What Antifreeze should my C8 have?

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PeteC8
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What Antifreeze should my C8 have?

Unread post by PeteC8 »

As above, the coolant appears to be a yellowish colour, on looking in car parts store there seem to be a bewildering array of colours and contradictory fitment information!
Can someone tell me which is correct? I intend to flush and refill.

Many thanks!
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Doo
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Re: What Antifreeze should my C8 have?

Unread post by Doo »

PeteC8 wrote: 26 Oct 2022, 10:09 As above, the coolant appears to be a yellowish colour, on looking in car parts store there seem to be a bewildering array of colours and contradictory fitment information!
Can someone tell me which is correct? I intend to flush and refill.

Many thanks!
Generally, it should be OAT (Organic Acid Technology) which is orange. I wonder if someone mixed in some blue :shock: :shock: I would be inclined to drain it out, flush through with water, then connect everything back up and put in new antifreeze. It's generally a 50/50 mix, but coming up to winter you'll get away with 60% OAT & 40% water.

I's fine to have a bit more coolant than water. I do it and it doesn't harm any of our vehicles. I get astonished at Aussie truckers wondering why their engine blows hoses and overheats... I end up swearing at the tv, telling them to add coolant as it raises the boiling point ....
Has anyone seen the plot? :?
jscadden
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Re: What Antifreeze should my C8 have?

Unread post by jscadden »

It is also a good idea to keep the antifreeze topped up all year as it contains anti-corrosive chemicals which prolong the life of the cooling system.
John

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PeteC8
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Re: What Antifreeze should my C8 have?

Unread post by PeteC8 »

jscadden wrote: 26 Oct 2022, 15:09 It is also a good idea to keep the antifreeze topped up all year as it contains anti-corrosive chemicals which prolong the life of the cooling system.
Thanks very much John.
When I got the car earlier this year I dropped some antifreeze due to having to remove a pipe to get access to a stroppy starter motor!
I topped up with water, every time I looked into the subject I got confused, but now the cooler weather is approaching, I needed to get the experts advice!

PS: I understand the benefits of keeping the antifreeze strength up, this hasn't been sitting easy on my shoulders!
PeteC8
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Re: What Antifreeze should my C8 have?

Unread post by PeteC8 »

Doo wrote: 26 Oct 2022, 11:59
PeteC8 wrote: 26 Oct 2022, 10:09 As above, the coolant appears to be a yellowish colour, on looking in car parts store there seem to be a bewildering array of colours and contradictory fitment information!
Can someone tell me which is correct? I intend to flush and refill.

Many thanks!
Generally, it should be OAT (Organic Acid Technology) which is orange. I wonder if someone mixed in some blue :shock: :shock: I would be inclined to drain it out, flush through with water, then connect everything back up and put in new antifreeze. It's generally a 50/50 mix, but coming up to winter you'll get away with 60% OAT & 40% water.

I's fine to have a bit more coolant than water. I do it and it doesn't harm any of our vehicles. I get astonished at Aussie truckers wondering why their engine blows hoses and overheats... I end up swearing at the tv, telling them to add coolant as it raises the boiling point ....
Thanks very much for the info, orange it is then!!

When I got the car earlier this year I dropped some antifreeze due to having to remove a pipe to get access to a stroppy starter motor!
I topped up with water, every time I looked into the subject I got confused, but now the cooler weather is approaching, I needed to get the experts advice!

PS: I understand the benefits of keeping the antifreeze strength up, this hasn't been sitting easy on my shoulders!
PPS: I try to avoid all those staged semi reality programmes now as I used to react like you and while the scales of size and accessibility of Australia is a fascinating subject, my blood pressure comes first!!
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MattBLancs
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Re: What Antifreeze should my C8 have?

Unread post by MattBLancs »

Doo wrote: 26 Oct 2022, 11:59 I's fine to have a bit more coolant than water. I do it and it doesn't harm any of our vehicles. I get astonished at Aussie truckers wondering why their engine blows hoses and overheats... I end up swearing at the tv, telling them to add coolant as it raises the boiling point ....
I've been racking my brain as something was niggling me about the above! Bit of Googling helped, you are quite correct antifreeze does increase the boiling point.

But there is a negative - antifreeze has a lower specific heat capacity than pure water, so you are loosing a little cooling capability at an increased concentration.

Which is the dominant factor I'm not sure?
:)

https://www.motortrend.com/how-to/glyco ... r-coolant/

Matt
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CitroJim
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Re: What Antifreeze should my C8 have?

Unread post by CitroJim »

MattBLancs wrote: 26 Oct 2022, 18:55 But there is a negative - antifreeze has a lower specific heat capacity than pure water, so you are loosing a little cooling capability at an increased concentration.

Which is the dominant factor I'm not sure?
I can only speak of blue ethylene glycol Matt but the recommendation is not to exceed about 35% as cooling efficiency becomes compromised...

It's interesting to see that some users of 'waterless' coolant have encountered overheating problems in classic cars... Presumably for the same reason. They revert back to ethylene glycol and problem solved...
Jim

A bit of a Citroen AX fan...