MiniTorque.com banner

1 - 20 of 72 Posts

·
Registered
Joined
·
78 Posts
Discussion Starter #1
hi guys just a quick first post.

in the title really if any of those problems occur i can help as ive just fixed my issues :)

basically after a run in the mini on a weekend sometimes my coolant will boil over in the expansion tank and i thought it was because of an airlock. i bled the system for a year now about 5-6 times as it happened every time. so while researching and looking through many mini forums it came that i needed to do a very long run and needed to sort this coolant boiling over. so after many days and nights 3 to be exact i found a very long northamerica mini thread.

basically the coolant over boils because it is not being cooled by the radiator which means the fan isnt working. however all minis have 1 fan but 2 speed modes low and high. when i switch the car off usually the high fan speed is kicked in due to preventing the car from blowing up..

anyways the low speed fan setting is controlled by a resistor which gets knackered and wears out. apparently a lot of minis the r50 and r53's many people have never herd there low speed fan just high speed.

but there is a simple fix if you know your fan works i.e high speed fan kicks in.

the fix has 2 options:

1. by pass the resistor so when the low speed fan is supposed to come on the high speed fan comes on instead. i have done this mod and prefer it due to the fact that better cooled the car is better for the engine and increased performance.

2. a new resistor can be installed to allow the low fan speed to come on when needed working like factory.

please note there is 2 different ways of by passing and wiring in a new resistor. the difference will be in which type of fan you have. usually 2003 and before has the 2 plug fan which i have and after 2003 usually has 1 plug. meaning if you have 2 plugs fan needs to be removed or if you have 1 plug you dont need to remove the fan.

but since i fixed my fan issue the coolant has been perfect no loss or over boiling. went to london 3 times in 2 weeks and was perfect no over heating no over boiling coolant in expansion tank and no loss of coolant :))))

any question please feel free to ask and will help you as much as possible and will include some pics not all... :)

thanks for looking and hope this helps :)
 

·
Wineeeeeeeeeeeee
Joined
·
2,286 Posts
What temps to they kick in I was dat in London traffic today and intake was 55c and water was 105c, I have never herd any fans come on in the 3 years I've owned it :(
 

·
Registered
Joined
·
8,732 Posts
You might have bigger things to worry about if your coolant has boiled on many occasions.

I could be wrong but I think low speed comes on at 106 and high speed 110. When you're sat in traffic for an extended length of time it helps to whack the heater on full and open the windows. Helps to draw off some heat from the cooling system.
 

·
Premium Member
Joined
·
10,034 Posts
Ian your low speed fan is probably goosed. I didn't even know I had one, let alone it was knackered till I had a temperature gauge based fright. If you've got a scanguage you should find the low speed kicks in at 105c and the high at 112. If you haven't you can go into the menu on the centre speedo display and view the coolant temperature from there
 

·
Registered
Joined
·
2,448 Posts
Hijacking this thread...

Jacked up my car last week on the right hand side, when it got to the height where the front left wheel was off the ground, every drop of my engine coolant decided to piss out around the sump area. Guessing its a busted pipe so are they easy to access and change?

But like the OP mine always boils over, and I can see steam at traffic lights etc after being on a run (latest southern hoon will know what I'm talking about). Busted expansion tank & cap or fucked coolant system in general? Have to top it up once a week
 

·
Premium Member
Joined
·
10,034 Posts
The bottom hose is a bumper off job but you can do it with very basic tools. Is the steam only when its raining? If it is then it could just be water on a hot intercooler. Check the seam and cap on your expansion tank for crusty deposits which'd indicate a failure
 

·
Premium Member
Joined
·
10,034 Posts
sounds very much like a faulty expansion tank or cap. I can be difficult to spot if its round the back. If it is starting to split and youre tempted by replacing an OEM item avoid second hand ones off ebay don't, they are stupid money and can be had new from the main dealers for the same money (forty quid ish plus vat for the tank iirc)
 

·
Wineeeeeeeeeeeee
Joined
·
2,286 Posts
Buy an Rmw one Ben with over flow hose, since then I've not coated the engine in coolant coolant, only went up to 105 today as I wasn't siting for to long, next time ill pop the hood and see if its on as I couldn't hear anything
 

