A bit hot under the collar...

[terryp]

Rohan
What amount of antifreeze are you running?
I bought some water wetter. According to the bottle........Dyno test results
50% Glycol/50% Water 228 degrees F
50/50 + Water Wetter 220 degrees F
Water only 220 degrees F
Water & Water wetter 202 degrees F

Because it gets a bit cold here (-15 degrees C) I run 50% antifreeze, so now don't really think its worth it???

Terry

[GrUmPyBoDgEr]

Heat transfer is a complex subject, so much so that many Radiator Manufacturers rely on experience more than the written Laws of Physics.
I was once asked to write an in depth report on an Oil / Coolant Heat exchanger that I had developed for a Car engine together with a major German Supplier.
That Report didn't get written because the required Calculations were never forthcoming.
However it was part of my job to optimise the Design by experimenting with the Coolant flow across the Heat Exchanger; the Oil flow across the Heat Exchanger, could not, for obvious reasons be regulated.
By regulating the Coolant flow the function was optimised & the final Dimensions for the Coolant side of it defined.
Coolant needs to be in contact with the Surfaces it is cooling long enough in order to absorb the maximum amount of Heat & it also requires time to disperse that heat in the Radiator.
If the Coolant flows too fast that will not happen.
Increasing flow rates is not the Universal answer to improved Cooling however by Hook or by Crook in some applications an improvement may well be the result.
Nevertheless the results are what's important & I know a couple of Racers that have assured me that they've measured Coolant Temperature drops after putting "Water Wetter" into the Coolant.

Cheers
John

[GrUmPyBoDgEr]

Rohan
What amount of antifreeze are you running?
I bought some water wetter. According to the bottle........Dyno test results
50% Glycol/50% Water 228 degrees F
50/50 + Water Wetter 220 degrees F
Water only 220 degrees F
Water & Water wetter 202 degrees F

Because it gets a bit cold here (-15 degrees C) I run 50% antifreeze, so now don't really think its worth it???

Terry

Terry,

the general recommendation for Europe & other temperate Climates is 40% Antifreeze.
For Scandinavia, North America & other Cold Climates 50%
Purely a cost saving in Car production but nevertheless proven quantities over years of production.
Antifreeze stops Freezing but does not increase the Boiling point because the Water content will always boil off at 100?C at Sea level (i.e. unpressurised; 1 bar abs.)

Cheers
John

[rgh0]

Terry
I run 30% antifreeze. Mainly to help increase boiling point and for corrossion prevention. It never gets cold enough here to worry about freezing

cheers
Rohan

[terryp]

So I won't add the water wetter then.........

I do find that with the standard radiator + 71 degree thermostat + Fan Switch at 78 degrees + Kenlowe modern fan + Foam on bonnet + deflector board under rad + Triangle infills to sides + Everything moved away from inside the nose infront of the radiator. - I'm running quite cool now!!!

And if it ever gets to -30degrees ......I'll be ready!

[rgh0]

[quote="D.J.Pelly
Antifreeze stops Freezing but does not increase the Boiling point because the Water content will always boil off at 100?C at Sea level (i.e. unpressurised; 1 bar abs.)

Cheers
John[/quote]


John
Not sure that is correct. I dont have phase diagrams of water / ethylene glycol mixutres handy but I believe both the boling point increases as well as the freezing point decreases.

Certainly the makers of the antifreeze I buy claim this to be the case on their bottles and quote specific temperatures


cheers
Rohan

[terryp]

I Lied (!'ve just checked)
I have Premixed French Antifreeze made by Durand Production under the name Valco.
No info on the internet at all but the lable says good for -35degrees!!!
It also says on the lable contains between 20% and 50% ethanediol, which is rather vague!

I think I'll move back to the UK......

[GrUmPyBoDgEr]

Regarding the Boiling thingy with Antifreeze Rohan, that's something I was told & never investigated myself, nor have I read much on the subject. Working on Cooling Systems was a very short phase of my working life & one which I did not enjoy very much, hence the lack of in depth knowledge.

Terry,
stay where you are, at least for the next 10 years; Britains "Bubble" has yet to burst & the climb back up will be a hard one IMHO.

Cheers
John

[collins_dan]

I thought I would give an update on my project to replace 1 10" pusher fan (850CFM) with 2 8" puller fans (750CFM each). I have only driven it once. It was 92F (33C). Since my water temp gauge has decided to stop working properly it's hard to say what effect it is having on the water temp, but I can say that the person on left, driver (US) or passenger (UK), gets a whole lot warmer with all the air blowing over the exhaust manifold.

Dan

[RedS4]

I live in the western suburbs of Sydney, where it can get to 35C + for days on end in summer and drop below freezing in winter in the mornings...
The radiator is the standard (small) S4 fitment. I have removed the standard fan (just two blades?!) and fitted an 8" fan as a pusher wired directly into the ignition, flushed the system refilled with a quality coolant and fitted a 71C thermostat.
Cruising temp is about 80-85C, with the hottest I've seen is 98C in traffic. It has yet to be tested in an Aussie summer. I am interested in the "factory approved" additional vent holes - I'll install them if summer becomes an issue.
Maybe I'll refit the belt-driven fan (or one with more blades) as "insurance" as well.
The heater was wired shut by a previous owner - I have yet to find out why - so I currently don't have the luxury of that as an auxillary radiator...

[RedS4]

Update on my post above - after buying some new tyres I drove home in terrible peak-hour conditions of VERY slow traffic and lots of rain (which in itself can the subject of a stack of more posts elsewhere - eg interior fan's a joke - wipers "only for show" they are so slow etc... yes, it was my first wet night... ), - the temp managed to climb to 110 on occassion but I don't appear to have lost any coolant and the engine felt fine the whole time. I am beginning to wonder if the guage is not quite kosher. How does one test its accuracy in situ?

Cheers

[m750rider]

Infrared temperature gun can measure the temp at the thermostat housing at the sending unit well.

[terryp]

I've just bought one! Its fab!
My new toy, I now know the temperature of everything , well not quite everything.........

Terry

[RedS4]

I've just bought one! Its fab!

Are they expensive?

[terryp]

http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... TQ:GB:1123

?12.95 but it took 7 weeks to arrive from China, had done paypal claim before it arrived, so paid them the money on arrival!

Terry
PS Computer screen is 26.8degrees!