Spool Valves

[Tx Jim]

I'm not trying to be argumentative but trying to keep info correct. Feel free to correct my mistakes which unfortunately I sometimes make!!!!!!!!! I've never seen the chart you listed. I suppose chart came from JD website from it's address? That chart listed 3020 @ 14 GPM & 4020 @ 18 GPM. That chart had my 4255 listed correctly @ 26.5 GPM. Very few JD's farm tractors built from '61-'93 were open center especially if one doesn't include the ones built by Yanmar. Open center hyd models that come to mind are 1010,2010 & 3 cyl model 820,830,early 2040's. After '93 my knowledge dims without my researching. I've already contacted Peter @ Tractordata so we'll see what he thinks.

 

[Tx Jim]

Peter at Tractordata emailed me back and stated 3020 build sheet shows 20 GPM but doesn't state if it's the early or late model.

 

[Tx Jim]

J-J
Could you please advise me where you located this chart you posted?
Thanks,Jimhttps://jdparts.deere.com/partsmkt/document/english/pmac/9736_fb_HydraulicPumpSelectionGuide.htm#_JOHN_DEERE

 

[J_J]

Jim,

Did you say this? It will surprise me if a 3020 has 18 CPM hyd flow

Anyway, I think the list came from Yesterdays Tractor.

 

[Tx Jim]

Jim,

Did you say this? It will surprise me if a 3020 has 18 CPM hyd flow

Anyway, I think the list came from Yesterdays Tractor.

Yes I stated that it would surprise me if 3020 has 18 GPM after reading on Tractordata that it's larger brother(4020) only had 13 GPM. I don't have a JD 3020 or 4020 technical manual to verify and I left JD dealership in 1987. I'm an avid member of Yesterday's tractors discussion forum but I've never seen that chart.Thanks for your reply,Jim