Stumped By Coolant Issue.

[Green-Chameleon]

Hello

I'm a new member so greetings and thank you in advance for any help.

My son has a Mini Cooper 54 reg and recently had coolant issues;

First of all the fan kept coming on loud so assume it went straight to speed 2 - Once or twice this continued once the engine was switched off.

Then we found the water level to be low so topped up and ran it, fan still on constant as soon as engine started.

Water leak on radiator was discovered so we added rad weld stuff for quick fix until fan issue sorted then new rad will be fitted.

I have replaced the thermostat, checked all fuses and checked the temp sensor on passenger side of head next to the thermostat and swapped fan relays around inside and under bonnet.

The sensor ranges on a volt meter are 8.44 when cold and drops to 1.95 when dropped in hot water so that's moving. With the sensor back in and engine running I unplugged the sensor but the fan continues to run and temp gauge shoots up to red - fan continues.

Placed snap on code reader no faults logged checked engine temp was at 82 yesterday after engine ran for 10 mins and never overheated - placed it on this morning engine cold showing 21 engine temp fan kicked in as soon as started temp still on 21

Looked tirelessly on various forums at posts on fan resistor but haven't found anything that relates to this issue all seem to say fan continues to run once car switched off.

Would be very grateful for any help and insight.

[Green-Chameleon]

Also, if anyone could let me know at what temperature the 1st stage and second stage fans are supposed to kick in, that would be greatly appreciated.

[Estoril X5 D Sport]

Are all the hoses heating up as they should and the heat coming through the heater as it should?

If you haven't had the car long then my guess would be that somebody has done the rad weld thing in the past possibly more that once and the water is not getting circulated round the radiator to get cooled properly, check and see if the radiator is even temp all over, also they are bad for heater matrix leaking.

Stephen

[Green-Chameleon]

Thanks for the reply!

The heater blows warm air fine and all the pipes heat up but will check the radiator.