I had a coolant leak on my 09 MCS. The shop said it was coming from the thermostat and wanted $600 to fix. I wasn't paying that and just bought the part. This weekend I just installed a new thermostat housing/thermostat on my 09 MCS. I bled the coolant system using the instructions I found on the forum (below).

After the fix, I took the car for a cruise to see if everything is working okay. The cars coolant warning light came on. I went back and bled the system again. The heat is not getting warm, so I assume there is still air in the coolant. When I bled it was for about 5 minutes and I could see a pretty constant coolant stream.

How could I get more air out of the coolant system? I don't really want to take it to the shop to have them bleed it.

 

Your water pump could also be toast. Check the waterpump weep hole to see if coolant is coming out. If that looks good you probably still have air in the system. Supposedly the mini coolant system is a pain to bleed so the dealerships use vacuum bleeders and it still takes a while.

 

My mechanic confirms that Mini's can be tough to bleed. You might try putting the front end up on ramps or on an incline in your driveway, and repeat the process. Be sure to have the temp control on MAX hot Auto to get the flow through the heater core.

No hoses pinched at the thermostat, right? Oh, and does your model have an auxiliary water pump on the drivers side?

 

Check the water pump on the other side for leaks, once pressurized some people found there was a leak on the water pump side also. Also, check for leaks under the expansion tank, they can have hairlines cracks at the base.

Coolant Expansion Tank

http://www.ecstuning.com/Search/SiteSearch/17137823626/



Good to inspect. Takes a couple times to top off and get all the air out. Take a little led light and point it at the vent screw to see the fluid come out with the bubbles. The screw has to be almost backed out all the way it seams to bleed, at least when i did it, but watch so it does not come off so you don't lose it.

Good luck and I hope you can get it resolved.

 

Being in San Fran, you should be able to find a good hill to park on (sorry if that's a stereotype, not trying to irritate anyone). Park with the nose up, and let the car idle a bit. Observe if the coolant level in the expansion tank drops significantly. Let the car cool down and add coolant.

If you can't find a leak at the waterpump, the thermostat, or the coolant tank, it still may be trapped air. If the expansion tank runs low, it will likely suck air back into the system and you will need to re-bleed after filling the tank.

Good luck, you will get it.

Mike

 

I am worried that the water pump is done. I have a 09 and I think there was a recall on the water pumps, correct? It should have been replaced a while back. I will have to check with the Mini shop.

I made sure the hoses were okay after I reinstalled everything. I have an 09 S and from the videos I watch it looks like it is?


I was worried to back it out too much, probably hard to get it back in I don't see any coolant leaking when the car is running and the bleeder is closed. I will double check though.



There are very steep hills. Doesn't bother me, damn hippies with there Minis and VW vans I will look for more leaks, but didn't see any coolant dripping after I closed the bleeder.

 

"That's the auxiliary water pump that is located in front of the transmission. The main water pump is on the passenger side near that back of the engine. "

Additional Water Pump - aux water pump
http://www.ecstuning.com/Search/SiteSearch/11537630368/
"



"Ok, I was talking about when you fill the tank and bleed the air out to make sure the screw is almost all the way out so the sir comes out good. Give it another try and bleed again. "



"Yea in SF you should be able to find a hill. "


Here is a link to my thread with the Coolant / Thermostat housing / Waterpump check list and then link to the how to.

https://www.northamericanmotoring.co...8-no-heat.html

 

FYI from past experience w/ aluminum cylinder heads, once it over heats the head is warped therefore the headgasket is at high risk to fail. If i was you before going crazy get a LEAKDOWN test done.

 

Thanks for your help. I talked to a shop that fixes Minis and they suggest bleeding it again. Once it gets hot it forces air up. Since there is no heat coming out of the air vents it sounds like there is still air in the system. They said they use a tool to bleed the system. I will try again and see if it works. Made an appointment for Wednesday to have them bleed the system if I can't get it.


I was already worried about that.

 

Hopefully its not the headgasket and just air in your system. The heat has to blow HOT otherwise you have air in the system. Like mentioned above, put the car up on ramps while the front end is up put the heat to MAX and try to re-bleed it.

Good luck man

 

Update: I bled the system twice (5 min each) tonight with no luck. I could clearly see coolant flowing out. I sadly believe it is still air-locked. I am assuming there is air still in the system because the heater on high still does not get warm (blows coolish air). I made an appointment with the Mini shop to get them to bleed it. I am pretty sure the guy said they use a pressure tool or something. I will call to clarify tomorrow morning. To add to my theory, when I drove it around the block (slowly), I could see the water temp on my scangauge ii go up to 230F then back down to 215F.

 

Yea 230 is a bit high.. i think anything past 218 is in the danger zone...but since it goes up to 230 and back down to 215 means your thermostat is opening but as you said you have air in the system :(

 

Are these cars designed so that we cannot even change the coolant without going to the dealer;(

 

It really is sad...im going to attempt to flush my coolant this summer myself, hopefully it goes smooth

 

Update #2: The shop could fit me in today. They were going to drain the whole system and use a tool to suck the coolant through the whole system to remove any air.

The owner of the shop just called me to let me know that it is still over heating. He said there just is no flow in the coolant system. He believes that the thermostat is not opening and could be defective or it could be that the water pump fin/propeller broke off. The shop guy that it is at now looked at all the hoses and connectors any everything is correctly hooked up.

I bought the thermostat from the Mini dealership parts counter brand new (sealed box). Again, they wanted $600. I bought the part and I did the repair pretty easily last weekend (2 hour job). The car was running fine before I took it to the Mini dealership to get recall stuff fixed last week. It was just leaking a little coolant and I would just add more water/coolant for a temporary fix while getting to work. After the dealership it was running really hot (getting warnings). I figured it was just low of coolant and filled it up. It was still running hot and I just got it towed home covered under my insurance. I have been worried about the head gasket and warping the head. The temp before the dealer would sit around 220F and 225F at the highest. Hopefully something gets figured out.

EDIT: The dealership forgot to take the friction wheel out of maintenance mode. There is a spring that holds the water pump back from the belt.
http://parts.miniofsouthatlanta.com/...roduct=1271958

 

Incredible, that was a simple fix!

 

Glad you got it figured out. Oh and 220 degrees isn't uncommon at all for mini coolant temps. They seem to ruin fairly hot on purpose.

Sent from my DROID RAZR HD using NAMotoring

 

From what I have heard the JCW N18's run a little bit cooler.

 

I just had my thermostat replaced, it was running at 104deg Celsius prior, but after is running at 108.

I'm going to try and bleed the system, just wanted to know if the car should be ur. Ing when I bleed it, and how long do I leave the screw open and have the coolant run out?

Thanks

Dane (in Australia)

 

wow that was simple. If i was you I would go back to the dealer with this and show them that they forgot the friction wheel and that you want them to do a leakdown test on the engine for possible engine damage due to overheating because of their negligence.

 

Wow,

Great you figured it out. Would have thought it would have been done right. The friction wheel when you pull the little tab drops the bottom position of the wheel for installing a water pump or changing a belt. That tab has to be pushed all the way back in like in the photo.


http://www.ecstuning.com/Search/SiteSearch/11287598833/