HELP - Bleeding the 318is cooling system

[martinclan]

I am replacing the O rings on the heater feed pipes in my 318is which means draining the cooling system. Does anyone know how the 318is cooling system should be bled after it has been refilled. I can't see any obvious bleed screws - in fact at the moment I can't even find the thermostat housing - it seems to be buried somewhere in the engine....

[Martinaston]

On the m40 engine the bleed screw is on the top of the expansion tank that is part of the radiator.
As for the m42 block i don't know what the rad is/looks like.
Any help?

[320Touring]

the bleed screw is located at the expansion tank on the radiator-should be a large phillips type plastic screw

see the pic below for a guide to where it is...



hope that helps?!

[Martinaston]

Check this one. Part 8 on the list, if you have that rad.
http://www.realoem.com/bmw/showparts.do ... g=17&fg=05

[320Touring]

Check this one. Part 8 on the list, if you have that rad.
http://www.realoem.com/bmw/showparts.do ... g=17&fg=05

thats the one! top job martinaston

[martinclan]

I would never have thought for looking for bleed screw on the expansion tank! - cheers Martin Aston

Robin

[Geeman]

Yup... deffo on top of the expansion tank, though you didn't need me to tell you that now...

[Martinaston]

The best thing to do is bleed it three time at least.
After the first time run it for five min's or so then bleed again.
Then take it for a run and get the revs up, then bleed again.
They can get quite a big air lock in them and if the water level in the expansion tank get's all the way to the bottom it draws the air back in and over pressurises the system, then everything goes pop.