I am attempting to drain my 6L for the first time, and encountering surprises or possible issues, or I don't know this motor like I thought. I am following this diagram;

I disconnected the inlet hose to the transmission cooler (1 in diagram) and the raw water pump outbound hose (#2 in diagram), water comes out fine.
For #3, Fresh Water Drain, is located in the middle of the heat exchanger, and will drain coolant. The Raw Water Drain is located on the passenger side, more towards the top at like 2 o'clock. Here is an image;


When removing the Raw Water Drain, nothing comes out as it is facing upward, should I remove the hose coming from below?
When removing the the Exhaust manifold hose (#4) and the Exhaust corner drain plugs (#5), radiator fluid, or at least a mixture of predominantly coolant comes out.
Therefore, in following the instruction manual, as well as guidance from others, there seems to be something going on for coolant to be coming out.
Here is a link to the manual I am using;
https://pcmengines.com/wp-content/uploads/2017/09/imagesOwners-Operations-Manual-2011.pdf@Jody_Seal hopefully you may have some insights.
Thank you for any help and recommendations.
Comments
You can trace the fresh water intake hose to where it enters the heat exchanger, disconnect and let water drain. Also pull plugs 4 and 5 on both sides. Something is really odd if you are getting coolant out of these. By using the RV antifreeze, its not absolutely necessary to drain first, but a little overkill won't hurt.
Anyway I agree 100% with Bruce. Although I don't run antifreeze through the system like he recommends I do think that's a very good idea. Basically just trace the hose from intake through the system, disconnecting as you go with focus on the lowest points. At the exchanger you may accidentally disconnect the wrong hose (done it more than once) and coolant will come out instead of water...good times but an easy fix to just add a bit more in the reservoir.
Good to know a couple others with this engine type on here...
@Bruce_Butterfield are you running it when or after you put the antifreeze in the intake hose?
To run the RV antifreeze through, disconnect the strainer hose, start the engine and slowley pour the antifreeze in the hose. A break of a handful of seconds without pouring anything in won't hurt anything as the impeller will still be lubricated and it will be turning slowly. Keep the engine going until you see pink stuff coming out the exhaust.
I change out the impeller and fuel filters in the spring before putting it back in the water.
The only thing I can think of as a difference in the sytems is the half system had a smaller black heat exchanger and the full system had a larger grey heat exchanger. That is compared to my other 6L engines.
I don't have the 2011 anymore so I can't take photos to share with you.