John Deere 410d backhoe

[cosmo49]

I recently purchased an older JD 410 d backhoe. The hydraulics were slow so I assumed the pump was weak and replaced it. It made no difference. I have a manual and it suggests a problem in the priority valve. But the manual I have is apparently for a later model tractor that doesn't look anything like mine so I'm not sure where the priority valve is. My tractor sn is 371665T. Suggestions?

 

[Leejohn]

The 1st thing I would do is to check the max psi of the pump to see what the relief valve is set at. For that you well have to have a gauge to set it. I think a priority valve is for flow not psi, that would slow it down but not change the power. If the psi is there and slow speed then yes go for the priority valve.

 

[Tx Jim]

As a former JD dealer service manager it never ceases to amaze me the number of hyd pumps that get replaced without having performed proper diagnostics to determine that replaced pump wasn't the problem. Below is a parts schematic for priority valve for your tractors serial number range. My knowledge of ind tractors is limited as I was employed by an "ag only" dealer BUT priority valve on ag tractors gave steering priority but unless stuck shut won't affect stand-by pressure. I think the 1st thing you need to do is check stand-by pressure which according to Tractordata.com should be 2755 psi. How long since hyd filters were changed?