Coolant bleeding procedure.

[rotorwings]

Could someone point me to some documentation on the correct procedure for bleeding the coolant system in a Duratec Caterham?

The heater sits higher that the rest of the cooling system - is there a trick to bleeding system that have a heater?
Does the blanking plug on the radiator function the same as the radiator cap on a normal car? Should the system be bled and filled via the blanking plug?

Sorry, these questions sound silly. I have bled cooling systems on normal cars before, but there are usually a few extra tricks with Caterhams and I just want to be sure I don't make any mistakes.

[DCL]

Bleeding the R400 can be problematic, particularly if the water rail on your car dips below the height of the radiator. Don't worry too much about the heater - any air in there will work its way out once you start driving it.

You may find the the level in the header tank goes up and down. I eventually diagnosed this to air being trapped in the top of radiator which displaces coolant and makes the level appear higher. Again this can cure itself when driving but, as the problem kept reoccurring with me, I added a second auto bleed to the bolt in the radiator - problem solved

Edit just to add, you should fill using header tank and bleed the radiator with the bolt.

Edited by DCL on Tuesday 25th November 14:29

[downsman]

I don't have a Duratec, but the build manual fory Sigma car said to fill through the top pipe to the heater valve. I measure how much comes out. Then fill into the pipe using a funnel until water comes out of the heater.

I reconnect the hose and fill to correct level in the expansion tank. At this stage there is usually about 1 litre left to go in. Squeezing the rad hoses gets the water moving enough for most of the air to bleed out. I then run the engine and the level drops in the tank enough to get the last 0.25l in.