Antifreeze Type?

[mcgc0]

Searched for the correct or best type of antifreeze to use in my engine following a complete drain and thorough flush through. I will mix 50/50 with deionised/distilled water.

Surprised to see so many types out there. From what I see and read so long as it's phosphate-free then that's a start. Most current or modern antifreeze types are red/orange/purple in colour, usual ethyleyne-glycol based and with silicate inhibitors. I know for sure you can't/shouldn't mix types.

Some of the 944 techs out there recommend Prestone Dexcool (US-only, expensive). Otherwise it seems Comma antifreeze from Halfords. When I look at the data sheets for the many Comma concentrates there is the G48 given as for Porsches up to 1995 (but this seems to be the older blue type). Then there is G40 for recommended for Caymans, Boxters etc and of the 'red' type. Why? if still an all alloy engine why the difference? Might in the end just go to an OPC and get from there and take a hit on the cost.

What do you use?

 

[scubadick]

As far as the European passenger car market goes there are
3 types of modern antifreeze: a silicate technology based
product (Xstream® G48), an OAT (Organic Additive Technology)
based product (Xstream® G30) and a silicated OAT based
product (Xstream® G40). For certain applications there is
Xstream® G05 which would typically be used in heavy duty
vehicles. When compared with the more conventional coolants,
as well as lasting longer they also protect better and are
designed to be more compatible with all the different metals,
plastics and rubbers you find in a modern cooling system.
However, these high performance products use different
additive technologies to protect the cooling system from
corrosion. Different manufacturers have different requirements
and to cover the vehicle parc we need 4 different antifreeze &
coolant products. Coolant protects against freezing by lowering
the freezing point, it protects against overheating by raising the
boiling point and it protects against cooling system corrosion,
but only when it is mixed correctly with water.
The Xstream® range of coolant products are also OEM (Original
Equipment Manufacturer) approved and cover a wide range of
specifications. Commodity products like our Super Coldmaster
or Super Longlife Red have no such approvals and meet only
the industry minimum standard of BS6580: 2010.

I have reproduced the above from the Comma Oil pdf.
This is the best that I can offer, and suffice to say I have the G40 in my Boxter.

 

[Waylander]

G48 recommended by EMC Motorsport
G48 the same from Comma website

G48 I have in mine

 

[mcgc0]

Thanks Both,

Had a good chat with EMC about many things and they seem to be using OAT also. That said, I went deeper into some other coolant reading. Much these days is fucussed on harder working diesels and coolant that is happy at those temps (CI engines and all that). Front engined transaxles stopped in '95 for all models and that too is where G48 is recommended up to for Porsche, and no doubt following clarifiaction from Porsche. I could go for later G40 I guess but someone with more R&D to hand qualifies G48 as the correct choice for 4 cyls pre '95 so I'm good with that. Blimey, would never have thought coolant chemistry was a bit of a minefield.

A trip to Halfords this afternoon and I have 4 litres of G48 concentrate and 5 litres of deionised water. 968 handbook gives factory exit as a mix for temps -30oC as 45%/55%, so will aim for that, if that was the baseline to start with.

EMC interestingly gave me a scary story of avoiding wrestling with the crankcase coolant drain plug - customer trying too hard to loosen off cracking the crankcase! I will leave in place and drain from the usual other places.

 

[vitesse]

I just buy the pink dearer stuff from ECP £13 /5litres-dilute it 50/50 & use it both 924S's & the BMW
Can't see that de-ionised water is any great benefit in any of these "old" engines-if our tap water is good enough to drink then in my view,it's good enough for inside the engines

 

[Waylander]

the best of all is rain water,

its soft as anything, has no chlorine or anything else in it, just filter through one of ya Mrs stockings and your good to go, i use rain water to wash the car as well, no nasty white marks on the glass if it dries to fast

 

[scubadick]

G48 is suggested for your 968 as it is fine for models upto 1995 (as mentioned by mcgcO) After that date Comma recommend G40 for Porsche vehicles after 2010. Don't ask what happens between '95 & 2010[8|] I can't find the answer!

 

[mcgc0]

Hard water, no. Soft water, yes. I only have to look at what hard water calcium and other deposits have done in the past to my boiler, radiators and tap seals. In the car not so good (unless system flushed regularly). First thing I did when moving house and finding out it was a hard water area was to install a large domestic water softener. Now down to <4ppm from 160ppm, so will flush the engine through with tap water for a while. I got the 5L bottle of deionised water because it was only £3.50. I could have used my tap water to mix with but at £3.50 it's cheap peace of mind.

Mine already had a new water pump and thermostat replaced just before my ownership. Plently of rennlist stories on coolant woes and parts damage over a long periods of not changing.

 

[scubadick]

Absolutely, you’re spot on. As a retired heating engineer I know full well what hard water can do to heating / plumbing systems. It may be ok to drink, but when we have done so we do not then heat it to 80-90 deg. C