there should be a pitcock on bottom of radiator to drain it. or take the bottom radiator hose with motor cold of course .
There is a drain plug just below the lower radiator hose.
left (ccw) to remove somtimes its very tight and break when old and brittle
Low coolant? Thermostat not opening? Radiator plugged or restricted? Cooling fan not working? Water pump not circulating coolant? System airbound? Hoses collapsing under pressure? Defective radiator cap?
You have to pull the lower radiator hose to drain/flush the radiator
There are 2 of them-one on each side of the radiator.
Check coolant level in radiator Check to see if it is "airbound" Remove heater hose to see if there is fluid running through it Bad thermostat
The coolant capacity of a radiator in a 1986 Chevy Cavalier is 10.3 quarts. You can use any standard radiator fluid that's made for all makes and models of cars.
The bolt to drain the coolant is on the water pump. The water pump is on the left side of the bike, just in front of the oil filter. Just remove the 10mm bolt CLOSEST TO THE OIL FILTER. You'll want to remove the radiator cap prior to doing this so the coolant drains freely. NOTE: Make sure the coolant is cold so you don't get scalded.
Look at the bottom or the rear side of radiator - or remove the lower hose
To replace the thermostat: 1. Use a suitable drain pan to drain some coolant out of the radiator so it doesn't cause a spill problem You will not need to completely drain the radiator. 2, Remove the water outlet. The water outlet is at the engine end of the upper radiator hose. 3. Remove the old thermostat, if present. Clean any gasket residue off of the thermostat housing and the water outlet. Install a new gasket and thermostat, reinstall the water outlet and fill the radiator with coolant. Check for leaks. Warm up the engine then when it is cooled off check to make sure the radiator is properly full.
Drain the radiator into a container. Remove the upper radiator hose from the engine at the thermostat. Remove the bolts, housing and the thermostat. Clean both surfaces and install the thermostat and gasket. Reinstall the housing and upper hose and top off the coolant.
Should be located in a removable housing at the engine end of the upper radiator hose Drain about 1 Gallon of coolant from the radiator REmove this housing Note how thermostat is installed Clean both surfaces Replace thermostat and gasket Re-fill coolant slowly to prevent an air lock Start engine and check for leaks Run engine to normal operating temperature with heater on Re-check coolant level