hey everyone,

my mini is doing something weird. It is currently sitting and not drivable. There are a few symptoms. The water in the overflow is boiling. The temperature will stay on the middle mark for a while and then all of a sudden it will spike to the red. I assumed thermostat by the way it was asking. I replaced the thermostat today and it didn't fix it. it does the same thing. I'm wondering if it is still a thermostat or something else. I put new antifreeze. Any ideas? Any help with be nice. I need my car running asap.

 

Did you bleed the system? Maybe you have some air in it.

 

Could be the water pump. You need to see if it is circulating.

 

I'm not sure if it is circulating or not. I tried to bleed the system via the bleeder screw next to the fan on the radiator hose. I never got any antifreeze. Just steam. I'm thinking the water pump. When I fill the expansion tank to the line, turn the car on, let it run for a minute, the water will disappear as if the thermostat opened but then when you refill it just a little the water start boiling out and spewing out of the expansion tank. thats why i thought the thermostat was bad.

 

I would suggest you leave the cap off when it is cold and start it. Then wait to see if the thermostat is working and if the WP is circulating. If you are getting steam and not coolant, you still have air in it.
Maybe this will help
http://www.pelicanparts.com/techarti...ant_Change.htm

 

Check your Pump & Fan.

 

And open BOTH bleed valves.....

 

The other bleeder is hard to find and requires a flashlight to see. I think it is an 8mm head and requires about 6" of extension to reach. It is to the right of the valve cover and down alongside the engine block.

 

Ya, it's hard to find. I snapped a photo when I finally found the other bleed screw. It's here:
https://www.northamericanmotoring.co...6048&styleid=8

 

well i bled the system and it didn't work. I started the car. Let it run. I kept having to refill the overflow. i got water out of both ports at the same time and closed the ports. let the car run for a few minutes and it started spewing all the water i had added and i had to turn the car off. Any ideas? i still think the thermostat is hanging even though its a new one

 

Are you sure the thermostat is installed the right way? Quite a few have been installed backwards...

 

I thought it could only go in one way

 

Guys I really need your help. I seriously need my car running. I have no other transportation as of this Tuesday. Can anyone help?

 

Is it overheating, or overflowing? If it begins to overflow somewhere between 180 - 200 degrees, it's just the thermostat opening, and you might have overfilled it a little. If you're getting to over 215 - 220f, yes that's overheating. In your test menu you can display a temp guage in place of your odometer. It's menu 19, then sub menu 7, -Instructions are in the sticky on the forum about how to do a computer reset (which is submenu 21). Just follow that but choose number 7 instead. It will be in Celsius not Farenheit.

When I filled and bled mine, as the car warmed up (with the cap off) I kept seeing the coolant disappear from the resviour. I kept adding a little more. Btw the heater in the car should be on high heat, fan low when doing this.

Also, as the car is warming up, you'll see the small hose on the top/side of the resviour is spraying coolant into the bottle (indicating the water pump is working)

So as the system is bled, closed the valves, adding more coolant as needed, I was adding as needed trying to keep the bottle about half full. I had not needed to add any for a while, Then I noticed the resviour bottle was nearly all the way full and rising! I put the cap on.

Over the next couple days, a little bit of coolant would leak through the pressure cap. That's just because I overfilled it a little. I cleaned it up, and it stopped doing that. When it's cold, the resviour sits at only about 1/4 or 1/3 full -it needs the rest on the volume of the bottle for expansion when it gets warm.


Other things:

Is new thermostat installed the right way?

Does your cap hold pressure?

Does your resviour leak at the seams?
Any leaks anywhere? Hoses, water pump, or thermostat housing?

What's your engine oil look like?

Does your fan work?

Edit: I guess the stock 195 thermostat doesnt begin to open till 192, I thought it was a little lower temp at which it might begin to overflow if overfilled

 

Looking at your first post, you said changing the thermostat did not change the behavior....
So a few questions..is the cooling fan running?
Next, check your oil...look OK?
Any change in the way the car sounds over the last few weeks? Any sound of kinda clanking chains?
Any idea if the cooling system has been matained? Drain/fill or flushes every 36-48 months?

 

R53 Cooling System:
For 2002-2006 R50 MINI Cooper and R53 Coooper S Hardtops, and 2005-2008 R52 MINI Cooper and Cooper S Convertibles.
Thermostat
Thermostat begins to open at 89-92° C (192° F - 198° F) and is fully open at 103° C (217° F).
Expansion Tank Cap Cap pressurizes the system to 1.1 bar (16 psi) at which point the cap valve will lift to relieve pressure.
Cooling Fan
Radiator Fan is a nine bladed fan measuring 400mm in diameter, driven by a 350 watt motor controlled by the EMS2000.
Low speed is switched on at 105°C (221° F) coolant temp and off when the temperature drops to 101°C (214° F).
High speed is switched on at 112° C (234° F) and remains on until the system coolant temperature drops by 4° C (7.2° F) at which point the system will revert to Low Speed.
The cooling fan will also operate on Low Speed when the Air Conditioning is switched on and system pressure reaches 8 bar (116 psi). Should the Air Conditioning system pressure rise to 18 bar (261 psi), the fan will automatically run on the High Speed.
Bypassing the Resistor:
1. Unplug 3wire harness
2. Connect brown of socket>black wire's pin
3. Connect thin red/green of engine socket>fan's thick red
Get hi @ lo-speed but nothing when hi is supposed to kick in

 

I have an update. I bled the system again and kept adding water . I kept bleeding til I didn't get anymore water out if any port, which I thought was weird, but I closed all the ports. Put the cap on the overflow and let it idle for a bit. It never once got hot but the water in the overflow was still boiling/ bubbling. I know that the water pump is working bc that little tube is spraying. So now I think the question is why is it all of a sudden backing up and boiling? Also water started coming from the threads of the cap. I wonder if the cap would effect it that much if it were bad?

 

Pressure keeps it from boiling. Recall Boyles & Charles Laws.
Is your fan working? Check by turning A/C on, fan should kick in. If no hi & low, check fan motor. If you've hi & no low, you may bypass the toasted resistor.
Is your coolant tank split on the seams? The Canton or RMW tanks w/ real pressure caps are the best replacements around.
Don't rely on the temp gauge. A scangaugeII would give you coolant temp readings accurately.

 

Did you mean just water or 50/50 coolant mix? Destilled water and coolant

 

Anti-freeze does just as it says: lowers freezing point & elevates the boiling point of the mix.....but distilled water has better heat dissipation.
Here's another lifetime option: WATERLESS COOLANT
http://www.evanscooling.com/products/coolants/

 

Yes I used 50/50 mix.

 

Yes my fans are working too

 

At this point I just wish I had someone who lived In Chattanooga who could fix it. I have to have a car bow

 

Hate to say it...
But the boiling might be as much a symptom as the issue....
Guessing a bad water pump maybe or a blown head gasket....
Might be time for a tow and a shop.

 

This might be coming from left field but I have seen on several Mini's this issue when the crank damper is going south.