Thanks fo your info/insight.

This has been discussed before, and I even went and spoke with our local JD foreman about it. JD foreman says that what they have seen, in the past, is that when they return the power beyond oil, back to the PB block, then sometimes, they get some surging at the vacuum motor. Not always. They have tended to put these "old style two line/hose motors" into case drain, for the return. {You bring up the point about hyd pumps and different models/series(20,30,40); So that makes me wonder if the JD foreman has kinda "grouped" all these tractors together and maybe has forgotten some of those differences}


JD foreman did say that it would work, either way/method. He was just telling me his experiences.



Sidenote: When Dad purchased used planter(from dealer 45 miles away) they had it hooked up, to return into PB block. THEN, during a service call, from local dealer(20 miles away) they noticed the hook-ups; and that field service guy said it was wrong. They put it to the case drain area.  


I wasn't around when all this happened(out of state) and never got a good description of any reasoning of one verses the other. This planter only need 8-8.5 inches of vacuum, so I don't believe that it uses as much oil volume, as a planter setup with E-sets. Haven't noticed any excessive oil heating.



Maybe, this year, I should try returning the oil to the PB block and see what happens.(I know what Dad, will say: "Leave it alone! It is worked perfectly fine, for all these previous years.")