Thanks again to everyone who replied to my posting earlier this week. These are somewhat different topics, so I'm starting a new thread. I checked the Brickboard FAQs, but didn't find answers to these questions.

I own a 1980 242DL (NA) and a 1989 Toyota Camry and have just serviced the entire cooling system on both. Thanks to the FAQs and contributions from the last postings, I modified how I'm storing my 242DL. In yesterday's mail, I received a Wahler thermostat for the DL and a Stant for the Camry; both are considered top-of-the-line/OEM quality.

As to storage of the DL, I bought Sta-Bil Fogging Oil and sprayed generous amounts down each spark plug hole, into the top of the intake, and into the oil cap on the cylinder head. To disperse/distribute the fogging oil down the cylinder walls, I then cranked the engine, admitted I was a little lazy, so I turned the ignition key with the ignition coil unplugged from the wire, instead of hand rotating the crankshaft). Based upon another website, I plugged the air intake manifold hose to reduce moist air from entering the combustion chamber (though I don't think that applies to fuel injection systems like the Bosch CIS on my DL). I live in a humid/moist/foggy area where everything unprotected seems to rust within a month.

Question 1: how often should I crank the engine and add more fogging oil?

I bought the long-life Peak brand antifreeze and put a 50/50 mixture into my cooling system. After doing that, I found out there's a lifetime version of Peak, which has almost the same ingredients, per Peak's website:

Peak Global Lifetime: 90-97% ethylene glycol, 30-50 ppm denatonium benzoate, < 5% diethylene glycol, < 5% hydrated inorganic acid and organic acid salts (proprietary), < 4% water

Peak Long Life: 5 years/150k miles, phosphate and silicate-free
90-97% ethylene glycol, 30-50 ppm denatonium benzoate, < 5% diethylene glycol, <5% organic acid salts (proprietary), < 4% water

The difference between these two is only the inorganic acid salts.

Peak Conventional (2 year) Green Concentrate:
90-95% ethylene glycol, 0-5% diethylene glycol, 1-2% dipotassium phosphate, 30-50 ppm denatonium benzoate

The difference between these is the inorganic and organic salts and dipotassium phosphate

Wikipedia discusses coolant and says: “In the absence of leaks, antifreeze chemicals such as ethylene glycol or propylene glycol may retain their basic properties indefinitely. By contrast, corrosion inhibitors are gradually used up, and must be replenished from time to time.” The word "may" is troublesome and wikipedia implied shelf-life and didn't address specifically a car in storage.

Question 2: what is the lifespan of the 5 year coolant in a stored engine that is NOT started, and how often should I change it?

Questions 3 and 4: Assuming the car is stored for more than 5 years and not driven or started, instead of changing coolant, can I safely add corrosion inhibitors at 5 years (or whatever interval is proper)? If so, any recommendations as to brand/chemicals or how I can get the underlying chemicals cheaply, say from a chemistry supplier?

My Wahler thermostat box has a date of 1997, implying that it was manufactured 17 years ago. I bought it from a store in Southern California (Ontario, specifically). I will keep the Calorstat thermostat as a back up. Thermostats installed in cars have the benefit of corrosion protection from the antifreeze. That benefit does not apply to thermostats stored in a garage in a humid environment. Should I coat the non-installed thermostat in oil, or some other chemical to protect it from rust? Same question as to the thermostat gasket.

Thanks!