Macerator pump-- really that bad?

[ernst]

Originally Posted by Cadence

If you hadn't eaten it first or wiped your butt with it don't flush it. A macerator should give you good service.

BUT if someone on board is a Cherry seed swallower you will be pulling the pump apart and probably xmas day!!.

[Cadence]

Originally Posted by ernst

BUT if someone on board is a Cherry seed swallower you will be pulling the pump apart and probably xmas day!!.

I may have posted it the other day. A sink garbage disposal might work well. It seems they will grind most anything and it they jam a hex key will free them up. Maybe they require to much power. Oh, just drag a three mile extension cord. Or a gen. set aboard.

[Connemara]

Why not go with a Lectrasan?

Connemara

[marlin driver]

Jabsco macerators work well and should last for several years. I'm a powerboat guy but I have 3 on my boat, one for the holding tank and 2 for fish boxes. They are all at least 5 years old and still going strong. That being said, I keep a spare macerator and a spare freshwater pump on my boat and can swap out if needed. They do eventually fail and its not a tough swap.

[Cadence]

Originally Posted by Connemara

Why not go with a Lectrasan?

Connemara

Are they legal? I think I have two, or my son might. Is direct discharge legal?

[MC2019]

If you are redoing it stay away from macerator pumps. They require power and when they full what do you do then ......

The valiant 50 I delivered up the coast is a perfect case. 2 am and we are heading out of dana point, owner decides to run the macerator pump to empty the holding tank. Suddenly there is a smell, he checks under the v birth and poo is flying everywhere. Instance sea sickness across the whole boat. He asks me what to do and I told him put the bucket over the pump and run it to empty the tank. Then use bucket to rinse down everything including the bilge and pump over board.

First project I did on the boat once it got to Portland was to replace the macerator. I sold the owner on the idea of using a nice hand diaphragm bilge pump. The can be found any were, easy to replace, very robust, and very quick to empty a tank.

It's the only way I will go on every boat I have.

Originally Posted by Folie

Hello all-
I am considering re-doing my sewer system to include a macerator pump. I would replace the old (BIG) fiberglass tank with a new smaller one. I would hand pump into it and then , when offshore, eject it with the macerator pump thru a new thruhull.

Then I logged into Amazon to check out the pumps-- and the Reviewers told me to STAY AWAY from J-b-c-. They said the pumps are held together with brass connectors and they corrode, fall apart , and then ----- uuuccckkkk-- in the bilge!

Do you all concur—am I asking for trouble?? OR-- is there a brand out there that is built better than Ja-s-o?

Thanks a lot--

Rick--

[Dockhead]

Originally Posted by K_V_B

Why not just mount the small holding tank high enough, en just use gravity to empty it. That is how it's done on many boats. Any (macerating or not) pumps go between the head and the tank, not the tank and the outflow...

Actually, macerator pumps, not integral with the toilet, go between the tank and the outflow.

When used with non-macerating toilets, they ensure that the waste is chopped up before it goes overboard, which reduces the risk of clogging and makes it break down much more easily in the sea, so definitely a good thing.

When used with macerating toilets they are somewhat superfluous, but if you need a pump anyway then why not use a macerating one to be sure everything is properly chopped up.



Gravity tanks are KISS, but relocating holding tanks to get them above the waterline may be more trouble than it's worth. Plus, they are more likely to clog, and not as environmentally friendly. I'll take the macerator, over a gravity tank, personally.




To the OP's original question -- I can't say whether Jabsco macerator pumps are good or bad, but I have one in my boat which is 15 years old, and it works fine. They look robust to me. Parts are easily replaceable and readily available -- I keep everything except the pump itself in spares. I have burned up impellers when someone switched on the pump with the sea cock closed, but I guess that would happen to any of them. YMMV.

[Ironman162]

My boat has TMC electric marine toilet that macerates it all before going to the holding tank. It has never given any trouble at all but does draw a lot of current.

The stalling current is 80A at 13.8vdc and ut needs to run a minimum of 10 seconds.

When the batteries are a bit low you can hear how the motor struggles at a lower tone. Its amazing how a small drop in voltage creates a big difference in the speed of the macerator motor.

The way this is set up means you use the macerator often. I have found that if a macerator pump is not used for long periods it tends to freeze up.

Hope this helps and I don't think you will regret installing it. It is a good addition to a boat.

[Funyacht]

I set up an overboard discharge plumbed to both my MSD tanks. I am on my third Jabsco pump (the last two were obtained at no cost). The first two failed quickly. I would recommend a Jabsco pump to someone you absolutely despise and leave town before they install the pump.

[Mojadito]

Forget the Jabsco Macerator, the design (1-1/2" In, 1" Out) is a recipe for trouble. All waste plumbing systems should get larger, the further they travel. The Sealand T12 (1-1/2" In, 1-1/2" Out) is the only motorized solution. I have had one installed for 8 years (liveaboard) and have never had a minutes trouble.

[marlin driver]

Originally Posted by Mojadito

Forget the Jabsco Macerator, the design (1-1/2" In, 1" Out) is a recipe for trouble. All waste plumbing systems should get larger, the further they travel. The Sealand T12 (1-1/2" In, 1-1/2" Out) is the only motorized solution. I have had one installed for 8 years (liveaboard) and have never had a minutes trouble.

It's a macerator, meaning whatever goes in gets smaller before it goes out. It's also gravity flow in and under pressure on the exit. Both are good reasons for the difference in sizes between the input and output. Pretty simple. I've run several of these pumps for years with no issues.

[Cadence]

Originally Posted by marlin driver

It's a macerator, meaning whatever goes in gets smaller before it goes out. It's also gravity flow in and under pressure on the exit. Both are good reasons for the difference in sizes between the input and output. Pretty simple. I've run several of these pumps for years with no issues.

The pressure probably helps to keep racing stripes off the hull. I would almost guess that bad results had something to do with installation, eg.
Discharge hose length or lift maybe putting the wrong things in the head. A paper towel used to dry hands?

[Sandibar]

Originally Posted by Dockhead

Actually, macerator pumps, not integral with the toilet, go between the tank and the outflow.

When used with non-macerating toilets, they ensure that the waste is chopped up before it goes overboard, which reduces the risk of clogging and makes it break down much more easily in the sea, so definitely a good thing.

Is there any evidence the macerating pump between tank and outflow has any ecological benefits? I would assume that the sludge in the tank gets mixed up and solids are already dissolved. And, why would solid human waste be worse than macerated sh*t for the marine ecology?

I will redo my septic system this spring and will get a macerating pump, if I can rationalize it with ecological benefits. Right now I'm drawn towards a more robust (apparently) diaphragm pump.

[Cadence]

Originally Posted by Sandibar

Is there any evidence the macerating pump between tank and outflow has any ecological benefits? I would assume that the sludge in the tank gets mixed up and solids are already dissolved. And, why would solid human waste be worse than macerated sh*t for the marine ecology?

I will redo my septic system this spring and will get a macerating pump, if I can rationalize it with ecological benefits. Right now I'm drawn towards a more robust (apparently) diaphragm pump.

I doubt it has anything to do with ecology, just being able to discharge efficiently. A turd is a turd.

[Sandibar]

Originally Posted by Cadence

I doubt it has anything to do with ecology, just being able to discharge efficiently. A turd is a turd.

That's what I'm thinking. I'd also assume that the, hum, product is not more solid from tank to outflow, compared from bowl to tank. I.e., what's the benefit of having a macerating pump after the tank?