Heat transfer fluid? help..

[FF]

The 50 50 mix is usually for cars with 15lb pressure caps, not boats.

On many boats the pressure cap is 2-5lbs and using pressure to operate at over boiling te,peratures is never seen.

35% antifreeze the rest distilled water will give the coolant the corrosion resistance needed.

The antifreez is only 3/5 effective at moving heat , so the extra water in the mix is a cooling help.

Folks that need the 50/50 anti-freez protection , -35F are probably not on this board.

Perhaps there are some towns that have good enough water to use in cooling systems or better water that is battery grade.

But the tests for minerals would only be for one location, on one day.

At a buck a gal, distilled water is the cheapest insurance a boater can purchase.

For a cruiser its mandatory.



FF

 

[RickB]

The 50 50 mix is usually for cars with 15lb pressure caps, not boats.

On many boats the pressure cap is 2-5lbs and using pressure to operate at over boiling te,peratures is never seen.

Folks that need the 50/50 anti-freez protection , -35F are probably not on this board.

It's not about freeze protection. Changing the mix changes the boiling point at any pressure.

Pure ethylene glycol antifreeze boils at 386*F at atmospheric pressure so it is no different than the high priced stuff in that respect.

A 50/50 mix boils at 225*F at atmospheric pressure. At 15 psi it boils at 265*F.

You can mix the stuff to meet the maximum temperature you want and 50/50 is what 99 percent of the world uses as a practical compromise.

The bottom line is the higher the percentage, the higher the boiling point at any pressure but the less the heat transfer capacity. While it transfers less heat, it is thicker and harder to pump at the same time it needs to flow faster to achieve the same rate of heat removal.

Like I wrote before, this whole thing is another solution looking for a problem. It seems to have originated with truck drivers who have nothing else to think about while blocking the high speed lane.

 

[rwidman]

Volvo, the manufacturer of my boat's engine recommends a 50/50 mix of "Volvo Special Coolant" and distilled water.

That works for me.

 

[rwidman]

you are probably not wrong however if there is better for a reasonable cost, then i want better.

My point is, as far as your engine is concerned, there is nothing better. In your mind, perhaps, but not in your engine.

Let's look at this a different way: If the engine manufaturer specifies grade 2 bolts for a specific application, is there anything to be gained by using grade 8 bolts? The answer is, no.