I thought for sure I had posted this in this forum last season(?) I can't find it
sucking antifreeze out of a bucket is almost right- I use Propylene glycol AUTOMOTIVE Antifreeze , NOT the pink RV stuff , Sierra / Low Tox
find it @ Tractor Supply , Ace can order it
hopefully you added fuel stabilizer to your fuel on your last outing, if not do it now
I prefer stabilized fuel and as little of it as possible left in the tank, 1/2 tank is least desirable, Full tank is ok , but you end up with a full tank of stale gas
in the spring, so burn it off wakeboarding, not barefooting. Stabil is the crowd favorite, but lately I've really come to like "Sea Foam" it's in a metal 1 pint can
(good stuff)
I like to pull the intake hose off @ the trans oil cooler input side then I can clean the debris out of it (mostly for those without sea water strainers)
(I have a 3-4' length of hose and attach it to the cooler and place the other end in my bucket)
before you run it on your bucket of antifreeze run it on fresh water to get it to temp, position the trailer so the water goes away from the boat
not under the boat.
get it up to operating temperature so she starts back up right away and idles smoothly
have all your other supplies ready too, spray fogging oil for carbed engines and TBI , multi port port motors are DRY intake and need to stay DRY
so do not fog your MPI
Drain the water from the block and exhaust manifolds, manifold cooling hoses, water pump hoses etc
the less water in the engine and surrounding hoses the less your solution will be diluted
re secure the drain plugs / hoses etc (EFI carefully remove knock sensor, drain , re-install)
some of us like to remove the t-stat - when removed it allows a more direct path to the engine for the antifreeze,
(the housing does have a small bypass hole, so this is not manditory)
without the t-stat installed there's a much bigger path. otherwise most of the solution will go right to the exhaust manifolds.
remove the spark arrestor
fill your bucket with antifreeze solution good for your area ( mine will be good for @ least -20), usually 4-5 gallons
fire it up and let her suck it down (another reason Fake a lakes suck)
with about a gallon left start spraying your fogging oil down her throat choke it out just as the last of the antifreeze gets sucked down
what's left? put it all back together , did you change your oil yet? I might have done that while the water was draining from the block
but be careful you want water out the transom drain , oil drain hose out the center drain (garbard drain if Ron is reading)
if your engine is @ temp your oil will flow freely, if not it takes FOREVER. (and now you know why you want it dry under the boat

fresh oil and filter in the fall not the spring, double check the level before you clean up
fix anything else that may be broken or worn out do it now b4 you put it away for the winter.
cap, rotor , wires, & plugs (?)
grease rudder shaft
remove the battery from the boat, put it somewhere that will be above freezing and NOT directly on Concrete
trailer maintenance
CLEAN THE BOAT wax it, get the carpet dry, ETC ETC ETC
Did you reinstall your T-Stat? (I use a perma-seal gasket RTV instead of a new gasket)
Electronic gauge owners carefully take the little hoses off @ the MDC to drain any water that may be there, if not you'll be calling me in June
about the only thing required to do in the spring is reinstall your freshly charged battery
insert transom and center / garbard drain plugs
and top off the tank with fresh fuel, everything else should have been put back together b4 winter..........
that about covers most of it
good luck or bring it over
Dan T