Radiator additives?

[marauder307]

Was ordering my replacement Autometer guage the other day, and noticed that Royal Purple also makes a radiator additive in addition to their oil. I've also seen this stuff called "Redline WaterWetter" sold by Steeda that supposed to do about the same thing; I guess the big idea is that either of these additives are supposed to help your radiator work more efficiently, or something, and consequently help the engine run cooler.

Has anybody ever tried one of these additives, and if so, do they actually work? I'm thinking about getting the Royal Purple stuff...

[frdwrnch]

I had a cooling problem on my '65 Falcon Wagon and used the water wetter as a patch. It really worked! Made about 15 deg (F) cooler. Then I had the radiator serviced (rodded out) and use a Gano coolant filter and have had no more problems.

[Cobra25]

I used the Red line product and seen no difference at all.

[RF Overlord]

I used the Red line product and seen no difference at all.

This is probably why:

Cooling System Fluid Stabilized Temperature
50% Glycol/ 50% Water 228°F
50/50 with WaterWetter 220°F
Water 220°F
Water with WaterWetter 202°F
(from Red Line's web site)

Notice that the temperature differential between a normal coolant mix alone and the same coolant mix with WaterWetter is only 8°...

[Heavy351]

I used to use it on my last car with straight water. If you use any antifreeze you loose the benefits of it. I believe this works by breaking down the surface tension of the water and increasing the thermal conductivity.

This is all wonderful if you see wild swings in the temps and using it made driving in heavy traffic possible for me with the heavily modified motor and otherwise stock cooling system.

But in my Marauder, I cannot recall seeing the temp needle move ...ever. Now granted this is a factory guage but I get the feeling that in a stock capacity, we have more than adequate cooling capacity.

However, when you use a cooler thermostat or a supercharger, the radiator may not be as efficient at getting rid of the extra heat generated (those with aftermarket guages would be better to ask on this) The water wetter might be beneficial in giving you a bit of "cushion" thermally speaking.

Because this works best with straight water, you will need to add coolant for the winter months where you might leave the car outdoors for more than a few hours below freezing.

[purelux]

If you use the min they recommend 30% coolant it will still have an effect and have enough protection to keep from freezing or corroding or boiling over. Also on a newer car the gauge checks the water temp not the engine temp and isn't dead on accurate and usually has a margin of several degrees where it doesn't move but the temp can move around. The watter wetter causes the water/coolant to more effectivly pull heat from the engine and helps to prevent hotspots like around the heads that get hot enough to cause detonation and can keep the colant from cooling the metal there due to a heat pocket. If you read what they explain it doesn't lower the water temp which is what most gauges look at not the temp of the block. What it does is help the water to better pull heat from the block. Your thermostat and fan are set to keep the car whithin a certain temp range and a fluid isn't going to change that nor does it claim to though it is confusing if you don't read there whole writeup and just look a the bottle. Also you need coolant in year round as corrosion doesn't take the summer off and the watter wetter and or just water don't have the conditioners/lubricants that the coolant does either. Also the boilover protection isn't there either.

[David Morton]

Having worked as an ASE Master Tech and seen many cooling systems my experience has shown the people that get the most mileage from their entire cooling systems are the ones that do the "drain and fill" every year. Be it Ethylene Glycol or the old Propylene Glycol type the basic fact remains that time, heat and impurities will cause any coolant mix to break down gradually turning it into the enemy of seals, hoses and radiators. If you want your cooling system to last and be trouble free, change the coolant every year. Remember a drain and fill isn't going to get all of the old fluid, so doing it every year will keep the old stuff diluted enough to have negligible negative effect. And change that thermostat and check the hoses at 50,000 just to be on the safe side and certainly if you notice the temp guage riding any higher than normal. That factory guage is pretty accurate and should run in the same spot if your thermostat is working properly. Never use "flush" products as they introduce dangerous contaminants into the system, read the labels, they always want you to flush the system with water to get their product out before you fill the system with what's supposed to be there, coolant.

So my advice is, save your money. Just buy a couple of gallons of the right type of coolant every year, and drain your system and fill it back up with fresh mix. In Florida, I do it every spring before the hot weather hits. Up north, do it every fall before the first frost. My customers that did the yearly drain and fill routine probably averaged 100,000 miles before they had their first problem, if you don't count the thermostat change. $10 a year keeps my cooling system in top condition. Folks that keep a manicure can pay for a drain and fill for about $50.