does any one know how to get rid of an air lock in the coolant system of a k series engine/from a rover 1.8.

the prob i have is the engine temp guage was dropping to almost zero the blowers went cold, and when i popped the bonnet i noticed the water pipe going to the top of the block was piping hot and under pressure, and the pipe at the bottom (return to rad) was cold

I pumped the hot pipe, clearing the air lock temperally but it didnt fix it, Im also thinking the thermostat (even though brand nw or water pump may of failed.

any help would be appreciated.

Try filling it to the brim and leaving it for a bit.

Mine gets an air lock very easy, and you have to fill it as much as you can, leave it for 10 mins, and fill it up again until it stop going down

cheers joe, i'll give it a whirl.

if the problem persists take the stat out, also on the header tank is their a return? if so rev the car and you will notice the coolant move quicker. if so the pumps doing it's job.

Cheers phil.....Should i put the thermostat back in/do what with it, your didnt really explain it that well. also I assume when you say header tank you mean the resevior ?

yes i mean the resevoir, on some cars (well old renaults) they have a bleed screw on some pipes for air locks, check to see if their is any.

take the car off the header tank (resevoir) and rev the car to around 3k and listen for the water to circulate. If it does then your problem lies with the stat.

When you take the stat out check it in some boiling water. Also was the make QH?

I shall check them things tomoz, do you mean here though


"take the car off the header tank (resevoir) and rev the car to around 3k and listen for the water to circulate. If it does then your problem lies with the stat."

does, or doesnt

Running cold and no hot air could be the stat stuck open, though if it was stuck open it wouldnt pressurise a pipe as water / air can move round the engine. Try running it with blowers on hot, with the rad cap off - squeeze the water pipes and see if any air comes out of the rad.

If you take the stat out, drill a small hole in the housing - this will mean it can automatically bleed when you put it back together.

Is it using water? K series could easily be the head gasket....

cheers chew, just had the head done, so i have to eliminate that straight away.......

Could still be the head - once they go they can be very tempremental to get working right again if not done properly.

If its just been done take it back to where it was done and let them diagnose it

ok laaaaaa, tempted to just smash it in to a wall !

any way, i've bled it abit now, seems to be ok now, fingers crossed.craig from spray force done it, he's done quite a few of them so i can only assume he knows the correct procedure and all the little snaggs when it comes to the k-series.

why didnt they design n air lock free sytem like honda. Knobs

It's usually the horizontal pipes with bends in that make this hard! I've always cured it by giving each pipe a good minutes worth of squeezing. You'll see all the air come into the expansion tank. I changed my coolant today as well!!

Get a hose and stick it into the pipe from the radiator into the engine and take the pipe on the thermostat off. This is a good start to getting air traps out of the engine. You can also see if the pump is working by the swirly pattern the water comes out at.

cheers bud, I aint got a clue what your goin on about, but it was useful lol