Ok its done.The full and proper way
Got 5 ltr readymix OAT (red) from halfords and a new hose clip, and just as I expected the old clip was rusted solid,as it was a wire one I was able to bend it off.
But first had to remove undertray 1 bolt solid so left it another one ok and 3 plastic clips, past experiance with these is that thy snap so already got some new ones ready.
As 1 bolt was stuck i just bent the tray out the way.
The bottom of the rad was plastic.
I then followed this guide --
- -wait for system to cool till luke warm
-turn heater to hot to open the heater matrix valve
-remove rad cap
-remove front undertray below radiator if fitted
-jacking the front up may help access if suspensions been lowered alot but most cases its not needed
-place container under radiator
-loosen and disconnect lower coolant pipe from radiator, drain all coolant into tray. syphon coolant out of the expansion tank if you can be bothered but its not important
-reconnect lower pipe onto radiator, replace the clamp if too rusty
-mix 50/50 coolant/water in a bucket or ratioed to the season
-fill expansion tank to full
-slowly pour new coolant into the rad till its full then help purge out the bubbles by squeezing away at the top coolant pipe till no more bubbles emerge
-remove air from the expansion tank u-pipe (squeeze top pipe, cover rad port with palm, release top pipe to suck air/coolant through the pipe, repeat 3x and topup tank if needed)
-leave rad cap off and heater on hot
-start engine and either let it idle (takes longer to warm up) or rev to 2k till the fan has turned on & off. this allows the thermostat to open at 82c letting any bubbles out before the fan kicks in
-while warming up, the coolant level at the rad port will begin to expand too high. simply cover the rad port with palm, squeeze the top pipe to push the excess into the tank, remove palm and release top pipe
-turn engine off, fit rad cap, turn heater to cold, let engine cool down and check the coolant level
if the coolant was dirty, the remaining coolant in the engine and radiator will need flushing with a garden hose
perfect except did not touch the block, the bit about palm and squeezing the top hose was a very good trick.
I took out 3.5 ltrs and put back 4 as the tank was at the lower mark at the start and it is now at max. So I think that just about all of the old coolant comes out with out draining the block - if you can even do that. I did take out the old coolant from the tank with a sryinge and rinsed with water and also rinsed the rad, just chucked 4 ltrs of water down it.
I was carfull not to over tighten the new jublie clip as I know you can cut into the pipe.
So fingers crossed lets see.