Coolant bleed procedure

[nesty]

I have just replaced my thermostat & Radiator.

My new thermostat has the bleed valve in it. Do I still need to do the bleed procedure below? Or is the valve in the thermostat, just to assist the procedure?

[To bleed the air you must take the top off the header tank and run the engine with the heater on full blast till the cooling fan cuts in, this should push all the air out of the system and then put the cap back on, thats the way I do it anyway! Must say though this would only need to be done if the coolant has just been replaced]

 

[pollyp]

the little valve simply makes it abit easier to purge some of the bubbles out of the block whilst cold.
you still have to follow the same original procedure to get the rest of the air out of the whole system.

 

[nesty]

the little valve simply makes it abit easier to purge some of the bubbles out of the block whilst cold.
you still have to follow the same original procedure to get the rest of the air out of the whole system.

OK cheers many thanks. Will have a go at it tomorrow!

 

[nesty]

OK. I did the below procedure. However, I couldn't get the fan to come on. Despite reving it at a stand still for 10-15mins. (is a cool day today).

The temp gauge stayed in the middle throughout & getting nice hot air from the heater.
I can only assume it's a happy engine & coolant system now?!


[brim the rad with coolant and leave rad cap off.
turn heater dial on hot to bleed the heater core too.
start engine and run till it goes upto normal temp. the thermostat would then open to let coolant flow up into the radiator along with any trapped air that was in the system.
rev it afew times to further agitate air trapped inside to bubble up.
as the level in the rad goes down, fill up with coolant.
when no more bubbles appear, fit the rad cap back on, turn heater dial back to cold.
watch the temp gauge stays in the middle. when it gets too warm the fan should kick in.
once the fan turns off you can turn the engine off.]