·
Premium Member
Joined
·
10,034 Posts
If you're at temperature and you turn your air con on in a couple of secs the fan will come on at full chat. Slow speed which should come on at 105 shouldn't sound any where near as noisy. From memory I think slow speed should stay on till the temp has dropped back below 100c but I could be wrong
 

·
Registered
Joined
·
78 Posts
Discussion Starter #12
i think your whole fan unit has gone low and high which needs a new fan. but you can test to see if your fan works at all. put your a/c on and your fan shud come one every 1min or about there, if it does come on, means your low speed is a goner and you need to do what i said or else you will be having that boiling over and loss of coolant problem.
What temps to they kick in I was dat in London traffic today and intake was 55c and water was 105c, I have never herd any fans come on in the 3 years I've owned it :(
 

·
Registered
Joined
·
78 Posts
Discussion Starter #13
i can gurantee your its your low speed fan that is not working if it boils over after a run. simple fix really like i mentioned. and when you jacked up the car was it hot or cold? could just be the over boiled coolant that has boiled over and just sat puddled in the gearbox or other crevices... could also be the thermosta hosuing which can crack i relaced mine the other day when i flushed the coolant and fixed the fan only £50 from mini that is with the thermostat included as well.
Hijacking this thread...

Jacked up my car last week on the right hand side, when it got to the height where the front left wheel was off the ground, every drop of my engine coolant decided to piss out around the sump area. Guessing its a busted pipe so are they easy to access and change?

But like the OP mine always boils over, and I can see steam at traffic lights etc after being on a run (latest southern hoon will know what I'm talking about). Busted expansion tank & cap or fucked coolant system in general? Have to top it up once a week
 

·
Registered
Joined
·
146 Posts
interesting thread, my coolant drops suddenly will look into long car/ trips as i normally only use it for work (10 min drive) but alot longer on a sunday
 

·
Registered
Joined
·
8,800 Posts
Thermostat, head gasket, knackered fan fuses.

All 3 of those could of killed my R50 as they all went together at the same time.

Check your oil for the mayo of doom
 

·
Registered
Joined
·
2,448 Posts
Thermostat, head gasket, knackered fan fuses.

All 3 of those could of killed my R50 as they all went together at the same time.

Check your oil for the mayo of doom
Its nothing head gasket related for me, just a busted pipe and knackered tank.


Thanks for the advice, I'll look into the RMW tank but guessing they are quite pricey!

When I got the car almost a year ago the whole coolant system was knackered, wouldn't hold coolant for more than a 15 minute drive. Radseal I think it was had stopped the problems until now so for a short term fix it did pretty well
 

·
Registered
Joined
·
8,800 Posts
Its nothing head gasket related for me, just a busted pipe and knackered tank.


Thanks for the advice, I'll look into the RMW tank but guessing they are quite pricey!

When I got the car almost a year ago the whole coolant system was knackered, wouldn't hold coolant for more than a 15 minute drive. Radseal I think it was had stopped the problems until now so for a short term fix it did pretty well
Rad seal is a cunt. It lasted me 3 days before making one of my pipes explode and chuck coolant all over the engine. Thought the whole car was gonna blow as steam went EVERYWHERE.

Parked up, put some water in, had a smoke and waited for it to cool down while everyone on the A12 looked at me while I wept... :lol:
 

·
Registered
Joined
·
3,198 Posts
" Radseal I think it was had stopped the problems until now so for a short term fix it did pretty well"
Radseal will now cause a whole lot of extra problems .....
The Mini cooling system is a crock of shit , it's poorly designed , look up boiling point of water vs pressure , then look at the margin at 112 degrees c at cap pressure .
The caps on the header tank are plastic crap , years ago I posted on testing new caps they varied on blow off pressure - the RMW tank and cap would as a minimum give you a constant pressure in the system .
All quality cooling systems have fast warm up and constant temperature , regardless of use , the mini has stat temp and then 105 and then 112 - right there you have non constant temps , to cover this fundamental flaw BMW gave you a gauge that don't move from normal right up to the point you boil your engine , they might as well have glued the pointer at N - lol
- you don't even know if the low speed fan has failed !
 

·
Registered
Joined
·
8,800 Posts
Sounds like radseal may have fucked me over then. Well it was all fucked before so i lasted an extra 10 months I guess, better than having to fix it back then
Gotta pay good money to maintain a good car man. Hobo fucks you hard and doesn't cuddle after :lol:
 
1 - 20 of 72 Posts
Top