I replaced my leaking thermostats today with new gaskets and housings
also I refilled it up with a bit of valvoline zerex(?) coolant

however, i have seen some threads that i have to purge the air out of the radiator. Well, i saw two valves with caps on, near the radiator. When i push on the nipples, alot of air gushes out... (not sure if i am doing it right tho.. lol)

so,,,, how would one purge air out of the system?
please walk me thru!
thank you in advance.!

 

The valves you pushed, did they have black plastic caps on them? If so, those are for the A/C.

There are no valves/bleeders on the radiator itself.

Do you have a Cooper or a Cooper S?

 

Oooooooooooo yeah there were two with black caps;
oops

Yeah, i have MCS, how would u purge the air out then?

 

Time to take a trip to the local auto store and get more A/C refrigerent. Might want to pick up the gauges too, they are handy to have. How long did you push them? You hand had to get cold from the gas being forced out.

 

I wish you posted MCS at first, I had a whole post with illustrations ready to go, but didn't know what model you had.

Anyway,
There is a bleed screw on the hose that runs in front of the intake manifold...
Number 5 in this illustration...


There is another bleed screw in the pipe next to the thermostat housing that runs along the side of the head...
Number 2 in this illustration...


I'm leaving work now, if no one chimes in when between now and when I log back in later, i'll go through the bleed process then.

 

Not for long ! A few secs at the max (figured that it could be A/C) haha


I am looking forward to that!!!
O yeah, btw, what are the symptoms of air being trapped in the system?

 

Fill the expansion tank to the proper level, and leave the cap off.

Remove the front bleed screw(the one in front of the intake manifold) and fill the hole with coolant.
Put the bleed screw back in, be careful not to over tighten it, because it's only plastic.

Start the engine, and let it warm up a little.
Make sure the coolant tank stays full while the engine is running.
Put the expansion tank cap on.

Locate the secondary bleed screw(the one next to the thermostat). You can reach it with a 1/4" drive ratchet, long extension and a 8mm(?) socket.
Just loosen it, do not remove it and watch for air coming out around it.
Tighten it back up, and go to the front bleeder and do the same thing.

You will have to go back and forth to each bleeder a few times(maybe more) to get all the air out.
You also may have to let the car run for a few minutes with everything closed and hot to give the air some time to rise.
This process works for me.

Good luck.

 

You may have reduced heat output...
You may hear some sloshing inside the car coming from the passenger foot well area...
If there is a lot of air in there, you may see higher operating temps due to lack of coolant circulation.

 

O man Partsman, THANK YOU SO MUCH. I will purge it tomorrow!!!!! Ommmmm

Thank you again!

 

You're welcome, glad I could help.

Check the coolant level in a day or two after normal driving, and after the car has sat overnight.

 

On subject of bleeding coolant, what is the recommend type and mix of coolant for the Mini?

 

Yeah, aside from juicing some Smurfs, does anyone have a line on the blue stuff?

 

I will change the radiator in a day or two also and I was wondering if these bleed screws are the same in MC (2004)...

thx