seem to have gone. basic conclusion - if you dont tighten your head nuts as per the specified maintenance
schedule (in my case every 250 hours) the head will get a bit loose and start leaking. There were signs of leakage from no 2 cyl into the water
galleys on the air intake side. I backed the tappets off 1 turn when removing the head.When the new gasket
was fitted and torqued down, it was about 2 turns to get them back to the proper gap - more evidence that the head nuts had loosened. Back together and running sweet, needs a good warmup run and another torque, then pretty much back to normal. Also found a few little things that were about to let go in the process, nice to get them before they caused problems. A couple of beautiful sunny winters days wrenching on the water
, what could be better...