Morning. Love the site, first post here.
03Mini. Wife's car to drive to/from work. 75-80 mi/day.
145,000 miles on it.
We seem to have been having a slight coolant drip somewhere, where the xtra coolant resivoir would empty out over time... like 2 months of time. If another month or 2 would go by, we would have to add a small amount of coolant to the system. So, there is a miniscule drip somewhere... Think we may have found it, as one of the main rad. hoses had some spew on it, top passenger corner, and replaced the hose. No big deal.
To be on the safe side, someone mentioned to my wife to add some radiator stop leak. I think this may have plugged some of the heater core... And now, when it is 25deg f outside here in ct, there is almost no heat at all. (id say about 40-45deg heat coming from the vents.
Opened the hood last night, finally found the super short heater hoses to the firewall, and the inlet is nice n toasty hot, and the outlet is frigid cold, but on the outlet side, after the 'plastic' connection piece, is nice n hot again from the block. So, i am assuming there is a plug up in there, if not at the connector (coupling) piece.
I also purchased a new thermostat if needed, but am unsure if replacing that is necessary.
Any suggestions on back-flushing the heater core? I will have the vehicle all this upcoming week, and can tear it apart as much as needed. I know there is a plug somewhere and cant have her driving in freezing temps. Id bring it in, but we are holding out till the economy gets a little better, to just trade it in for a new one.

Thanks for any help guys!

 

You can try flushing it...sounds like you should get fresh coolant into the system anyway.
There is no "drain plug" in the mini...you need to remove the lower rad hose+the heater core hoses to drain the system...
You might be able to "blow out" the heater core with some water from a hose....
When done, simply reconnect the hoses, refil, and bleed. The bleeding is tough...but when it is mostly done, some driving might help..
One thing..have you rebleed it since you put the hose on? You might have a air bubble in the heater core if you are lucky.

 

Thanks for the response.
Yeah, think mini flushed it like 2 years ago... for like 700 bucks........
ANYWAYS.. lol...

I havent taken the hoses off yet, she needed the car, so i left it be, so dont think its an airbubble at the moment... unfortunately... Yeah, bleeding will be a ***** i think, the seemingly split system here... interesting how its all done... And so different from us cars.

 

Ouch!! $700!!
Takes about 15$ in coolant, and about 1hour...maybe a couple extra to get it right the first time. Hope they did a few other things too for the $$. Good luck!!

 

Thx bro.
No... nothing else to my knowledge... She brought it in cause they sent her a card saying it was time to bring it in, and they told her she needed a flush.... and that was that...

ANYWAYS...

lol...


Planning on pounding it out this weekend. Hope it warms up here a lil. Sheesh.

 

So, update...
Flushed the core, kinda a pain in the rear... Replaced the thermostat at the same time, boy these guys like zip-tying everything to everything under there dont they?... And now have heat! The additive she put in there turned into a glue like substance, and took me 3 or 4 short trips around the block to get all the air out of the core, but heat is good now, and the aux fan doesnt kick in any longer.
:-)

 

I have a '02 MCS.. heater problems as well.. Do you remember, or did you find a DIY heater core flush instructional online?