Failed S1 Heater Matrix/Radiator

[LCR1967]

What are my sourcing options for a replacement heater matrix? The original is badly corroded and is springing leaks in so many places. As soon as one hole is brazed and the unit retested another leak, or two, or literally three crop up elsewhere.

[nistri]

Any good radiator workshop should be able to replace the matrix.

[Spider2]

I need to remove the matrix from my Series 1 sport and cannot quite work out how to do it. Was your a coupe or sport? The posts I have read mention 4 long bolts that protrude into the engine bay and have to be carefully undone from underneath but I cannot locate these bolts.

[nistri]

Indeed, there are 4 setscrews (or bolts) at the lower part of the unit containing the matrix. Two at the front and two at the back of the unit. Not easy to locate them and being a contortionist is of great help. Of course, hoses and cables have to be disconnected as well.

[LCR1967]

I also removed the lower dashboard, and the lower front console where the speaker and cigarette lighter are located. As nistri stated all mechanical connectors and hoses, inside and out need to be removed.

[Spider2]

Mine is a series 1 Sport with the heater cock in the engine bay. The bottom (top) of the set screws are supposd to be sprayed with penetraing fluid before attempting to undo them but I cannot locate them. Are they under the air scoop which obviously has to be removed to get to the rubber pipe atachments to the metal matrix pipes.
Another strange thing is that when I remove the pipe from the heater side of the stop cock and run the engine no water comes out of the stop cock (so membrane is OK) but water comes out of the pipe from the matrix (the inlet pipe). When I turn engine off the water stops. It is almost as if the water in the heater has reverse flow!