I've got an airlock or head gasket gone

I changed my coolant the other day ready for winter and now the cars having problems.

Aside from the crazy misfire problem detailed in my other post. Every time i drive the car when i stop the coolant has all gone out of the expansion tank if i leave it a few hours and undo the cap i can hear bubbling and all the water comes bubbling back into the expansion tank.

I'm also losing water but not too much. I'm hoping this is just a small leak somewhere and not a blown HG. I've got no oil in water or water in oil.

Anyone got some advice how i can get rid of this airlock. I'm mega skint right now (saving for a new motorbike) so can't really afford to get the car in for a compression test.

thanks guys

sounds to me like a big air lock , did you completly drain your system to add the coolant ? , i have always with all my cars only emptied enough water to allow. the correct amount of coolant , if you did drain the system then it does sound like an air lock , i would just leave the car running with the filler cap off and just wait for all the air to exit , this may take some time (hours in some cases) and keep topping it up.

Try removing the highest positioned hose in the cooling system usually on the header tank of the radiator or the inlet manifold area of the engine, then top up the cooling system. Also check the bleed holes in the fixed pipe stubs are not blocked as well, sometimes you need to remove more than one pipe to bleed the system.

The trick is to remove the small pipe that goes from the top of the rad to the expansion bottle and blow through it to clear any coolant. This lets any air trapped escape to the header tank. You should get a steady stream of water from this pipe when it is upto tempreture.

yeah i blew through that pipe....only when i checked RAVE. I now get a steady stream of water out of it like you said. One thing i've noticed is the rad top pipe gets warm/hot really quick and according to RAVE this should only happen once thermostat is opn so i wonder if thermostat is stuck open but this wouldn't cause all my water to dissappear out of expansion tank would it?? I've got no steam out of exhausts so i'm starting to rule out Blown HG.

Thanks for replies

Mmmmm, I dont know ? What I do know though is that mine warms up really quick and runs with the needle just under half way regardless of conditions so must be working OK.

After driving it around all day doing most driving styles i got back and sure enough water gone from expansion tank. Left it 2 hours or so then went out and all the water is back so i'm sure its an airlock somewhere. This is the problem having LPG, because it uses the coolant system so theres more parts to get an airlock in.