My ignorance... Anti freeze etc...

[Lance Jones]

I'm doing more and more mechanical projects myself as related previously in the fuel filter exchange this summer...
My current project is anti freeze. I know I need to add it. Where do I add it and how much do I add? I checked/searched the posts and gather it is for the muffler and/or heat exchanger...

[Ken Juul]

I generally use 2 gals of the pink antifreeze for the engine.  Probably too much, but better safe than sorry. Fill a bucket with most of the antifreeze, place on the shower pan or inside the head cabinet if small enough. Pull the seawater intake line off the thru hull/strainer.  Use your thumb over the end to keep most of the water in the hose so you don't loose your prime.  Place in the bucket.  Start engine, then stop when the bucket is empty (if using a small bucket, may need to refill as needed).  Drain water out of the strainer, back fill the strainer with some of the leftover antifreeze, when strainer is full, tighten bowl, reattach hose.  Move to seawater pump.  Remove impeller, clean with fresh water, inspect vanes for cracks. If ok, spray with silicone, store in ziplock until recommissioning.  Clean up your mess.

I generally make it the last step in the engine winterization.  First change fuel filters, second warm engine, then change oil and filter.  Last step is the antifreeze, the short ~30 second run distributes fresh oil around engine.

[Lance Jones]

Thanks Ken but,this is not for winterization. This is for constant use.

[Ken Juul]

Then it sounds like you are talking about the other side of the cooling system.  Unless it was previously drained and just filled with water all you need to do is top it up.  If you have an expansion tank, fill it there just like on your car, expansion tank should be 1/3 to 1/2 full.  If no expansion tank, remove the radiator cap on the engine and fill there, tank should be filled to about 1/2" from the top to allow for expansion.  Use a 50% antifreeze solution

If it was previously filled with just water you will need to drain the engine and refill with a 50% antifreeze mix.  Stu made a good post about draining the engine with pictures.  If you do drain the engine, don't forget to burp the water heater and engine when you are finished.

[Ron Hill]

Lance : There have recently been numerous posts on draining and refilling the "INTERNAL" 50% water/Prestone mixture.

If you want to get even more of the "old" coolant you'll also need to suck out that coolant in the water heater and hoses beside just the reservoir and engine block.  Then replace the new 50% mix into one heater hose until it come out the other one.

Also prepare to "re burp" the system if it starts to overheat.  Many posts on this topic.  

If you do not have a coolant recovery system, I'd recommend you install one.  There have many posts/articles on how to build your own like I did back in 1989.  

The information is out there for you in the Mainsheet tech notes on on our web site.  
You might also take some time to read your operators Engine manual - it tells how and has pictures that identify all of the parts on the engine.    A few thoughts