Effects of using 100% coolant?

Well, if it's 100% coolant, I would think the car would run hotter. Anti-freeze is a poor conductor of heat, which is why you want/need a 50/50 mix. Water does a MUCH better job at carrying away heat.

I don't think this newly developed leak is a result of adding 100% coolant. Unless things got hot enough for them to expand...

-Tim

What's the total capacity of your cooling system? Was there still some diluted stuff in there to begin with? I can't remember exactly but I read somewhere that it's not good to use straight coolant because something to do with the heat transfer capacity of 100% coolant isn't as good as a diluted mix of coolant and water. In any event, it appears there is a problem and now you have to try and fix it. I'd recommend getting the cooling system filled 50/50 while you're at it!

Some loss of freeze and boil protection. Nothing to lose sleep about.

More likely it was losing the coolant before the addition, otherwise there would have been no need to add that much coolant.

Even in Nevada class low humidity and triple digit heat, have never needed as much as a quart of coolant/water mix.

You have a leak. That leak is potentially more dangerous to your vehicle than the modestly mismixed coolant. Get that leak found and fixed before you lose your engine.

If the hot light comes on, be sure you know how to deal with it using the heater, etc.

My experience with GM products of that era has been that there is always a few small leaks at or around hoses and various connection. So loss of coolant is not too surprising to me. I would do the following:

-Get 2 gals of pre-mix coolant (saw it at Wal-Mart for $3.50 or so) it's a Preston product

-Get a bottle of coolant sealer ($2 to $3 or so) and add to the radiator before filling with the above

-Place the heater control on HOT and Drain the system (on GM cars I think they still have the radiator drain valve) and dispose of the coolant in a safe manner. It kills birds and domestic animals if left on ground surface.

GM as well as most major automakers uses sealers at the factory to stop small leaks at various interfaces and connections.

|What are the possible effects of adding 1 gallon of undiluted coolant |to a car (wasn't overfilled)?

It won't hurt a thing. It doesn't conduct heat as well, and it would raise the freeze point. Both are very small differences. Unless your system is marginal to start with it is not a problem. I used to run straight antifreeze for years. I had heard that the local PD was doing that and it cured overheating. Probably no truth to that. What it did do was it allowed me to occasionally add straight water without worrying about excessive dilution. One thing to note is if you are using, or intend to use, stop leak, most of those products work best in a clean radiator with straight water. Adding stopleak to a pure glycol solution has a low chance of success. Ideally, you would drain and flush the radiator thoroughly. fill with water and stop leak (I like Car-Go or Bars Leaks brand, or K-W block seal if you follow the instructions EXACTLY). Drive the car and get it reasonably hot, let cool, then heat it up a 2nd time. Drain, refill with 50-50. thereafter top off (some periodic addition is normal) with straight antifreeze as needed. Rex in Fort Worth

There are a lot of opinions already but I'd like to add that even the antifreeze folks do not recomment using over 70% antifreeze (30% water). I have been told that pure antifreeze will gel when very cold. I know it pours like syrup when cold. Find and fix the leaks, then use 50/50 to 70/30 for best performance.

Hope this Helps - PoD

Why not just use the proper mix and add coolant in the proper mix if needed ?

|On Wed, 31 Dec 2003 15:38:33 GMT, snipped-for-privacy@REMOVEtxol.net (Rex B) |wrote: | |>I used to run straight antifreeze for years. What it |>did do was it allowed me to occasionally add straight water without worrying |>about excessive dilution. | |Why not just use the proper mix and add coolant in the proper mix if |needed ?

Until the last few years pre-mixed coolant was not readily available. Not everyone carries around a jug of 50-50 in the trunk. If you are away from home and need to add coolant, the easiest thing to do was to just buy a gallon of full-strength antifreeze.

Rex in Fort Worth

I'd like to add my experience with stop leak products. Most of the people here recommend flushing the coolant system with one of these products (and that probably is your best bet). However, some of them (read the directions for each) claim that they can be used without draining the system (just add it and drive around), and I had good luck with one of these. My 95 cougar was leaking a quart or so every few weeks (give or take), and after I added some stop leak that leak stopped completely (or at least I've noticed no leak in the past 4-5 months). I didn't even need to flush the system.

Anyway, if you care about your car I'd recommend the more thorough approach - however if your car is an aging POS like mine, and spending time and money on it isn't really worth it, you might just try adding some of this "on the fly" stop leak product. This was especially conveinient for me since I lived in an urban area, so flushing the system myself was impossible and shops around the area were crowded and expensive.

Regarding the effects of a mix vs 100% coolant and leaking - if you've got a temperature gauge and it behaves normally with your driving habits the solution you're using is probably fine. I doubt the mix affects the leaking. Flushing or adding fluid might affect it, but most likely you just didn't notice the leak, or a old small leak turned into a bigger one.

YMMV

Dave

There are exceptions to the general rule that more is better. And thats 100 coolant. It will not worked well as mixtures do and might even overheat the car. Its almost as bad as runing a car without a thermostat, thinking it will run cooler. for all quotes there is an equally opposite quote