Coolant rust?

[c96drumm]

And only use the tap water to flush, don't leave it in the system. Distilled water is the only water that should ever be allowed to stay.

This ^ ^ ^

I've been using Prestone diluted with distilled water for many years and miles. No rust or mineral deposits.

 

[CDW6212R]

When you get it flushed out well enough, then add some Water Weter into the final coolant. That increases the heat transfer of the coolant, which will make a very slight reduction on temps on the gauge. Antifreeze does not transfer heat as well as any water etc, use as little as needed for the climate.

I see zero degree lows in Winter here, so I can run about 30% antifreeze and be safe. That saves money and the coolant works better than at 50%.

 

[joney]

When you get it flushed out well enough, then add some Water Weter into the final coolant. That increases the heat transfer of the coolant, which will make a very slight reduction on temps on the gauge. Antifreeze does not transfer heat as well as any water etc, use as little as needed for the climate.

I see zero degree lows in Winter here, so I can run about 30% antifreeze and be safe. That saves money and the coolant works better than at 50%.

Water Weter - nice idea. It does get down to -40 here, not every winter, but have to go with that mix. How often do you change or flush your coolant? Didn't know TN got that cold either.

 

[C420sailor]

I do mine every 60k I think? Gotta check. Whatever the book says.

 

[CDW6212R]

Water Weter - nice idea. It does get down to -40 here, not every winter, but have to go with that mix. How often do you change or flush your coolant? Didn't know TN got that cold either.

Yes for -40 you should go with 50%, but buy the concentrate always, it's cheaper overall. The Water Weter also lubricates the WP seals, which I used to buy an extra product for. Those were about $5, and the Water Weter is about $10 now.

Five years is a good limit to set for coolant, less if something goes wrong and the system is worked on for something. Keeping regular water out is a big thing to have the coolant last a full term; use distilled, grocery stores have it for about a dollar.

 

[joney]

Quick question/update: I checked the actual radiator, Coolant is orange and no flakes, quite clear. BUT: it's only good to -20 and there's a very cold snap coming BEFORE my appointment to get it flushed. Can I top it off with the green coolant I have on hand for a week or so? (I don't think the orange coolant was for the 2nd gens, correct me if I'm wrong..). Got to do this today or tomorrow. Also, puzzled why the reservoir look so dirty but the coolant fluid IN the radiator looks fine)

 

[donalds]

why the reservoir look so dirty but the coolant fluid IN the radiator looks fine)

Normal amount of rust
Now you have a idea what it needs to look like

 

[donalds]

I use prestone universal .....yellow

Try not to mix them

 

[CDW6212R]

Quick question/update: I checked the actual radiator, Coolant is orange and no flakes, quite clear. BUT: it's only good to -20 and there's a very cold snap coming BEFORE my appointment to get it flushed. Can I top it off with the green coolant I have on hand for a week or so? (I don't think the orange coolant was for the 2nd gens, correct me if I'm wrong..). Got to do this today or tomorrow. Also, puzzled why the reservoir look so dirty but the coolant fluid IN the radiator looks fine)

The reservoir has very little flow into and out of it, sediment will build up in that over time, it's no big deal. That's almost easy to clean out, pull the drain hose off of it with one hand, with a pan underneath to catch most of what comes out. Use a water hose and spray into the reservoir, with one hand covering the opening above the hose sprayer(to keep you dry). Then it's clean, push the hose back on, and fill it as needed to the cold level mark.

The coolant you have is likely fine to mix something new with it, the odd chemical kind is not common and I doubt you have that. So depending on what the low temps will hit, you can add as needed with the green, or the yellow cheap Prestone we mentioned before.

I had my first car with about that same level of anti-freeze in 1981, when the low one night hit -24*, no harm at all. I think the low temp has to be well below the actual coolant rating, for a long time, to freeze it and crack something(the plastic tanks are the weakest links).

If you are very worried, it's not hard to drain some coolant out, and refill with pure anti-freeze to lower the rating of the coolant. The petcock at the bottom right rear corner can be loosened with any decent pair of pliers, and a drain pan.

 

[J_C]

In some regions (esp high humidity) there can also be an issue of fungus growth in the reservoir while in the radiator it gets too hot for it to survive.