R-21 full-time Bilge pump

[SlackwaterJack]

Has the Factory looked into full-time bilge pumps that install on the propshaft and run whenever the boat is in gear? (you don't need to remove the shaft to install. (www.fastflowpump.com) The manufacturer says that their smallest size can move 24,500 gph at 2000 rpm. This type of pump operates fulltime, whenever the engine is in gear plus it ventilates below deck when it isn't pumping water (hopefully never). Given that a failed packing gland or a sizable hole below the waterline can overcome most 12v bilge pumps in minutes this seems like an item that could equate with airbags on cars.

Given that the R-21 doesn't have passive cockpit drains this could be a good idea to include either as an option or standard with new boats (even the 25's and 29's). I'm sure a kit made available to existing boatowners would also be well received.

**I previously owned a 1968 Albin25 powered by the AD21 diesel. She had a full-time bilgepump ( approx 500gph) that was run from a belt on the engine and therefore didn't even need to be in gear. I don't know if Yanmar makes a double PTO pulley for the engine you use on the 21 or if there would be clearance for a "fist" sized pump.


Alex G.
( a soon-to-be R-21 owner)

 

[Tom Ray]

Sounds like a good idea to me. We had a severe thunderstorm here yesterday, showing 4 inches of rain falling per hour. In a collector basin the size of the 21, that's a LOT of water in a short period of time, if you happen to get caught out in one of those.

 

[Andrew Custis]

I looked into these over the weekend. They tie into the prop shaft so what do you do when the boat isn't running?

The other problem I saw was the size. Seemed way to big to put in the R21.

 

[SlackwaterJack]

hopefully the boat is moving when you take a big wave over the stern, hit a submerged log or get caught in a torrential rain. You can still make it to safety or ground the boat before it sinks. I realise that most boats sink at their slip or moorings so it wouldn't be of much use in those situations, but the loss of life situations generally involve boats in motion. Didn't htink it would fit an R-21 but an R29...maybe

 

[rt11002003]

Have we talked about having the raw water pump help if taking on more water than the bilge pump can handle? Not that I believe a R-21 would take on solid water. 😉

I believe one can attach a piece of hose to the fitting between the sea water screen and the raw water pump and put the other end into the bilge. That little pump moves a fair amount of water.

I've noticed a couple of times recently that my bilge pump seems to catch small amounts of trash causing it to try to run, but can't, because there isn't enough water. It moves a little bit of water up the discharge hose, then it stops running; the water flows back and the cycle starts over. I stop the cycle by dumping about two gallons of water thru the small hatch behind the engine box. Seems to flush it out, at least for awhile.

I pulled the tug this morning to put bottom paint on it. While it's out I'm going to flush the bilge. Ranger did a pretty good job removing the construction debris, but there's some around as I'm finding out.

Gene

 

[rustednail]

Gene,

The bilge pump should had a check valve installed in the outlet. It looks like a rubber nozzle, similar to the one in the engine flush adapter. That should stop the water from running back into the bilge after the pump shuts down.

When you get your boat back in the water, I would love to hear some feedback about any degrade in performance. Will the bottom paint affect the speed? I'm guessing (and hoping) any performance decreases would be so small that it wont be noticed. Ya know, parasite drag increases with speed and we do not go that fast.

Bri

 

[rt11002003]

Bri,

I think the check valve is where the debris is catching. It works ok, after I throw all that water below, probably flushes the debris on thru.

I'll check top speed as I take the tug back to the marina and let you know if the bottom paint makes much difference.. When I first checked top speed I was in the 9 to 9.5 knot range in flat water, light to no wind and my usual min payload at 3350 or 3375 rpm (my max attainable at that time). After my little fuel contamination problem, I can't get much over 3300 rpm. But, that may be due to slime on the bottom. Also, on Monday my doctor told me the pain medicine I'm taking may be the reason for my three pound gain 😉 and it may also cause my feet and ankles to swell. 🙁 Almost anything will cause one to lose max rpm. 😀

Gene