radiator blew again, and with a vengence

[evildragon]

I had a leak a while ago, and stopped it with Barrs.. Today when I arrived at school, another student told me my car was smoking. I popped my hood to find steam coming out of the old crack on the radiator, and green anti-freeze all over the PCM and air filter.

I made it to my mothers house via a water bottle (had to put in 900ml!!!!!!!), and am going to be driving to my home tomorrow...

here's the thing, the whole time, the temp gage on the dash said the following (my ASCII art is bad)

[C---------------F]
[----|------------]

So, I obviously have a lot on my hands. So, what do you guys think of the above? Also, should I replace the hoses, water pump, and them while im at that, do optispart, plugs and wires?

[silicon212]

Originally Posted by evildragon

I had a leak a while ago, and stopped it with Barrs.. Today when I arrived at school, another student told me my car was smoking. I popped my hood to find steam coming out of the old crack on the radiator, and green anti-freeze all over the PCM and air filter.

I made it to my mothers house via a water bottle (had to put in 900ml!!!!!!!), and am going to be driving to my home tomorrow...

here's the thing, the whole time, the temp gage on the dash said the following (my ASCII art is bad)

[C---------------F]
[----|------------]

So, I obviously have a lot on my hands. So, what do you guys think of the above? Also, should I replace the hoses, water pump, and them while im at that, do optispart, plugs and wires?

Definitely time for a new radiator. Might as well get the hoses too, while you're in there. Don't worry about the optispark unless it's giving you problems - however a new set of wires can't hurt. Plugs can't hurt, either, just make sure you gap them properly.

[evildragon]

Originally Posted by silicon212

Definitely time for a new radiator. Might as well get the hoses too, while you're in there. Don't worry about the optispark unless it's giving you problems - however a new set of wires can't hurt. Plugs can't hurt, either, just make sure you gap them properly.

well i don't know how optispark is doing.. it still hesitates, but im thinking about just replacing the ignition module first..

what about a new water pump? would that be worth it too?

and what do you think of the temp guage, is that a normal position for the 94 caprice? i'd think it would be at half.

[Blue Bowtie]

About 30% of full scale is normal. With a stock (180ºF) thermostat and fans set up to switch on at 205ºF, that's about where it stays on my '94.

I'd second the vote for a replacement radiator, and since you're going to drain and flush everything anyway, changing over to DexCool might be worth the effort. It's worked out well for me - I've been running it since June of 2000 (you do the math) and have had no problems.

[silicon212]

Seconded on the Dex-Cool. I've been running it exclusively in my cars (the '75 Grand Am first and now the Caprice) since 1997, again no problems.

[PeteA216]

I know I'm about to sound like an ignorant idiot, but what is Dex-Cool? I've heard it before, but never thought to ask about it.

[Blue Bowtie]

Organic Acid Technology PEG-based coolant. The base is the same as the older "permanent" antifreeze solutions, like Prestone, etcetera. The difference is in the corrosion protection package.

[Blue Bowtie]

BTW - There is no such thing as a "stupid question." There is, however, an abundance of stupid answers.

[PeteA216]

There is, however, an abundance of stupid answers.

Hahaha, so you said something before about a conversion. Is converting a system not as simple as just draining the old stuff, and putting Dex-cool in? Also, does Dex-cool have any cooling advantages as opposed to the old fashioned coolant?

[evildragon]

I've did searches on DexCool, and noticed a lot of complaints about it, and lots of money on repair.

I really don't have the money to invest in any possible damage in the future. I already can barely afford fixing my car, and almost thought of selling it to get a working used car.

I don't want to chance DexCool until people stop complaining about it.

[Blue Bowtie]

The older style coolants used silicates, phosphates, and/or nitrates to coat the metal surfaces in the cooling system and prevent corrosion. These work rather quickly to build a protective coating. However, they also dissolve and break down more quickly, which is why they need to be flushed clean and replenished every two years or less. DexCool and other OAT (silicate and phosphate-free) formulas use organic acids which etch and wick into the metal surface and coat it harder for better protection. The process takes longer, but the protection is better and longer lasting. As a result, deposits form much more slowly, and metal is not dissolved or leached from the cooling system. The DexCool also has other anticorrosion and lubricating additives that make the concentrate less viscous and have a greater latent heat capacity (it absorbs, holds, and moves slightly more heat energy).

From what I've learned, the two coolants are completely “compatible.” Just like the advertising on the Prestone label states, they can be mixed without causing any serious adverse effects on boilover and freezing protection.

Unfortunately, while mixing the two will not sacrifice boil and freezing protection, it can cause the silicates to precipitate out of the solution, resulting in sludge formation and potential blockage of small passages. Also, the reaction between the additives tends to compromise the longer term corrosion protection of the acids. As soon as you add silicates to the mix, you'll have to flush every two years or more frequently instead of five years.

