Thread: Airlock TD5 radiator

Originally Posted by crump

got the email thanks Ladas, yeh the Fender procedure is different, the bottle is mounted higher then the bleed screw already.But that still dont answer the question, how do i get all the coolant out?? If I blow it with air wont I then definitely get an airlock when I refill?

No you won't.

If you have drained the system fully - what has replaced the fluid - yep air, so introducing at one end under pressure, with the other end open - will remove any water, and that's it. When you stop pumping air through - the air in the vacant space will just return, very quickly to normal.
, plus as said, I do prefer to undo the heater hoses, you don't really need to but the bottom of the heater matrix on most vehicle is very low, and the pipes go through the firewall at a higher level

Remove the bleed plug, and add the coolant slowly, take your time.

Will have to have a crack at this myself cos i'm in the same boat as crump, it just don't make any sense where the coolant is hiding.

ok, so i do it again, if I put a 40l compressor hose in the ex tank at low pressure is that enuff to blow it out?

Originally Posted by crump

ok, so i do it again, if I put a 40l compressor hose in the ex tank at low pressure is that enuff to blow it out?

Dunno about about putting the hose in the expansion tank - unless you can seal off the cap hole in the top of the tank sufficiently.

You can push the air through the bleed hole, or the small overflow pipe from the ex tank to the top of the rad. Or one of the heater hoses.

But only have one exit point open, preferably the lowest point, which I think is the bottom rad hose. - this will ensure the air will push through the whole system removing any water, make sure, if you have one, that the heater valve is open.

Low pressure 20 - 30 psi is good.

hey...youve done the job......you flushed it out with clean water......you put the coolant in.......you started it.....and drove it....and it didnt overheat.....

let it cool and check the level again.......

when its at operating temp.......open the bleed screw slightly and carefully....if there is any air it will escape through there......


just keep your eye on the temp guage for the next day or two as you drive.....and recheck the level when it has cooled......

Still worth while disconnecting the heater hoses under the bonnet and blowing that seperately

Originally Posted by PLR

G`day Steve

I could be wrong but it doesn`t sound to me like you`ve drained the block ?

If you didn`t undo the block drain plugs you haven`t got all the coolant out .

If you`ve flushed it with water and haven`t drained the block , what coolant is left in the block after mixing with the water is diluted .

Even with the new coolant at the correct mix because what is still in the block is diluted so will your new coolant mix be .

If you want the correct mix of coolant the easiest way would be to drain the entire system again .

Fill it the way you have , knowing the quantity it holds and how much it takes .

If you get the correct amount into it you don`t have to worry about air locks .

You`d be surprised how many people don`t have the smarts and/or knowledge to go about it the way you have .

They are unaware of any problem untill the damage is done .

Cheers

I don't think Defenders have drains on the block - or TD5 Disco's either

I'm gonna drill one and plug it with the connector off the injector harness.