Question about plugging loader lines off. Massey 4345.

[Hersheyfarm]

No ideal why I called it a check valve..

You would have been post #2 if I could have figured out uploading a pic from my phone. For some reason my iphone does not like the desk top version of this site.

My initial thought was having an open line dumping into the sump would rob the hydraulic flow and that the remotes would act as the return. Then the talk of damage to the pump put me in panic mode. I put a gauge on after putting hose on and I’m actually getting 3200psi, not 2700. That’s if my tsc gauge is calibrated correct.

 

[Groo]

3200 psi is fairly high for a gear pump, but some can handle maybe 4000. Most tractors I've seen specs for call for less than 3000 psi. Most new implements I've seen use cylinders rated for 3000psi.
Might want to turn it down if you trust the gauge.