Just changed radiators on my 98 C2. I had topped up the water a couple of times before I changed radiators and I lost some coolant in the rad change. I rang OPC and ordered 9litres of antifreeze which they have delivered (God it's expensive!!!) But it's red/pink and not the green stuff that's already in the system. Do I have to flush out all the green before adding the pink or is it compatable?
coolant change
- Thread starter whizz1001
- Start date
They are supposed to be compatible. When I replaced my radiators, I left the small vent tube at the radiator off and slowly refilled the system until coolant emerged from the tube then reconnected it. I had no problems with airlocks and the refill amount was exactly as that drained. Some cars are more prone to airlocks than some.
Although the colour changed, they are both supposed to be OAT (organic acid technology) coolants. They are also known as silicate-free coolants. This is why they say it is a lifetime coolant and both are compatible. In the old days, the blue/green coolants were silicate ones and the pink ones were OAT coolants. Today, the other category is Hybrid OAT (mixture of OAT and silicates) and colour is no longer category dependent although generally most HOAT/OAT coolants are pink/red/purple. Silicate coolants wear out due to the silicates being used up hence 2 -3 yearly coolant changes. This is not supposed to happen with the OAT ones. Although HOAT coolants have silicates and OAT additives, if you mix a OAT one with a silicate coolant, it turns into this nasty brown sludge. However if you are confident that the yellowish coolant in you Porsche is the original fill then it is fully compatible with their latest pink one. Its the same with the VW/ Audi coolant where the older G12 coolant was pink but the new G12++ one is purple but both are compatible.
Just to add to the confusion, they all tend to be ethylene glycol based but it is the additive package that is different i.e silicates, mixture of silicates and OAT (HOAT) or silicate-free (OAT).
Silicate coolants can have nitrites, amines, phosphates or none (NAP free). OAT ones tend to be known as silicate, nitrite, amine and phosphate free coolants.
Just to add to the confusion, they all tend to be ethylene glycol based but it is the additive package that is different i.e silicates, mixture of silicates and OAT (HOAT) or silicate-free (OAT).
Silicate coolants can have nitrites, amines, phosphates or none (NAP free). OAT ones tend to be known as silicate, nitrite, amine and phosphate free coolants.
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