Head and Shoulders

The hardest part of the engine build is behind me with the crank and crankcase assembly complete. I put in about 4 house in the garage today to get as much done on the engine as possible before it goes back into the frame. The exhaust manifold is soaking in a diesel bath to aid the de-coking, I want to put on the engine before it goes into the frame. I'm going to have to spend a few hours organising the space to make the bike rebuild easier.

Top End Refurbish

I attacked the top end of the engine with the dremil and stainless steel wire brush to remove the corrosion. I started with masking off and sealing the barrel and protecting the gasket surfaces from scratching etc.
Here is the before and after >

Engine Breaking

This weekend I attacked the engine. It is getting a total stripdown, I need to clean all the casings to remove oil and corrosion. It seems the head gasket/seal was shot so there was oil and coolant mixing away.

Engine out

Finally got the engine out and this obviously made it easier to inspect the damage and general state of things.
Again as mentioned there is heavy corrosion on the alloy and 1 problem which is a bit serious looking, there seems to have been oil/water leakage somewhere in the engine. What looks like emulsification can be seen at the cylinder head on the pic below.

The engine type is the Rotax 122 model.

There also seems to have been a leak at the powervalve area highlighted in red. I'm wondering is this the source of all the goo ?