MINI heater problem

[jimmy156]

Morning all, looking for some thoughts/opinions in case there is an easy fix available for this.

Noticed today that my MINI's (2011 R56 Cooper S) heater isn't working properly. The engine is getting up to temp (i checked with the stupid app thing, how can MINI make a hot (warm) hatch without a bloody water temp gauge) but the blowers mostly blow cold. On the way home today (ambient around 16) i had the fans and temp set to HI and it would blow cold for a bit, the get warm for maybe 20 or 30 seconds, then cold again and repeat.

Thoughts?

[E-bmw]

It sounds like you may have an air lock & it needs bleeding.

[jimmy156]

E-bmw said:

It sounds like you may have an air lock & it needs bleeding.

Is that a case of just removing the lid on the expansion tank and letting the water pump do its thing? Or is there more to it than that?

[E-bmw]

FILL the expansion tank (engine cool obviously) to the top.

Put the heater on full hot & full fan.

Use the bleed screw on the front of the top hose to bleed any air out until you get just water out, top up as required to achieve this.

Leave it running for a while and check the heater output.

If you end up with the level a bit high and you can use a syringe to drop it to about 1" above "max cold", if not don't worry it will expel of its own accord when running, just expect a few drips from the overflow for the first proper drive.

Recheck level next day after it has cooled overnight & adjust as required.

Hopefully you will then have good heater output, let us know what happens.

[jimmy156]

Thanks for this...

Just had a quick look in the work car park and the expansion tank is pretty much empty! Oops! I checked it when I checked the oil about a week ago and it was fine. Perhaps if there is an air lock, it’s simply stopped it returning to the tank?!? Is Iy worth leaving the engine running with the cap off to see if any coolent comes around the system?

I will stick some water in and buy some coolent to chuck in at the garage down the road, and hopefully it’s not loosing it too quickly!

Bloody annoying that the MINI has no temp gauge!

[jimmy156]

An update

Stuck about 650 --> 750ml of tap water into the expansion tank and ran the car for 20 minutes with the cap off the expansion tank and with the blowers on hot (i had no coolant/antifreeze or tools at work and didn't want to run it with potentially nothing in the radiator as all i could see was a empty looking expansion tank. I didn't think this had worked, but once i screwed the cap back on and drove away, woop woop hot air!

So two things left to consider...

1. Have i diluted the existing coolant too much (serviced at the main dealer 3 months ago, so i am assuming the coolant was to spec to begin with) and if so, can i just top up with neat antifreeze (as i think it will be below the min level now) and let it mix itself by driving about.

2. I am assuming that i have a leak somewhere (although there is no evidence of one, i always park in the same spot at work) so need to get to the bottom of that

[E-bmw]

You say you are assuming you have a leak and yet you have had no signs of one, it could just be what seems to have ben an airlock.

What you need to do is to make sure in the morning with the engine cold you fill the expansion up to EXACTLY the max cold mark & then check it again when it is cold the next day as a starting point.

Obviously you can also be on the lookout for leaks meanwhile & the best way to do that is with it cold and a good torch to spend some time under the bonnet/car looking for any signs around all of the water system.

[jimmy156]

Well i topped it up with what i thought was all the antifreeze i had (some pre made-up stuff that i've had on the shelf in the shed for a long while) but when i was putting it back, after running the car around the block to mix it all, i noticed the concentrate bottle hidden behind some oil (at this point it was dark and i couldn't be bothered to go back to the car)

I didn't have enough to top it quite up to the minimum mark anyway, but didn't want to dilute it further as we had sub zero temps last night and didn't want to risk anything freezing. The up shot is, i should have some space to stick some concentrate in and then top up with some more water up to the max mark before work, and i will do as you say and check on it the following morning.

The reason why i assume a leak it that i must have put in over a litre of coolant/water now and it still isn't sitting on the minimum mark! The coolant must have gone somewhere.

Edited by jimmy156 on Tuesday 25th September 21:43

[E-bmw]

jimmy156 said:

The reason why i assume a leak it that i must have put in over a litre of coolant/water now and it still isn't sitting on the minimum mark! The coolant must have gone somewhere.

The reason I ask the question is right from the start of your thread there is no mention of you ever noticing that the level was correct, so do you know when it was correct?

