Re: Overheating/coolant issue
It sounds very much like your heat exchanger has breached and you have overheated. I liked the idea of the washing-up liquid and check for bubbles trick. Take off your heat exchanger and have a wee look. It should be apparent where the breach is.
When your motor stopped from overheating, you will almost certainly have picked the pistons up and scored the bores a bit. The bottom end of the motor should be OK though as it was not an out-and-out lubrication failure.... that is much more damaging scenario. I have been there with that one... twice.... and survived it without too much damage.
Keep an eye on your oil consumption for a while.
If you are starting OK, and the revs are stable, then I would just live with it. Just keep topping it up and carry plenty of spare oil.
An oil and filter change after you have fixed it all would be an idea, too.
The BMC 1.5 is a sound and orthodox motor.
It has been running in London taxis for decades.
Last edited by Rockter; 12-07-2012 at 11:36 AM.