[mike1967]

Ok so I replaced the reservoir tank and cap with a new OEM one last night. Was bleeding the system and as i was doing that same thing happened. The coolant started going up and out of the cap.

when bleeding them only put just enough water each time that can see it in bottom of the filler neck this will allow air out without throwing the water as well its painful slow have heater on full hot, even worth jack car up at rear can help clear air from rad same as jacking up at front can help air out of heater pipe work, i would do a sniff test on it for piece of mind link below will tell you if carbons in water jacket from cylinders it turns yellow if there is, save any guess work

https://www.ebay.co.uk/itm/BT-3-BLO...959824&hash=item4200fe5f0a:g:MuUAAOSwLEtYi8Gi
they are prone to gasket failures with age and mileages

 

[mike1967]

Ok so here I go again. I rebled the system and still same issue. I check the fans with direct 12v and the low fan doesnt turn on while the high does with direct 12v. If thats the issue what can be causing the low fan not to work? Do i need to replace the fan assembly?

fan resistor
https://www.ebay.co.uk/itm/Heater-B...e:Mini&hash=item4d89fb9538:g:NsEAAOSwfgRcART8
or one of the fan relays link below

https://www.ebay.co.uk/itm/BMW-MINI...984893?hash=item2ceaced67d:g:QW8AAOSw7XFc3F7N

first would check voltage at fuse box and pull tops off relays and check them, ie they have a big amps live in that is switched by a smaller 12v feed from ecu controlled by the coolant sensor and if have aircon

 

[mike1967]

i always wondered if a simple mod could be done with gen 1 mini's ie put a t-piece in to the heater feed pipe and put a pipe from it to a gen 2 header tank like just about every car on road has, if can have 2 inches of air to expand in to might need to run a small pipe to top radiator hose some how, that would self bleed out better, one day a gen 1 will turn up and i will have a go at it see if its possible to improve it,, really do think it would so do away with filling it at cylinder head

 

[mike1967]

below link 16mm t piece
https://www.ebay.co.uk/itm/16-mm-OD...062185?hash=item23a11fa9a9:g:8joAAOSwdzhb8x9U

16mm pipe and clips
https://www.ebay.co.uk/itm/16mm-FUE...=20228599259696626e216b64454784ef50e8f968e7a9
mini r56 header tank
https://www.ebay.co.uk/itm/MINI-COO...146156?hash=item59207ce82c:g:M-gAAOSwcntcbG4f
just in case someone wants to try it