Volks,
Just had radiator rodded-out and repaired on 82 Diesel Westy. Both upper
and lower radiator hoses looked 15 yr old flimsy so I decided to replace
both. Incidentally, this set up is similar to gas engines and the
radiator identical. Get this:

Hose    Dealer Price
Upper   $35.75 (3 or 4 inches long!)
Lower   $77.20
Total   $102.95
I instead went down to my local Hardware store that stocks "heater"
hose. I purchased 4 feet of the most bullet proof coolant system hose I
have run upon, it is at least 2x thicker than the the original hoses.
Best part: $12.00. Cut to fit! It fits like it was designed to be there.
The size is 1.25" (inch & a quarter), and should be available at a
hardware store, and certainly at any marine supply store.
Mark Magee
87GL
82 Diesel Westy
Kemah TX USA