screw. Track down the hoses to see what valve they go to.
If you fixed the leak and filled the hyd oil it should work. Now since you say it has poor hyd performance and the brakes will not release I would say tho check and correct cause of low pilot pressure. It should be 345 Psi measured at the large 1 1/2" hex JIC cap under the cab with warm oil at low idle. Later Bob
I'm agreeing with the low pilot pressure. I've seen lots of these machine run out of oil before that are just topped up and ready to go. No bleeding required. When you say leak under house I'm wondering if it was on the pilot valve. It could be that something got contaminated or a piece of o ring got in the valve. When you lift the safety handle in the cab make sure the pilot on off spool under the cab is moving properly.