On the OVS, what do you mean by "not functioning"? They can rust to the point of getting holes, at which point they need to be replaced. But if it's just plugged up you may be able to fix it with a good cleaning.
I usually spray some intake cleaner through it for a while and then fill it with degreaser and let it soak. A few iterations of this with a lot of sloshing and you might be able to free it up. Rinse it clean and blow the innards dry with compressed air before reinstalling.
i made my own ovs, it made a world off diff. smoother running.. i cut the old one aprt, nothing but rust and srapnel..just for kicks, i run clear vinel tubing from the ovs to the dipstick area..i can see that it works better..the old rubber tube, well ws crap.. with the clear vinel tube i can check the condtion of the ovs return oil , just by looking.