My L3750 hydraulic system, over a few months, slowly stopped the front end loader lifting, and finally the forward movement of the tractor. Lowest gear barely got it in the barn. Draining the fluid and cleaning out the return hole on the filter, there was almost a 1/8 cup of flaky crud. It is all thin flakes, about the thickness of two or three sheets of paper, and sizes from bits to some the size of a fingernail. Several times I poured oil in the trans, and drained move stuff out until no more flakes appeared, replaced the oil, new filter, and mowed a couple of acres; lifts fore and aft seem to be working fine. My question is where is all this coming from. This tractor spent a lot of years in calif, and colo. Is it possible that sitting for years, in hot dry climate, the oil could have formed a "varnish" on the inside of the trans.? The material is too flat and a bit shiny on the flat pieces, and consistent in thickness, to have come from the clutch or brake lining I think. Any suggestions other than continuing to drain and change filter when the crud stops everything from working?
hydraulic system flacky crud
- Thread starter wwc
- Start date
Drain -n- change should eventually resolve the crud.... but can get VERY expensive if using Kubota SUDT2 fluid for every change.
Perhaps when you drain it, pull off the lower end of as many hoses as you can to drain them too. Then refill with el-cheepo fluid (tractor supply?) I would expect the filter(s) and screen(s) to catch most of the debris.
Heck... if you are just trying to wash out the crud... even the cheepest motor-oil would suffice.
For final fill, use the Kubota SUDT2 fluid which is less likely to leave behind 'varnish' (and may even dissolve it.) Synthetic fluids are known to be good at cleaning up the residue left behind by dinosaur-based fluids.
Perhaps when you drain it, pull off the lower end of as many hoses as you can to drain them too. Then refill with el-cheepo fluid (tractor supply?) I would expect the filter(s) and screen(s) to catch most of the debris.
Heck... if you are just trying to wash out the crud... even the cheepest motor-oil would suffice.
For final fill, use the Kubota SUDT2 fluid which is less likely to leave behind 'varnish' (and may even dissolve it.) Synthetic fluids are known to be good at cleaning up the residue left behind by dinosaur-based fluids.
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I think what you a finding is brake lining not crud. If you keep running at some point you will have metal to metal then you have a mess. Have a closer look at the material you removed.
I have strained the hydr. oil thru some material I get from a local diaper manu. I have not seen any metal residue or anything else but the flakes which do not have the rough surface of brake linings or clutchs. I did pull off some hose but they did not have the crud in them. Thanks for the answer. I ll be looking for anyone who may have had a hard crust form in the trans case.