Hey guys, im a new rotary engine guy. Just bought my 1984 Rx7 and was cleaning the engine. Afterwards i opened the oil cap and saw a white grease (water build up) i looked at where the water could have got in and there was a crack on the oil cap and a missing tube on the shaft.

So my question is how to i get the water out and is it safe to start?

 

That 'white grease" is actually condensation from the detergents,etc in the oil.
Oil heats up and cools down..town driving/stop and go,..short jaunts to the store etc..SPLUCK!
This is kind of normal in a rotary engine.(they call it "lung mustard"!)
The fact that your oil filler tube is not running to the charcoal cannister would have something to do with the Excess you see.
You could use proper venting of the oil system or a catch can to minimize this.

 

Oh ok! Thank you @Misterstyx69. That makes me feel a lot better. Ill see what i can do about that oil filler tube!