Coolant overflow empty

[mitchy]

when my car arrived the overflow bottle was empty and the coolant in the car was a light brown.. so i flushed it, and then filled it with water for a day, and then flushed it again and put in some coolant.

first thing i noticed was even after flushing it, it only took ~4 litres, with the bolt out of the thermostat, and didn't require any more even after running the engine.. i assume some was left in there from flushing, but what is the total capacity?

also, the overflow bottle always seems to be empty, but the radiator is always full. when i did the first flush, the bottle was half full, then was empty the next day, but the radiator was full.

and when i did the second flush, i check it 2 days later and the bottle was empty again, but the radiator is still full.

i cant see any signs of a split in the bottle either.

any idea's?

[Subaru ETA]

check the rad hose that goes to the thermostat housing for signs of leaking. this is what mine did

[miller]

Just noticed mines empty now, whats the best coolant to top up with? Or what does everyone recommend?


Mike

[Nick Mann]

Old question first - there is a drain plug in the block to release the fluid in the block. After draining and re-filling I have always had to top up a couple of times afterwards, I guess because there is always a bit of air in there somewhere.

New question - I don't know if it matters much, but as my temp needle climbs a bit on track, I have just thrown some of the stuff from Amsoil in - see if good coolant helps the temperature control.

[Paul Beazer]

I dont suppose your expansion tank has sprung a leak has it? Its not under pressure so it may just leak out by gravity.
Just a thought?

[Beastlee]

I can support the leaky top hose theory, it wasn't obvious as it was a pinhole on the bottom that only leaked under pressure. It also pours down onto the gearbox and pools so you dont notice it immediately, adding to the mystery.

I use a good quality branded anti-freeze (BP in this case) as a 50/50 mix with water (de-ionised if possible).

[miller]

Ive never ever seen my temp ever shift beyond half way, will top up and check for leaks over the course for this weekend.

Is BP a coolant readily available like Halfrauds? Never heard of it?

Mike

[Beastlee]

I bought my coolant from teh BP on camp. Makes me chuckle that all BPs in Europe are called ARRAL yet on camp they keep it as BP to save confusing everyone....