My son just bought a 94 ranger with 140k miles. It runs ok but he has no heat in the cab. Checking the coolant tonight and found it to look like chocolate milk! So a flush is definitely in order but that still doesn't explain the no heat issue. Both of the heater hoses going to the firewall are not warm at all and feel like they are empty?? What causes these hoses not to get hot? Also the t-stat was just changed.

Thanks!
Mark