The V8 Owners Forum -

I have Rover 3.5v SD1 motor circa 1980 and am wondering which is the most suitable coolant for this engine ?

Best coolant pure water.

But if you are in cold climate you need an antifreeze.
And most antifreezes also have inhibitors and lubricants for pumps etc.

Ian

Blue antifreeze - 50/50 mix with water.

Chris.

Thank you, I will go for the blue mixed 50/50 with water as often have quite heavy frosts during the winter

Very important to use the correct anti-freeze all year round - or an inhibitor to prevent corrosion.

I read somewhere that there are three different types of coolant recommended for V8s, depending on their age? Different colours too? I’ll try and find that info…

Although my P38 used the pink OAT stuff, after a while I changed to the blue glycol stuff with no negative effects.

Chris.