There’s a square edge on the radiator support that can rub the heater hose. Take a look directly below the TMAP sensor on the front of the intake manifold. The hose picture is taken from below; those two wear spots are very thin. The fix is to slice the offending corner off and file it smooth.

 

A new rub meant more material removal. When the coolant gets hot the hose expands and moves forward; without the corner in the way it kept on going to the next edge. There is an extra spacer on the modular front end now and it still wasn’t enough room.

 

Do you think its possible to slip a tool in there to shave off some of the plastic?

 

Yes it's possible with lots of caution. I recommend "service mode" to keep the hose out of harms way and provide room for sanding the plastic smooth.

 

K-huevo, Thanks for the tip, checking mine soon.
I had this happen to me in my last car. Rubbed a hole on a HOT summer day in Washington DC traffic. It wasn't a MINI, man I was really freaked out about that all aluminum engine getting wasted. mdsbrain, I see your concerned about over heated engines too.

 

The subframe was lowered to do some suspension modification and I discovered a major abrasion between a power steering hose and a heater hose. The heater hose was almost worn through. The stock replacement heater hose was on backorder and eventually was released from Germany but stayed in customs longer than I could tolerate. I found a hose with one similar bend which I cut down to become the alternative.

To check if your power steering hose is in harms way, follow the forward hose from the steering fluid reservoir down toward the heat shield. Directly to the right (driver) side is the heater hose, if they touch loosen the nut on the reservoir clamp and twist the reservoir to move the hose. The heat shield edge may have to be bent to accommodate the new hose position.

 

My mechanic informed me last week that one of the A/C lines on my 2004 Cooper has been rubbing against the CVT case. He bent a mounting bracket to get the line away from the transmission, but the damage has been done. The outer rubber sleeve has been worn away, exposing the steel braid underneath. The hose will likely have to be replaced.

The next time I'm under the car, I'll snap some pictures.

 

Thanks Keith, important and interesting. Will have to take a look.
JS