My 92 130 Yamaha ran great today until heading back to the boat ramp it did not sound right . I did not have full power to load the boat on the trailer. I checked spark, compression 130 on all 4 cyl. When I looked at the #2 plug then I had seen that it was milky. I went home and had extra head gaskets and cyl jacket gaskets. I changed them and torqed. I took the boat out again and still water on number 2. The first gaskets looked good but I asumed after seeing a milky plug it was one of those. What else could it be.