Starter needs a bit more coffee...
I think that the hose that you are referring to is to purge air from the cooling system of the engine. It is unique on the 1997 engines. It runs from the top of the coolant manifold on oil pump housing to the coolant reservoir. On later engines there is a fitting on top of the heat exchanger (oil cooler) to purge air.
Metal pipe location on the front of the engine:
The hose should be the one I referred to in this picture as "Coolant to oil cooler on top of the engine":
For parts, you may just need the hose listed here as (30) 99610620700, but possibly the others noted in the diagrams. I don't have a 1997 handy anymore to see the actual connections.
Possibly these, but I don't think the '97 uses this hose...
You should replace the oil dipstick tube while you are in there. It looks like yours was cracked and repaired.