the outdrive it self in the down position is self draining as long as the drain holes are clear. I spalsh some af in the prop hub to take care of any residual and if you leave it outside you should cover the prop ub so no snow/ice or leaves get in.
If you are worried about a new to you boat...
as bondo mentioned it come up through the manifold bottoms and out the risers.
The separate hoses feeding the elbows supply cooling water to the exhaust when the thermostat is not open. This is a warm manifold system vs the cold manifolds with only the supply to the manifolds that is supplied...
you can always pour some AF in the thermo and it will come out the block drains eventually. After I drain mine then put the plugs back in, take off the hose coming up from the outdrive (at therm hsg), I have a short piece of old cut off radiator hose that has a 90 in it so it points up easy to...
When I bought my new GM long block from Michigan motorz a few years back they insisted on rotella T4 conventional 15W40 for break in. Also wanted conventional oil for first 100 hrs before switching to synthetic
Your lower temps may play into it but I’d think you’d be fine using it. Long block...
Parts breakdown for your upper 3&4 are plugs for that, one is threaded and one Welch plug
https://www.marineengine.com/parts/mercruiser-sterndrive-parts/rmralpha-one-transom-assembly-19831990/6216687-thru-0d469858/driveshaft-housing-and-drive-gears
normal this time of year, goes dormant unless someone has a project going.
If you dont have it get manual 14 for the gen 2 drive very helpful/good info
do you mean you have lube leaking down the shift shaft in the bellhousing onto the lower ? This may be from the poppet valve in the gear lube line. If you dont pop the drive on quickly any residual lube in the line will leak out when the drive is an inch or so off the bellhousing.
no good deed goes unpunished... On my entire drive the only seal that was somewhat compromised by wear/age was the shift shaft seal. All other seals were in nice shape, except for the prop shaft seal with fishing line...
So you had no leaks - just replaced the seals while you were in there?
I tried just replacing the seal on the shift shaft not the whole plastic housing it is in, could never get the seal to to stop leaking , ended up buying the bushing with the seal in it.
Sierra is better than most aftermarket parts, but the OEM is best in my experience. My boat is a 2004. two...
verify the thermostat is opening, would not be the first time a new one didn't work. Put it in a pot of water see what temp it opens at and if it opens fully.
most likely the carrier seal below the water pump. relatively easy to split the drive remove the water pump and pressure test the lower by plugging the hole where the quad ring goes. Usually can clamp a flat piece of metal on it.
Get 12-15 psi of air pressure in there and put soapy water on...
where it connects to the lower is not what I was talking about.
There is a clip farther up the tube that holds it to the bellhousing casting. The clip goes into a 1/4“ hole in the bellhousing , i suspect this where the water is coming out.
you will have to look farther up in there than where...