I did not explain my problem very well. The leak is in the combustion chamber. The alloy is very pitted and a hole has developed in one of the pits. I was looking at a product called JB Weld that claims to withstand temperatures of 300C..thus my enquiry re temperatures. I have also been looking at web sites on electroless metal coatings etc as it would appear that it will be very difficult to get it welded.Are there perhaps alternatives that I haven’t explored ? Buy a new head !!!!!!
