Water vs coolant

Hallo , there are some difference between coolant and water ,but not critical , if your car runs hot the problem cannnot be coolant(IMH)

 

With a 15 pound cap, water boils at 257. With 50/50 mixture it boils at 265. But your overheating is not related to water vs 50/50.

 

I have found (on recommendation) that using a lessor quantity of coolant allows the system to more quickly dissipate heat. I can testify that by following this advice my car did immediately run cooler even on very hot days.

 

It's called heat capacity of a fluid. The heat capacity is the amount of heat required to raise the temperature of an object or substance one degree. Water has a higher heat capacity than glycol (takes more heat to raise the same amount of water 1 degree compared to glycol). So, as you dilute water with glycol, the heat capacity of the mixture decreases.

So, it is better to use only the blend of glycol and water to protect the fluid from freezing. There is also a boiling point increase with the mixture, but that is not really important as your radiator cap will hole pressure, which also raises the boiling point of water.

 

Am I the only one thinking there is air in the system and it needs to be bled? Also going to a colder fan switch in my car helped.

You want coolant as it is the lubricant for the water pump.

 

Change out the radiator and you will never have another problem. Look up Ferraripilot, he makes a racing style unit that is simply fantastic. I can drive my car in a 5 mile parade when it's over 100 degrees Fahrenheit with no problem.

 

You don't own an 84 or 85, that's why. Carb 308 never had a cooling problem, 84 and 85 cars did.

 

In answer to the OP's question, yes water only will help. I worked in those years at a dealer where summer temps were routinely in the triple digits and 84 and 85 308s had difficulty in the summer. Ferrari redefined overheating by increasing the coolant pressure cap rating and saying if it didn't boil over it was not overheating no matter the gauge reading.

A 25% mix of antifreeze or straight water with Redline watter wetter helped quite a bit. Better, higher capacity aftermarket fans or a larger radiator would be better still.

Those cars are why the 328 got a complete redesign for the cooling system.

 

Maybe, but at least not all 84. My 84 QV never had overheating problem in 10 years of owning it, original Radiator. I had not replace my fans, thermostat, and water pump since I bought it ten years ago. Even driving it here during LA rush hour traffic at 90+ she still runs normal (195-198) then cools down as you speed up, and this is with 50/50 mix.

 

I have also found the heat transfer being faster using less coolant, say 20/25% coolant instead oif 50/50, warm climate countries dont need so much 'anti freeze '

Jan, does the car steam/ boil or is it only the high temp indication on the guage that worries you?

Regards

 

Another friend of mine complains about the heat on her 81 GTSi

 

Another friend of mine complains about the heat on her 81 GTSi

 

Oops, sorry for quoting myself

 

Excellent. What was the cooling system design change? Both engines were about the same HP and thermal efficiency so heat production would have been about the same.

 

They were not the same power. The 84-85 made more than the other 308's and the 328 was higher still hence the need for greater cooling.

The design change? The grill in the hood on the QV was found to be an improvement but not near enough so further redesign to the front of the car to provide much greater air ingress and egress, much larger radiator set at an angle. Even with the angle it required revised body work at the nose to accommodate it. It also had bigger ducted fans and the A/C condenser was relocated to eliminate that cause of restricted air flow. They did not redesign the nose and nose only to give the designers some practice. They went to great expense to fix the cooling issues.

 

Fortunately for you, you live in a mild climate. My 84 isn't always happy down here in the deep south during summer.

The last place I want to be is stuck in Atlanta on I-285 in July. Ask me how I know (about 2 dozen times over the past twenty years)

 

I think simply putting the fans behind the radiator and pulling the air through it was as good a design change as anything.

 

Tommy, you are right, being hot like here in SoCal is one thing but being hot and humid is another.

 

I have recently put in a 1/3 coolant 2/3 water mix i purchased from an auto store and early indications are it runs cooler than 50/50. But i will know after my next long drive.

 

Question Brian, why only 84 and 85 but not 83 QVs?

 

In the US the 83 had different smog equipment and a slightly different state of tune to meet US emissions. We never had temperature problems with them.

 

Ahh thank you

 

That's two of us, my 85 down here in Florida, traffic or not has never over heated, Summer temps often get up to 100*
I have 25% antifreeze, and well water. My gauge has never been over 210* I believe my entire cooling system is original.

Maybe high humidity makes a difference?

 

Make it three. 30 years of ownership of my 85 QV and never any kind of over heating. Original everything, including water pump. In fact, I always heard it was the other way around. The early QVs tended to run hot and there was a change made some time in 84 to correct that and many 83s and early 84s were retrofitted.