Thanks Ken for the info, next week I will have to spend a day studying that 853 and the books so I know more about it. It seems to me that in one of your past posts you mentioned running a Serco loader which is coincidental because I just retired as a machinist from Serco. 41 years machining , 22 at Serco the last 10 on CNC. I have been reading the thread from Sterclan on the groany 630, my 632 I got last fall groans a lot on turns, less with high rpm tho. When I got it I changed the hydraulic filter and found it was collapsed inside, bobcat brand too. I then changed the bronze filter and found not much of the brassy particles but dirt and very fine wire bits which I hope were part of the filter. Is it the nature of these old ones to groan since they are driven directly from the motor to the chain or are there problems I should be looking at. The machine is just used around home a few hours a week. One thing tho when I am coming off the trailer with fairly steep ramps it does not gain speed on its own which I think it would if there were much wear in the drive motors. jerry
They all moan and groan some, especially when pushing hard or if rpm is low. That pretty normal for any skid I have ever sat in. (bobcat, deere, new holland) However groaning gets worse if you have problems, so its tough to call it based on that alone.
When you say the filter colapsed , I'm wondering if the bypass is disabled and the pressure differential crushed the element??
Most of the time one side just gets lazy as the oil warms up if the motor is bad. Yours sounds more like a charge issue, or could just be a sender. You need to ge the pressure guage out to verify this. Perhaps change the filter and open the old one and see if there is any new trash.
We have had our old serco (around 86 vintage, model 200, 3208 Cat. for 8 years now.
We bought it as a fixer upper (at 7600 hours, motor was smoking some, needed injectors, center boom knuckle was worn bad, and the 1/2 serco bypass clam was busted though the cross member of the jaw on the prong side, lots of new steel and welding) and have used it 1000 to 1500 hours for loading tree lenght and slash and load 100”. Its a good basic design that is easy to service and repair and rugged as hell. Those twin 6” main lifts just won't give up.
It has handled 15000 or so cords for us now will vary little trouble. However I need to pull the center manifold out and re seal it now. It leaks when it feel like it while the unit is sitting and loose all its hyd oil. Thats a job I'm not looking forward to.