My, those spark plugs are a bit of a pain to get to aren't they? Several easy, several pretty awkward.
Did the sniff test, definite combustion leak from the colour change, not to mention the amount of frothing.
Started with the easiest to reach pots - front of the right hand bank. Thought my compression tester was duff to start with - turns out instead of a 4 litre V8 we've been enjoying a 3 litre V6. Did double (and triple on the low pots) test for each cylinder.
170 / 170 (1) (2) 0 / 0 / 0
150 / 150 (3) (4) 0 / 0 / 0
170 / 175 (5) (6) 150 / 160
150 / 165 (7) (8) 170 / 170
Variation isn't ideal but I'd live with it for a bit, but 2 cylinders with effectively zero (might have been 10-20 but was off the bottom calibration) is definitely no good. Number 7 plug looks clean / white on the insulator, so suspect that is my coolant pressurization point. Fingers crossed 2 / 4 is a cylinder to cylinder blown gasket and nothing else damaged but I fear the worst. Maybe the camera well tell later. It is too hot and bright out there to be mucking about with that at the moment.