[jimmy156]

E-bmw said:

jimmy156 said:

The reason why i assume a leak it that i must have put in over a litre of coolant/water now and it still isn't sitting on the minimum mark! The coolant must have gone somewhere.

The reason I ask the question is right from the start of your thread there is no mention of you ever noticing that the level was correct, so do you know when it was correct?

The car was serviced by MINI in July, so i am assuming it would have been correct then.

I also usually do a cursory check of the coolant bottle when i check the oil, which i last did a week or two ago. That being said, i could have forgotten to look / not noticed.

I have now put well over a litre, probably 1.5 litres of tap water and antifreeze, which seems more than would be necessary for a routine top up.

ETA: I will check again before i go home this evening and see where the line was. I topped up to the max mark this morning, so fingers crossed!

[E-bmw]

jimmy156 said:

E-bmw said:

jimmy156 said:

The reason why i assume a leak it that i must have put in over a litre of coolant/water now and it still isn't sitting on the minimum mark! The coolant must have gone somewhere.

The reason I ask the question is right from the start of your thread there is no mention of you ever noticing that the level was correct, so do you know when it was correct?

The car was serviced by MINI in July, so i am assuming it would have been correct then.

WOAH there! You are assuming a main dealer does everything they are supposed to.......... Mighty big assumption that!

[jimmy156]

E-bmw said:

WOAH there! You are assuming a main dealer does everything they are supposed to.......... Mighty big assumption that!

hence the italics!

I will go out and check at some point today and report back, it'll be dark when i go home so i will nip out at lunch or something.

[jimmy156]

So the level has dropped again, although not as significantly as before but still by a chunk (it was on the max mark and now 3cm below the min mark) and no obvious sign of a leak.

I will top up with tap water as i am at work and keep an eye on it tomorrow.

[TheBALDpuma]

jimmy156 said:

So the level has dropped again, although not as significantly as before but still by a chunk (it was on the max mark and now 3cm below the min mark) and no obvious sign of a leak.

I will top up with tap water as i am at work and keep an eye on it tomorrow.

Could be a hole in the top of a pipe do only coming out under pressure when driving?

Checked the oil to make sure it isn't going into the engine?

[Rockster]

jimmy156 said:

So the level has dropped again, although not as significantly as before but still by a chunk (it was on the max mark and now 3cm below the min mark) and no obvious sign of a leak.

I will top up with tap water as i am at work and keep an eye on it tomorrow.

Thankfully my Mini is coolant tight, but I had another car that lost a considerable amount of coolant enough the low coolant warning light came on and coolant tank level was low enough to require nearly a gallon of distilled water to top up. After about a month of driving the level was low again. After I topped it up as I did the time before I cleaned the tank threads and the cap threads and then made sure the cap was properly tightened down. There were no signs of any coolant leaks anywhere. I never even smelled anti-freeze which is a sure sign of a coolant leak.

I drove the car around town until the coolant was hot and the engine radiator fans came on low speed which happens when the coolant gets to 212F.

I shut off the engine and put a tent of foil over the coolant tank cap. After a few minutes I checked and water had condensed under the foil. There were no signs of leaks lower down -- the tank was quite full of hot coolant and no signs of any coolant were present.

I suspected the cap and replaced it. That was the source of the leak. The cap bleed pressure and water vapor when the engine was shut off hot. Over time this loss of water vapor lowered the coolant level. Since just water vapor was being lost in adding distilled water I did not dilute the anti-freeze/coolant mix of "50:50".

[GiveItSomeWellie]

jimmy156 said:

So the level has dropped again, although not as significantly as before but still by a chunk (it was on the max mark and now 3cm below the min mark) and no obvious sign of a leak.

I will top up with tap water as i am at work and keep an eye on it tomorrow.

Not an R56, but I had a water leak that was quite hard to trace on my R50 One just after the water pump had been changed.

There was a hairline crack in a 90 degree bend that joined between the water pump and the engine block. Not a common problem but it's one of those things, it did take some finding because the loss was so small and never seemed to hit the floor.

[jimmy156]

Thanks all,

On sunday it puked its guts completely and spilled most of its coolant, luckily i was on the way to the garage.

Needs a new thermostat and they are doing the aux belt and water pump fully at the same time.

Must have been leaking too slowly to notice originally and just suddenly gave up!

Thanks for all the help and advice all!

James