Longhunter7, in my previous post, "primitive" refers to the control system, which consist of one thermostat and nothing else.
As far as the coolant, here is a summary of points:
1) Change coolant at least every two years. The coolant has many duties and the effectiveness of the coolant diminishes in time even if the vehicle isn't driven.
2) Get coolant test strips to check for acidity and freeze protection. "Cooltrak" is available on line (Google it) and you get a plastic jar with test strips. Just dip into coolant and compare the color change to reference chart.
3) Use an antifreeze with low silicate formula. I use 4 gallons Texaco"Heavy Duty" antifreeze, 3-1/2 gallons of distilled water and 2 pints of SCA (Supplimental Coolant Additive).
The purpose of the SCA is to prevent scale formation and "foaming".
4) I would highly recommend that you install a coolant filter. It doesn't take long and helps remove gritty substances, like rust and core sand from the coolant, which shortens the life of the pump and seals.
When changing coolant it may hard or impossible to remove drain plugs on the engine block, so I use the following procedure:
1) Drain the radiator. It removes about 5 gallons from the system.
2) Refill the radiator with water (distilled is always best).
3) Start and run the engine until the thermostat opens, which should be at about 180 F. You will need to cover the radiator with the winter front or a piece of cardboard.
Run engine for 5-10 more minutes.
4) Let cool off and drain radiator again of 5 gallons and refill with 5 more gallons of water.
Repeat this 4 more times at which time only a small percentage of the original coolant is left.
5) Finally, use 4 gallons of antifreeze plus 3-1/2 gallons of water and the 2 pints of SCA. Run engine at 180 or above for a final mix.
6) Test coolant with test strip.
You will see an article on this in next? issue of MVM for more details and pictures, meanwhile I'm here 24-7 if you have any questions.
One point that I'm trying to make is that the dash mounted temperature gauge will not tell you much about the cooling system, it requires constant checking for leaks, condition of hoses etc. and the coolant itself should be clear. Make sure the radiator cap is in good condition too.
I'm sure much was left out here, but it's a beginning.