Reply To: Ethanol in Petrol, engine coolant and tyre pressures

…. and if all that fails, ther is every possibility that the water jacket in the block is silted up, specially if it is a long time since anything was done to it.

Try removing the engine drain plug – on the left close to the distributor.  If  the coolant does not flow very freely wth the plug out then the block is almost certainly clogged up.  (Don’t forget to place a contaimer underneath to catch the liquid so you do not loose your ant-freeze).

I had a Light 15 that was overheating even in winter.  When we removed the drain plug the coolant did not flow at all and we finally put a 6mm drill bit in to clear a passage.  There is little room on a Light 15 so that was not easy and the bit had to be “twiddled” by hand.  I reckon we drilled over 30mm through solid compacted silt before breaking through to the coolant.  The only way to cure that was to open the engine and literally chisel the crud out of the block.

B……………….