One more stupid newbie question. I'm storing this boat in my yard (as I would have paid 400 to keep it in a fairgrounds barely under a high roof). Anything I need to know beside I have the outdrive up (I scrubbed and waxed it it looks like new, wrapped in plastic with a few holes in the bottom to drain any water. I have taken MOST of the cushions out---I dehumidified the cabin---with our house dehumidifier. I was told by another boater to put a bag of opened charcoal in the hold to absorb odor and moisture? Is that needed? Also this trailer has "surge brakes" is there a way to "lock" my surge brakes just to be sure? Probably not, but like I said I'm new to this.... So much to know....Owned a partikraft 50 hp pontoon boat and bow rider bayliners before SO easy to deal with compared to this big boat.... Do I cover all port holes with duct tape to avoid critters also? how about leaving a fan on all winter inside the cabin? (its gets below zero here in February central pa).... Well thanks again.....
Now that you have the drain plug out, water in the bilge shouldn't be a real problem, and I wouldn't bother with the charcoal thing.
Even if there was a way to lock the master cylinder in the "engaged" position, it's unlikely it would hold brake pressure indefinitely. This is why the parking brakes on cars (which use hydraulic brakes) are cable operated. Go to Harbor Freight and purchase four of those big ol' rubber wheel chocks. Set one on each side in front of the front axle tires, pull the boat forward a bit up on the chocks then set the rear chocks behind the wheels on the rear axle. Let the trailer settle between the two sets of chocks. They'll be nice and tight and that trailer won't go anywhere.
Do not use duct tape anywhere on your boat - that stuff is terrible about leaving sticky residue behind that is real work to remove.
Just keep an eye on your cabin to make sure it stays dry inside. A fan isn't going to do much for you. Did you winterize the boat yourself or pay somebody to do it for you? Are you sure the water supply lines to the sinks and shower are purged? How about the drain lines for the toilet? Water heater? Holding tanks? There is a lot that needs to be winterized beyond just the engine.
Finally, store your outdrive in the down position so water can't collect in the prop, if it freezes it will crack the lower unit.
Please ask any questions you can think of, that's why this forum exists!