Well I did replacing the coolant over the weekend (don't mention air locks). I put in 2l of red (fetching pink actually)anti-freeze and eventually 5l of H2O. Is this enough anti-freeze itself (just under 30%) to cope with the UK's winter temperatures'? This far south of Edinburgh I wouldn't expect these to drop below about -4c or -5c.

You should really do a 50/50 mix of anti freeze to water, that should cover you to around -30ish which is about right. You may need a Hydrometer to check the freezing point of your anti freeze though but always best to do 50/50.

Tony

Yes what Tony said. We usually run 50/50 here in New Zealand and it hardly gets below 5 degs where I live. Plus anti freeze has a anti corrosion substance which is important for the alloy parts of our engines, if you don't have enough your parts will corrode faster.

Dan