I am well aware that boats can be experienced like malevolent beasts. But it sounds like you feel every avenue has PITA qualities and that every proper maintenance and care you attempt will be thwarted at every turn. You have some good suggestions and I will try to address those areas where you express concerns.
I am assuming, in my writing, that the boats we are discussing were left for an over-winter storage and were prepared properly for this and that, with covid, an over-winter storage got extended and the boat became “neglected” because the owner could not get to it. It is quite a different challenge if the boat was just walked away from with no prep and abandoned.
Liferaft maintenance is an expensive endeavor and usually a bother. I personally would not use a weighing method to determine the state of my raft: far too critical a measurement and the down-side of error is too great (contacting the raft manufacturer as to the wisdom of weighing to determine condition might be wise). And, for sure there is lots else that goes into a liferaft inspection/servicing.
And, no: I have no “service agent on tap” nor one that comes at the “ring of a bell”. I am not sure what I said that implied that. Perhaps my saying “get it serviced” made it sound too easy. Quite the contrary: I have been ~~20 years from usual marine support facilities and mostly living aboard and, in that time, I have had a wide variety of raft servicing. My raft’s manufacturer paid for my raft to be couriered from Turkey. Another time I sailed the raft to The Channel Islands from the UK for servicing. Two times I sent it by mail (prohibitively expensive) and one time I was lucky enough to be close to a service facility.
Not sure what point you are trying to make about raft servicing in the telling of boatyard employee(s) appropriating of the heater and cord without permission.
My modern engine is easy to turn over by hand: I am no expert in this area, so talk to your local mechanic or the manufacturer to ensure doing so properly. My take is that there is generally a straightforward way to turn over modern engines by hand. It may be enough to just do the starting technique I suggested and let the batteries and starter do the work, but even there it might be wise to consult a mechanic/engineer you trust.
Oil heating could be effectively accomplished in the way you describe, although getting out cold oil could be a challenge (I am in a cold area). My interest was the oil for sure, but also generally in having the whole engine, block and all, warm before starting. I am unsure how important this is, but not unwilling to extend myself for my engine’s sake, even if of marginal value.
I am not sure bleeding one’s fuel lines is necessary. Why do you suggest this? I would assume that at the end of season Biobar (or the like) and fuel stabilizer would have been added to the full fuel tanks and the engine run enough to distribute the fuel into the engine. In this way, the fuel in the lines should be the same as the fuel in the tank and drawing in fuel from the tank via the lift pump should make no difference. Am I missing something here?
I assume what you mean by “fuel filtering” is what I wrote about fuel polishing. Search the OCC Forum and you will find my fuel polishing method with comments about how it can be generally applied.
You ask about maintenance of seacocks: cone ones like Blakes can be an essay in itself and I suspect googling will get you a youtube demonstration that will transcend any written description. In short: I have had ball valves for decades now and would not go back to cone style. Maintenance includes: 1. Working all seacocks once per month during the season and more often if they prove to be stiff or barnacles etc. are fast growing: 2. At spring commissioning spraying lubricant grease into and around the seacock from outside the boat while someone inside is opening and closing and working the seacock: 3. Do the same at lay-up (if on the hard) and leave the seacocks open to ensure no water accumulates later to freeze and damage the seacock. 4. Some seacocks have the capacity to use a zerk fitting for a grease gun making lubing much easier. And the above efforts, for sure, will ensure the seacocks are tried out on land before launching as you correctly suggest.
With the above, I have never had a seized seacock, stiff at times, but never seized: I am sorry you find yours “usually seized”.
I did not neglect a warning about heating near penetrating oil in my previous writing that you are responding to and wrote: “watch for igniting the penetrating liquid”. But warnings like that bear repeating. If worried about heat sources, wrap the seacock with a towel and pour on boiling water: repeat and the seacock will be warm with no danger of igniting the volitiles.
It has been my experience that a properly maintained and prepared toilet, holding tank and hoses done at lay-up is not smelly at the end of the lay-up period.
And multiple impellors should be part of any wide-ranging vessels stores. I replace my impellor every year even if it looks “like new”.
Thanks for your thoughts, My best, Dick Stevenson, s/v Alchemy