40.5 Macerator Pump Won't - Where is it?

[Rich Stidger]

Sadly, my worse fears were confirmed. My macerator pump runs but doesn't pump anything. I thought that the WEMA sensor might just be stuck, but after cleaning it (it was a bit gummy) the level doesn't go down. The sound of the pump doesn't change and I am certain that it is not pumping.Now the question is: On a 40.5, where is the pump located and what do you have to do to get to it? I know the tank is under the cabin sole next to the NAV station and I think that the pump is under the foot platform of the NAV station, but I'm not sure.Is there anyone with a 40.5 that has serviced the macerator and can tell me what I have to do to get to it?How susceptible are the hoses to plugging? What steps do I need to perform to service this pump? I presume that I need to get a pumpout before starting the work.Rich

 

[bob]

40.5 macerator

hi...i've just replaced the macerator in my 1995 40.5....it's underneath the chart table seat, and is not dificult to reach bob s/v reliance

 

[Peggie Hall/HeadMistress]

Replace the impeller in the macerator

When the motor sounds fine, but the pump doesn't pump, it's a 100-1 bet that the impeller is shot. Impellers are neoprene...friction heat from running dry till they prime, freezing during winter layup, lack of use...all take their toll on impellers...till they no longer impel anything. If you want to avoid having to replace it when the tank is full and "Stuff" is in the hose between the y-valve and the pump, change it every spring as a part of recommissioning the boat.

 

[Patrick Ewing]

First check the deck pumpout cover to see that

it is properly seated and tightly sealed. I replaced my pump twice and rebuilt it once because I didn't realize that the pump pulls the stuff out of the top of the tank and that my cap was leaking air into the pump. You may not need to pump out the tank to fix the pump. I would suggest that you check that very carefully though. My boat may be different than yours.

 

[Peggie Hall/HeadMistress]

Pat, if the y-valve closes properly...

...it'shouldn't matter whether the deck fitting is open or not. OTOH, if you don't have a y-valve--just a wye or tee in the pumpout line--it would make a difference.

 

[Patrick Ewing]

No y-valve here just a t fitting

There is no y-valve on my system just a t-fitting that goes one side to the pumpout deck fitting and the other to the macerator pump. There is a thru hull after the macerator. Is that common or should I add a valve?

 

[Peggie Hall/HeadMistress]

I prefer y-valves...

...close to the macerator. 'cuz if the macerator fails when you have a full tank, a tee fitting doesn't do much to "stem the tide" when you take the hose off the macerator. It's good to be able to close the line.Btw...you should also have a vented loop in the line between the pump and thru-hull...and it should be at least a foot above the waterline at any angle of heel.