X15 Engine

[Rawze]

The only times that I have seen signs of green moisture buildup, green sludge at oil cap, crank case filter, inside engine cover + a bit of coolant loss ... it was always a sign of a head gasket seeping/starting to fail.

The proper way to find/test head/gasket is to drop the oil pan (and stiffening plate) off of engine and pressurize the coolant system to 20-psi over night using a coolant pressure test kit.

- Then the next day, look for any drops of coolant on the bottom of the engine mixed in with oil near the bottom of the pistons, bottom and inside walls of the liners, etc. with a nice bright flashlight.

- If it is only seeping a bit then it can be hard to spot ... However, after it has sat over night with pressure on the coolant system, oil pan off of it, if you have someone turn the engine by hand with a large wrench, and listen to each cylinder as it starts to hiss on a compression stroke while your laying up under the engine .. if there is a head gasket issue then that cylinder will "gurgle" a bit as it comes up and you can see a few drops of coolant sneaking out around the rings as it does this.