Thread: another OAT coolant brand

Originally Posted by DEFENDERZOOK

dont use premix to replace your coolant.....you cant drain all the water out from the cooling system.....
so if you refill with premix.....it will be too diluted......

you will only manage to pour in about 5 or 6 litres out of a possible 13.5 or so......

Checked today and found I can only get 20L or 205L drums of premix

So that's it, I'll just have to make do

Originally Posted by ladas

Okay so if you can only get premix, drain what you can from the system.

Run clean water through the system until the water leaving the drain is clean/clear water, leave this flushing for 15 mins.

Disconnect the heater hoses.

Drain what you can from the heater.

Reconnect one of the heater hoses. Put the cap back on the overflow/expansion tank, replace the air bleed cap - if fitted , leave the drain open, then blow compressed air down the other heater hose, in the direction of the heater, until all the water is out of the drain.

You should get a further 6 - 7 ltrs of water out.

With it all out, reconnect the heater hose, remove the cap off the exp/overflow tank, replace the drain tap/cap/hose. remove the bleed screw, then very slowly add the coolant, take you time, this almost eliminates the chance of airlocks. Put a ltr in, then wait, then another.

When full, pop the bleed screw back in, not tight, run engine, carefully remove bleed, adding addtional water until no more air comes from the bleed screw.

Sounds awfully like the Workshop manual instuctions ( not quite - there's nothing about raising the overflow tank and hopping on one foot).

That's about what I was going to do and then I was also thinking of another drain and refill. Then after a short run of the engine (with the heater on), that should mix out any additional coolant and then I can drain and refill and be pretty much full of the one premix concentration.