I've posted earlier about my JD 310G stabilizer drift. I have all the test and repair manuals now and believe I have isolated the problem to the lockout valve. The only problem now is that according to the repair manual, the only repairable parts on the loader/stabilizer valve are the spool seals and not the lockout valve. I've called JD service and everyone who would know seems to be on vacation or unavailable. The valve from JD is over $3K. I've found used valves...other than seller integrity, is there any way to know that the valve I'm buying doesn't have the same problem. I haven't pulled the existing valve apart to check for scoring and/or don't even know if it is possible without damaging the part. Does anyone have experience with this or any comments regarding what they have found? I've attached the cutaway diagram of the suspect valve. I believe part numbers 11 and 13 are the problems.
If this is the same valve as you have, items 5 and 6 are what are noted as items 11 and 13 in the drawing that you posted. Those two items have different parts numbers, must be something different about the two parts, so i don't know that switching them with each other will work. Have you inquired if 5 and 6 are available? Also, it shows o-rings and backup rings on the body of those two parts, you could simply have a failed o-ring on one of them causing your problem. Hard to tell in the illustrations, but the two components look like a poppet style check valve. Remove #5 and #6 from your valve body and inspect the o-ring seals. If they're ok, remove the plug cap in the end of the poppet valve body. Inside you'll probably find a small spring that pushes the poppet into a seat in the valve body. You could just have a piece of debris lodged in the poppet causing your problem. Look closely at the seat and poppet for any scratches or signs of erosion that would allow fluid to pass through. If there is, you'll probably have to replace which ever one is bad, #5 or #6 that is.
TXGeoSolarPro, I read your earlier post about your stabilizer problem. Are you sure it isn't a leaking seal in the stabilizer cylinder ? Is it possible to switch the hoses on the valve body from the opposite stabilizer to see if that one bleeds off after the switch ? If it doe's then it is in fact the valve. I had the same problem and it was the cylinder seal.