Anti-freeze question

pebblepixie

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My hubby has got an old Peugeot 406 (I know, I know...he inherited it) anyway, it's our first car and we know very little about looking after it. He's been trying to find out about how much anti-freeze he should have in the coolant system now that winter's approaching (we live in the North East of England) but all he can find is that he should check the concentration. There's nothing he can find (and he's already googled) that tells him what the concentration should be. Even the labels on the bottles are unhelpful. Can anyone help?

Thanks
 

Pug

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As a general rule of thumb, a 50/50 mix is the minimum concentration.

Get yourself a gravity tester from a motor factors (looks like a turkey baster) and it should have a graded scale showing what temperatures you'll be protected down to with whatever mix you apply. :)
 
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airmenair

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Usually 50/50 as Pug said, but, if you want a sanity check, EVERY car should have that kind of basic information in the owners manual. If you don't have one you could pick one up from ebay or a dealer for probably next to nothing. It's a good place to start for basic car maintenance.
 

Cowboy

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As a general rule of thumb, a 50/50 mix is the minimum concentration.

Get yourself a gravity tester from a motor factors (looks like a turkey baster) and it should have a graded scale showing what temperatures you'll be protected down to with whatever mix you apply. :)


^this, cheap and simple, make sure you get it altleast down to -35 in our climate.....while it will never actualy get that cold (atleast I should hope not) windchill on a very cold night (say -15) can realy get to a car if it sits outside in an open space.
 

pebblepixie

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Usually 50/50 as Pug said, but, if you want a sanity check, EVERY car should have that kind of basic information in the owners manual. If you don't have one you could pick one up from ebay or a dealer for probably next to nothing. It's a good place to start for basic car maintenance.

He looked in the owner's manual and we've got the Haynes for it as well. Both tell you how to keep it topped up etc. but not what the ratio of water to anti-freeze should be :blink:

Thanks for your help folks :love:
 

Nabster

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There is no set ratio. What you'll find in the manual is the type it should have in it (generally the makers' own brand). The ratio changes depending on multiple factors, climate primarily, altitude if you're high up, and where you drive it (i.e. polar expeditions vs. desert romps). Start with 50/50, get a tester and see how cold it will go. You want to make sure your fluid will protect to colder temperatures than you will get. You'll have to adjust the mixture by adding either more coolant or distilled water, it's generally said not to go past 70/30 either way.

If you can't do it yourself, take it to a place that does coolant flushes and ask them to do it. If the car has never had its coolant flushed, it probably wouldn't hurt to have that done, and they should refill it with the proper mix from there and you'll be set.
 

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From Prestone

Q. What is the best antifreeze/coolant concentration for a vehicle? Can I use 100% antifreeze?

A. We recommend that you use between a 50% and 70% concentration of antifreeze. At least 50% is necessary to give the adequate amount of corrosion protection, as well as freeze/boilover protection. However, we do not recommend more than 70% antifreeze. This would cause restriction of the heat transfer capabilities, corrosion protection, and freeze protection. The concentration of freeze/boilover protection of the antifreeze mixture can be checked using a Prestone? Antifreeze Coolant Tester.
 

boganbusman

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If the car has never had its coolant flushed, it probably wouldn't hurt to have that done, and they should refill it with the proper mix from there and you'll be set.
Whoa, you gotta be careful with coolant flushes. If the cooling system is relatively clean and free of corrosion and gunk, then it should be fine.

BUT if the coolant looks nasty and really old, doing a coolant flush will probably cause a leak somewhere. Usually the water pump goes first (if it hasn't been replaced for a while).

However, in a cold climate it's neccessary to have a good coolant mixture so just be prepared for extra repairs is all I'm saying ;) Over here we don't need antifreeze so rusty systems tend to get left alone.
 

narf

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for all antifreezes i came across the 50:50 mix is for the lowest temperature it can withstand

This. Mixing significantly more than 50% AF with water will raise the freezing point - pure ethyleneglycol (aka antifreeze) will freeze at -16?C, perfect mixtures may withstand -50?C or more.

In Southampton a lower concentration will suffice, but you should consult some testing tools. To be safe without too much thought, 50/50.
 
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Pug

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Whoa, you gotta be careful with coolant flushes. If the cooling system is relatively clean and free of corrosion and gunk, then it should be fine.

BUT if the coolant looks nasty and really old, doing a coolant flush will probably cause a leak somewhere. Usually the water pump goes first (if it hasn't been replaced for a while).

However, in a cold climate it's neccessary to have a good coolant mixture so just be prepared for extra repairs is all I'm saying ;) Over here we don't need antifreeze so rusty systems tend to get left alone.

Say wut? :?
Hmm. On second readthough, perhaps you're not advising against coolant change... but it's hard to tell. :blink:

You should change your coolant every two years, as the corrosion inhibitors lose their effectiveness, leading to either galvanic corrosion (and future leaks/part failures) and/or rust buildup (with decreased cooling/more part failures), depending of the metallurgical makeup of your engine..

Leaving it because it "looks fine" is what can lead to the symptoms described in the above post, together with the most common symptom of overheating in traffic because of the decreased thermal conductivity/efficiency due to the increased contaminant in the coolant.
 

Austere

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My hubby has got an old Peugeot 406 (I know, I know...he inherited it)
Hey. What's so bad about a 406? They look very beautiful, they handle wonderfully, they're chic, they made heaps of them over a long period so in theory there should be a lot of parts and um, did I mention the fact that there's one featured in the greatest car chase sequence in motion picture history? No? Well I should have.

Anyway, no idea about the coolant. Sorry.
 

boganbusman

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Say wut? :?
Hmm. On second readthough, perhaps you're not advising against coolant change... but it's hard to tell. :blink:

etc.
The OP has just recently acquired this car, and I'm guessing they wouldn't know if the coolant has been changed regularly. Maybe the car has been sitting for a long time? Who knows.

I'm just saying that if it's already rusted up then it will probably leak once a flush is performed. Hopefully it's all good and no repairs wil be neccessary
 

pebblepixie

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Hey. What's so bad about a 406? They look very beautiful, they handle wonderfully, they're chic, they made heaps of them over a long period so in theory there should be a lot of parts and um, did I mention the fact that there's one featured in the greatest car chase sequence in motion picture history? No? Well I should have.

Anyway, no idea about the coolant. Sorry.

Did I mention it's a diesel....

No really, it's a fine, fine car but TG slags off Peugeot all the time so I was just pre-empting any piss-taking that might've come my way. :)

Anyways, no idea when the coolant was last checked but it's due a service and MOT very soon so it's probably safer - with us being car newbies - to let someone else sort it out this time.

Thanks for all your help everyone - big kisses to all of you :D
 
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