Hi all
Success today in getting one of the heads off. The problem was a couple of the studs being badly corroded to the head and causing the head to only really move at one end. To get round this engine oil was trickled down the studs and this highlighted that the stud nearest to the exhaust of cylinder no 1 was causing us a problem. The solution was to first get the head parallel to the block and by keeping the head under tension by the rope fit a nut to the stud and tap it till I could see it had move down. The next thing to do was slacken off the nuts on the studs at the far end of the head a few turns and give the exhaust manifold a clout, this moved the head up at that end so returning to the no 1 cylinder end some more careful tapping on the stud with the nut on saw that end now go up. This was repeated till the head was off. The stud was very tight and it might be advisable to find a better way of dissolving the corrosion sticking the studs to the head as once revealed it was clear that several of the studs were corroded quite badly.
Clarkey