the torque generated by the compressed air starting means we only have to lgo about 1 turn before we are going fast enough to put fuel into the engine and start it. This is important as when the ship is manouvering we can't just drop the clutch to go into neutral as we don't have one the propellor is bolted stright onto the end of the engine. This does raise the intresting question of how do we go backwards?

The answer is to most people kind of silly. We stop the engine change the camshaft and then start it backwards and then we have reverse. The process takes about 30 seconds from running ahead to running astern.
instead of changing the whole cam what we do i to retme the cam shaft in the engine. On each section of the cam there is two fuel cams and two exhaust cams mounted ontop of a servo motor which is hydrauically actuated so to go backwards the engine is stopped and then we pump oil into these motors to swing the cams on the cam shaft which turn them and then we have the engine retimed and then we start it again but in the other direction

As to normal working temperature what is done is when we are stopped there is two steam heaters one for the fuel which keeps this hot and we circulate it around the injectors through some clever valves that close when the pressure in the fuel line climbs above 80 bar to allow injection to take place. This heater also runs when we are at sea to heat the fuel but then the circulation is still going but now it is there to cool the injector so the fuel doesn't get to hot leading to poor injection.
The other steam heater is in the cooling water jacket line which heats up the water so that the engine is kept about 70 centigrade when topped climbing to 88 centigrade when running.
Once we are running this heater is switched off and we then pass the jackets through a thing called an evaporator where we get a container and run two sets of tubes through it. one set at the top and one set at the bottom. We then get a sea water pump and pump sea water through a device called an eductor (venturi effect) which produces a suck then using this suck we create a partial vacum in the container. tehn we take the sea water from the eductor and pipe it through the top set of tubes called a condensor. Then the seawater from here is taken and most of it goes over the side back to the sea but some of it is piped into the bottom of the contianer under the lower coils. through these coils we put the cooling water from the engine which heats the seawater to about 70C and it then boils due to being in a vacum and the steam goes up the way and is condensed on the condensor and it then falls onto a tray and we pump out the condensate and we have fresh water and the remaining brine in the container is pulled out by the eductor to ceate the vacum.
This helps to increase plant effiecency as you get fresh water for almost nothing.

Another way to increase effiecency is the hot exhaust gas is used to make the steam needed to heat the fuel.

As to time to get from stopped to full speed it is about 2 hours as we don't want to over stress anything with too rapid an increase in temperature.