Massey Ferguson 180 loader lift

[Calgaryglenn]

Posting for my neighbor. 1969 MF 180 gas with Allied 600 loader. The unit was working, he shut down and now the loader will only raise very slowly an inch a minute. The 3 pt and power steering work as they should. We checked the oil and hyd filter and all seems OK.
Any ideas of where to start troubleshooting?
Thanks to all and protect yourself from the heat.

 

[Harry in Ky]

So what part of the tractor's hydraulics supply the loader valve? I would assume the tractor has an auxiliary hydraulic pump, a remote valve or two with steel lines leading out and back into the side cover where the PTO control lever is mounted? Yes/no? Might be hard to see in there what with all the platform and panels.