Coolant system questions

[mustangLX92]

What is the proper way to drain and flush my coolant system? I was planning on using a 50/50 water/coolant mixture, 180 t-stat, and 1 bottle of water wetter. Does this sound ok?
Thanks

[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.

[mustangLX92]

Thanks for the info Mr. 50. How do I measure the 30/70 coolant mixture?

[Mr 5 0]

You guess.

The system takes 14 quarts but you won't see that without removing the freeze plugs so when you add new coolant, mix it in a 30/70 measure by doing what I do.

I take an empty gallon jug that held distilled or 'bottled' water and mix the coolant/water in there. Just fill a third of the jug with anti-freeze, then fill with water. Distilled water if you're a fanatic (ahem). Shake it up a bit to mix it. Then pour the mix in the radiator, slowly. Do that until the radiator is full. I wait until all the air is out and I'm sure I have no leaks then I add the (expensive) Water Wetter. Works for me.

[95mustanggt]

30/70 provides good cooling capacity, but if it gets cold were you are, you may want to go 50/50 or even 40/60.

In Canada, using 30/70 will put you in big trouble!

Then again, if it doesn't get cold, 30/70 is fine.

[90'5.0 Conv]

What if it's hot as H*** where you live? Should you go 20/80? It's already in the 90's here in S. Georgia.

James

[Mr 5 0]

James:

A 20/80 mix is feasible.

The anti-freeze ('coolant') retards corrosion and you want some in the system. 30% is good but 20% will cut it. That would be my bare minimum mix for a daily driver.

Different mixes for different climates and seasons.

Obviously, some bitterly cold climates like Canada should probably go to a 50/50 mix when cold weather is imminent. A 30% mix in the warm weather (all 3 weeks of it) still works, but you have to perform two drain and refill's per year.

Water cools better than anti-freeze. Use more water in hot climates. Anti-freeze doesn't cool as well but it protects against system freezing in cold climates. Use more anti-freeze when it's very cold.

Just use common sense.

[gtsr515]

Mr. 5 0, here in south central Florida it gets as about as hot as you can imagine, street temps over 140 degrees, what would you recommend for that condition......bone stock 1993 bone stock cooling system, never a problem yet, but wondering...

[Mr 5 0]

gtsr515:

I recommend you drain and flush the cooling system, add a 30/70 coolant mix and a bottle of Water Wetter. Make sure your clutch fan is working properly and replace the radiator cap if it's over three years old.

The stock radiator is marginal. If you develop any kind of cooling problem that isn't due to a failing clutch fan or other component, upgrade to a 3 row radiator, as I did. Works great.

Water Wetter is also a must-have for any cooling system but especially an older one driven in extra-hot climates. It's not a panacea but it certainly helps. Reduces temps about 10 degrees.

If you can't find it locally, order it by mail. Worth the trouble.

[95mustanggt]

Originally posted by Mr 5 0
James:
Obviously, some bitterly cold climates like Canada should probably go to a 50/50 mix when cold weather is imminent. A 30% mix in the warm weather (all 3 weeks of it) still works, but you have to perform two drain and refill's per year.

Was that a shot at my country's summer?

I'm really going to miss Texas weather