Classic VX cooling and antifreeze

[andi4eyes]

Another question about my new to me Classic VX ex Grad racer. This time about cooling and coolant.

On the weekend I realized that the car doesn't get warm. I'm sure that was accentuated by the colder weather compared to when I drive the car last. I didn't think about that before but this must mean the car runs without a thermostat. For my drive on Sunday I taped up most of the nose cone which helped to get the temperature close to 80. Next time I will tape up a bit more or block the radiator itself to get the temp a bit higher still.

I have ordered a febi thermostat for that GM engine code that should arrive mid week. Am I correct in thinking that I should only have to top up my coolant and be done with it or do I have to bleed the system somehow?

I hope the coolant question isn't as controversial as an oil question ;-) I've noticed that the coolant in the car is (very) orange. Given that it is a Caterham serviced by a Caterham race support shop I concluded that this might be the Motul Inugel Optima that CC sells. Or another orange OAT based antifreeze. All IAT antifreeze products I found seem to be blue. Now given this engine is what I would call classic I would have thought I should use a IAT based antifreeze. I do have a new ally radiator, might that be a reason why it's okay to run a OAT based coolant? What are your thoughts on that?

 

 

[Tazio]

Alloy Rad, use the blue stuff.