Coolant system questions

[Mr 5 0]

Flushing methods vary but generally, on a cool engine, open the overflow tank cap and remove the radiator cap. Open the heater valve (on the dash) and turn it to full hot. Find the petcock on the base of the radiator (passenger side ), open it (carefully) and drain the coolant into a big pan.

Run water through the radiator one or two times, then close the petcock, fill the radiator with water again and run the engine until it's warm (thermostat opens) shut it off, drain it again. You should do this until the radiator flows mostly water. It's called the dilution process and works fine - if you're patient.

Refill with a 30/70 coolant (anti-freeze)/water mix for best cooling. Add the Water Wetter (1 bottle is fine). Close the heater valve and run the engine without the cap, heater closed, looking for air bubbles. This can take awhile.

Sometimes, jacking up the front of the car while adding the coolant/water mix can helps eliminate air being trapped in the system.

Be sure to check and replace the radiator cap if the rubber seal looks cracked and close the petcock and overflow cap, before adding the new coolant.

Make certain the thermostat is installed correctly (pointed end toward you). Use Ultra Blue or Permatex Avaiation sealer on the thermostst housing and don't overtighten the housing bolts. A 180 thermostat is O.K. but the stock 'stat works well and I recommend it.

Keep a close check on the system for leaks, especially around the thermostat housing and watch the temperature gauge for high temps, indicating air still trapped in the system.

Dispose of the old coolant at a Jiffy Lube-type garage or down the kitchen sink (this is legal in most localities) but do not pour it into a storm sewer or 'in the woods'. Be responsible.

There are other variations on this method but this is basically what I do, every 30,000 miles or so. This is also a good time to do a careful check of the hoses, especially the heater hoses and replace if necessary. They're vulnerable and replacing them, if necessary, is cheap protection against being stranded and/or cooking the engine.