Drain the radiator first then remove the hose connector from the hose you want to replace. Once loose try pushing on the hose with a twisting motion firts to help release its hold on the pipe its connected to. If it is really stuck you can stick a screw driver under it. Just be careful not to hurt the metal connection.
Now take a scotch pad and clean the connection off really good. Cut to fit the new hose and test fit it in place. Then tighten down the connections. If you had the original style clap style connectors I suggest you replace them with new hose clap style connectors. They original ones live in the heat and they can fail to hold now that they are old and heat tempered.
Refill the radiator with regular water and run the engine to temperature for about 10 minutes. Check for leaks and if none are present then drain it again and refill with a good anti freeze.
Where is the fuse for the cooling and heating air conditioning system on a Toyota prevla 1994?Read more: Where_is_the_fuse_for_the_cooling_and_heating_air_conditioning_system_on_a_Toyota_previa_1994
By using water
8.9 Quarts for a 1980 Toyota Pickup with a 20R.
Replace the thermostat and service the cooling system.
Replace your thermostat whenever you replace the coolant and service the cooling system. Also replace it if you suspect it is sticking.
It's not easy
When you service the cooling system.
Check around for prices. I had to replace my entire cooling system last year, and it was $1,900 including labor. My point - you shouldn't have to pay that much, but it can be hundreds of dollars.
look in how to bleed air off cooling system
Usually if it's not serious, check the cooling system hoses.
Drain the cooling system. Remove the water hoses from the heater core. Remove the heater core retaining bolts. Reverse the process to install the new heater core.
It's probably not a good idea. The "permanent" antifreeze has different characteristics and is designed to help the cooling system perform better and last longer.