Originally Posted by Gdavid
You need to consider additional factors other than flow rate for your circulation pump. The flow rate and head pressure requirements for the circulation pump are really quite low but the pump needs to be continuous duty as it may run for days on end without break. You will also want a quiet pump. You want to have a AC voltage powered pump because that is what you need to power the air conditioner anyway and running a DC voltage pump continuously will require constant charging of the batteries. When you consider these factors it helps justify the ~$230 cost for a March pump. The magnetic drive these pumps have allow for a long service life because they don't have a shaft to seal and they protect the pump from burning up the motor if (when) you get a blockage. The guy on thehullforum used a fish tank pump which would have most of the features you need but keep in mind that these pumps are not self priming (neither are the March) and therefore need to be located below the waterline. Any plumbing below the waterline connected to the sea presents a flooding opportunity if the case breaks and a fish tank pump is not engineered with this in mind. A fish tank pump's motor isn't ignition protected either but less of an issue for a diesel boat but something to keep in mind and could pop up on a survey.
It is smart to keep an open mind for alternative ways to accomplish things but remember to carefully consider why the conventional products are used. Before you buy a used unit, try calling around a bit and see if a scratch & dent or open box kind of unit is available. An installer may have a decent used unit that most boaters would not pay to have installed but would have value to a diy boater like yourself.
Thanks so much for the info on the pumps. That's why i'm here.. To learn.
After talking to some guys at the marina it seems like a trade off. A couple guys worry about the boat sinking due to thru hulls for their AC and say the grass isn't always greener.
The rooftop AC is going to stay either way so i'm just using it for now. The portable unit in the Berth has to go. I'm considering simple window unit with an adapter in the front bow hatch "for now". It would clear up some space.
Originally Posted by Alaskasbear
Are you sure its 200hp? Mine is 165hp. Same year as yours. I didnt think the 200 hp came out until 81-82. Top speed is 12 knots WOT. Cruises at 7-8 burning about 1.5 gph . WOT is about 4+. My flying bridge has some rot as well. Project for the fall as well as re coring the cockpit with new hatches.
You know what i'm not sure. I checked out the engine but didn't write down the serial/model number. I'll check it out this weekend. I honestly would prefer the 165 because finding info on the 200 is much more difficult(i'm in no hurry).
Definitely doesn't seem to use much if any gas. I have been on 4 outings, running the genset alot and the fuel gauge has barely moved. Seems like 220 gallons would last me the year.
I have rot on the flybridge and on the back decking. The back decking will be a much easier job so I plan to tackle that "soon".
The flybridge needs support from the bottom to be sorted out correctly and I will probably wait until winter for that.
In my area a fully kitted out restored boat goes for around 45k.
Found some boats with solid decks but needed some engine service(and little to no electronics).
I'm not afraid of fiberglass work and @ 25k felt like I did good for a boat with radar, autopilot, new plotter,etc. The electronics are expensive but fiberglass is cheap(fiberglass work done by a pro/another story).
I got a quote for $3,000-6,000 to fix the flybridge/rear deck and i'd seriously consider paying 3-4 grand but 6.. I dunno.