If you add fluid to the radiator, make sure it’s water and antifreeze (coolant mix), because you can get away with a leaky head gasket for some time, but if the fluid that enters the combustion chamber is just water, you might only buy yourself 1/10th of the time, because water will corrode/rust things in mere days, where as the coolant mix won’t.
Coolant prevents rust/corrosion as well as cooling and preventing freezing.
You may have read, upthread, that I avoid this because coolant costs money and I am short on money right now. How much of this should I do? (According to the owner’s manual, the cooling system has a capacity of three gallons.)
The power steering lines on the Taurus ('93 model, at least) have nearly the most absurd routing I’ve ever seen. They connect to the pump, located at the front side of the engine, go back along the right fender, along the firewall, back up along the left fender to the steering rack. Making matters worse, they’re a mix of metal hardlines and rubber hose, so there are several places along their length that can start leaking.
They are almost impossible to see, let alone replace, unless you pull the engine or at least the heads. Plan B might be to train a toddler on how to use a wrench have trhem crawl in. 
Be that as it may, the drips on my driveway are almost directly beneath the tube that I pour the fluid into (and no, I can’t see the ground when looking through the intake).
Like I said… pure water, which you are slowly making your coolant, will destroy the engine internals in a short time: Week? Days? Coolant (50/50 mix of antifreeze and water) won’t corrode your engine. You might drive a crappy running engine for a long time with a head gasket leak and proper 50/50 mix: Months… year?
It’s up to you to figure out how much the antifreeze costs, but seems to me antifreeze is much cheaper and better than a destroyed engine you can’t even start/drive.
Of course, if it gets into the 20’s (F), then an all-water coolant will end your engine’s life in one night. The block will freeze/crack and your engine will be kaput.
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I have lived in Southern California for over 60 years. We have never had freezing weather here.
I’m skeptical about this part. Sure, running straight water is going to eventually lead to corrosion in the cooling system (which is reason enough not to do it) but with a head gasket leak it only leaks into the cylinder when the engine is running. When the engine is running, it’s a bazillion degrees in there so the coolant that leaks in will flash to steam pretty much instantly and go out the tailpipe along with all the other water that’s a byproduct of the combustion process.
And, really, if you’re getting large amounts of coolant into the cylinders and somehow into the engine internals, you’re screwed either way. The bigger issue is that the coolant will contaminate the oil, which anti-freeze isn’t going to do much to help with.
A friend checked out the system today; followed the lines; found a big leak about at the bottom of the engine mass, just back of the radiator, kind of in the middle. I don’t know what part of the system is at that point.
how so? if the gasket has failed between the cylinder and a water passage, the residual pressure in the cooling system can push water into the cylinder after you shut the engine off. In severe cases, this can result in hydrostatic lock the next time you try to start the engine.
not something we can diagnose on the internet. Sorry, but that’s the way it is.
The friend located the leak in the power steering system in a line running just behind the radiator. Color me suspicious, but I wonder whether the mechanics who replaced the radiator might have danged the fluid line in the process.
That should read “damaged.”:o
The friend tested the system with colored fluid. He found the exact point where the line was leaking: in a line close to the fluid intake port, at a sort of knurled connection between the metal line (running from the steering mechanism) and a plastic tube connected at the base of the intake port. I saw it myself: he added the fluid, and had me start the engine then turn the steering wheel to one side. Then I came out to the front of the car and saw the fluid leaking out of that point in the line.
…and he replaced a connection that was leaking badly, so that the car was driveable.
Maybe a drop or two will sneak past after the engine is shut off (and immediately flash to steam in the still hot cylinders) but there’s not going to be coolant actually accumulating in the cylinders on anything but a head gasket leak that’s so severe that the car is no longer drivable. Which does not seem to be the case here. Yet.