GM was way ahead of the curve on this one. Their vehicles started getting DexCool in 1994. As of 2005, most other manufacturers have since switched to some form of organic acid technology coolant for their original fill and recommended refill.

The disadvantages are the slightly higher cost, slightly lower availability, and the tendency of the coolant to wick through the smallest openings (similar to diesel fuel leaking through connections which would normally hold gasoline). The same molecular adhesion that allows better corrosion protection and heat absorption properties also makes it seek out any marginal seals or openings.

Another disadvantage is that air in the system can cause a reaction which depletes the acid and causes the solution to precipitate out solids, creating sludge. As a result, the cooling system must be very tight system to use it. As mentioned, it will wick out of any opening, and it doesn’t like air and heat together.

Furthermore, if you ignore the required maintenance, you will see more deposits forming in a system with DexCool. DexCool will precipitate solids in a system over time, especially as it nears the end of its service life and pH increases, so cooling system service is imperative unless you want to find an orange/brown “mud” in the recesses of the system. The same is true for regular PEG antifreeze, but in two years instead of five.

I don't own a vehicle that doesn't currently use it, including all those made before 1996. I use it since too many of my vehicles sit in storage for extended periods and I'm tired of changing heater cores. After changing the second heater core in my '86 T/A at 33K miles, I bit the bullet and changed. I haven't had to touch the cooling system since July of 1997 other than to drain and flush every five years, and I'm crossing my fingers.

Despite rumors to the contrary, DexCool is probably no better or worse for ferrous metals protection than common polyethylene-glycol based antifreeze - as long as you follow the correct service interval for either type. It IS better for non-ferrous metal protection, so aluminum will last a lot longer. What it DOESN'T do is leach metal ions from the system when mixed with water. Plain PEG won't inhibit the water's tendency to dissolve metals as well as DexCool, so the coolant mixture can protect longer. If you monitor the pH and dissolved solids (conductivity) of the fluid as part of regular maintenance, you can get the advertised 5-year life without any problems. If you ignore and neglect the necessary maintenance, it can haunt you, just as any other system would.

For a fairly in-depth look at the potential problems, check here:
http://www.aa1car.com/library/2005/us90554.htm

If you search for information about it, you'll find many anecdotal stories from people (even auto technicians) who believe that it causes clogging, sediment, leakage, and all sorts of problems because they've "seen it for themselves" so often. They problem is that they usually don' know what they are seeing. If they would simply perform an analysis of the "bad" coolant they would probably understand the problem. Even though it has a longer life, periodic checks are necessary. If you neglect it beyond that point, you'll have the kinds of problems that many people are describing - just like you would if you neglected any other coolant for that long.

Whenever you work on a cooling system, be aware of proper fill level and check it regularly after the system is refilled. It is normal for the cooling system level to drop due to a natural tendency of the water used in the coolant mixture. All water, except deuterium oxide (heavy water), has an affinity for air molecules. Until the water is heated enough to drive off the air molecules (deaerated) it will bubble out air slowly until all the dissolved air is gone. In a cooling system, this can take a week or more. Every time the coolant warms up, more air is driven off, causing the liquid level to slightly decrease as the air bubble is created. Large commercial boiler installations have separate deaerating vessels to prepare the make-up water so that an air bubble isn't developed inside the boiler (that would be a very, very bad thing).

If you use the air bleeds provided in many newer cooling systems when refilling, and keep topping off the system after refilling, this phenomenon should stop after a week or so. If it really bugs the crap out of you, you can pre-boil the water that you use to mix the coolant before you pour it in the radiator, so that this effect will be minimized. That would be pretty anal, though.

And you really need to thoroughly flush the system before refilling. Consider a slightly "leaner" mixture, too. About 40/60 is usually best for cooling and protection, as long as it meets the freeze protection you can realistically expect in your region.

[silicon212]

Blue Bowtie also didn't mention that the Dex-Cool coolant is easier on water pumps - the silicates in regular PEG antifreeze are abrasive and will eat away at the water pump seals and bearings. Dex-Cool antifreeze tends not to do this.

[PeteA216]

Very informative... thanks! The engine from the '92 pickup I've taked about in my other thread has just recently had a professional, very extensive coolant flush. I just drained it all when pulling it from the truck, and wow. From what I can see externally the inside of the thermostat housing and water pump are so clean you can eat out of them (not literally). There seems to be very minimal corrosion as well, in comparason to some engines I've seen in the past. I may put Dex-Cool in when I drop the engine into my'84 Caprice, it does sit all winter long.

[mike561]

My pontiac grand prix said to use dex cool but it was when i used to talk to the guys over at those forums, they said most of them have done away with dexcool and use prestone extended life instead, as dexcool leaves a sludge after a while too. thats just what i know...