44 replies to this topic

[Chris M]

Hi Romblu89 no problem as that’s exactly what mini is doing. I’ve fitted 2 new caps now & still the same. 1 cap came from euro car parts & the other from mini sport.
I’m thinking of fitted a bmw mini cap as I’ve heard that they are better. Does anyone know what year etc bmw mini cap is suitable?

[romblu89]

This is the one I’m using.. https://www.amazon.de/dp/B00HTZ9RWQ

[Chris M]

That looks exactly the same as the one I bought. Has it fixed your issue?

[romblu89]

No but it was leaking through the cap before while it was boiling now with this cap and a new bottle its not. The difference in the cap is that it seems to have more thread count that the other caps. My old one had two, this one has 3.

Edited by romblu89, 22 July 2019 - 08:50 PM.

[Chris M]

Tonight I fitted a cap from my wife’s 2017 mini & made no difference. I then put some PTFE tape around the cap thread on the expansion bottle, ran until hot, started to bubble then the fan cut in . I let it run through this cycle a few times & seems ok.

[Kubbar]

Hello

 

the boiling over in MPIin a lot or reasons: 

 

1) check the water pump 

2) fan work fine ( some time the fan speed is less than the normal the issue with the motor)

3) head cylinder gasket 

4) the thermostat ( maybe you have a high temp. in hot country we use 74 c)

5) check all hose no leak

6) expansion cap ( air come out)

7) temp sensor the brown ( some times not get from the ecu)

8) the radiator closed inside need flushing

 

and so many check all the above 

 

 

thanks 

[Chris M]

After testing, checking & replacing parts I can finally report that I have fixed it. I have fitted a new expansion bottle & cap. No more boiling & bubbling ? so obviously the tank wasn’t holding pressure.
Now I can start to enjoy the car again ?

[gronkjor]

I had a cooling issue last summer whilst driving in the alps. My expansion tank was boiling whenever the car got warm. After replacing the cap and expansion tank the boiling issue is gone. That said when really hot the water is still bubbling back into the expansion tank when I turn off the engine. It doesn't seem to loose any water. 

[Quinlan minor]

I've suffered similar problems, on mine.

Once it was a split in the header tank seam, next to the wing where you couldn't easily see it. The most recent time, I'd tried new caps without completely solving the problem, until I got one of the blue seal BMW ones, instead of the cheap and nasty internet ones.

Solved the problem completely.

Edited by Quinlan minor, 25 December 2019 - 10:35 AM.

[tom1]

I have just developed a over heating problem(my mini).I have used a inferred temp gauge to take some readings. The temp along the top hose, goes down from high 80's at the thermostat end, down to 20's where it goes into the rad. Mid 20's across the rad and high teens on the bottom hose. The top hose also gets very solid/pressurized. What would you think about this ? 

[Quinlan minor]

Sounds like a flow issue.

Blocked rad would be my first check: remove it and flush it with a hosepipe.

[tom1]

That was my thinking. I have flushed it out in place but it is still over heating 

[Quinlan minor]

Next, you could check the thermostat is opening fully but, to be honest, it's simpler and inexpensive to replace it.

Do you know how old the water pump is?

Edited by Quinlan minor, 16 January 2020 - 08:07 AM.

[tom1]

Was thinking of taking it out for a short time test. I have got a thermostat for it on the shelf,as a few years back I had the feeling it was sticking open as it tuck so long to warm up. Oh how things have changed. Unsure on the age of the water pump. Would need to look at it in day light. I have had so many minis over the year they all start to blend it one.

[Quinlan minor]

I've only ever had thermostats stick shut on Minis, Tom, the worst option!

Heater on full, fan on full and sweat it out all the way home.

One eye on the temperature gauge. the other on the road.