Multiple Macerator Pump Malfunctions

[Anne Castleberg]

On the H450 there are two holding tanks and two macerator pumps. Since we purchased our boat two and a half years ago we have had onging problems with the front (bow) pump/tank. Initially we had the original pump fixed numerous times. Then we replaced the original macerator pump with a better model Jabsco thinking the first pump had overheated and burned out. We still continue to experience what can best be described as an intermittent problem. The pump (this new one and the old one after we'd had it repaired) would work for a while, maybe one or two times and then - it failed. Our mechanic called Jabsco about the problem with the new pump and they said the only way the particular problem could occur, a rubber valve getting turned backwards is if we failed to open the through hull. But we are not novices and always open the thu hull. We have not had a problem with macerator pump for the master bedroom head. Any ideas, could there be a problem with the holding tank, or the through hull - our diver has checked and it is clear and unobstructed from the outside? For now, once again we are installing the spare, older model jabsco that we had on hand. But this is getting ridiculous and expensive.Any help appreciated.Anne and Grant Castleberg on Pilgrim in Santa Barbara

 

[Bill Jones]

Probably too simple, but...

You've probably done this but one frequent attribute of the Jabsco macerator pump is that it "freezes" up. You can tell if this is the case by placing a finger on the lowest part of the pump, a small screw headed fitting. If it is not spinning when the pump is in use, it is frozen. All you have to do is take a small screwdriver and free up the fitting by twisting it. Bill

 

[Peggie Hall/Head Mistress]

Where is the macerator located relative to...

The holding tank discharge port? If it's considerably higher and more than a couple of feet away, your problem may be caused by the macerator failing to prime before "frying" the impeller.The other possibility is a blocked holding tank vent...the macerator works till it pulls a vacuum, at which point it keeps pumping but can't move any waste. The vent doesn't have to be totally blocked for this to happen.

 

[Bob B]

Put in a DIFFERENT TYPE of pump

I gave up on the product you are using a year ago. I replaced the forward pump with a BELLOWS type of pump for the overboard function. While you are at it, put in a "Y" valve for your OFF-SHORE operation. If you have a standard (not vaccu flush, lavac or other systems), you might want change out the manual pump on the head to a macerator type(your option)flusher that aids heavier articles discharge into the tank. I still have the manual one. This may sound like a little bit of overkill but it works. The bellows is quieter too.

 

[George Fletcher]

Same problem - -

I had the same problem with the forward tank. I "fried" an impeller.The root cause was a bad "O" ring on the pump out deck port. The pump, being above the tank, wouldn't pull a prime with the bad "O" ring seal.Rebuilt the pump head and replaced the "O" ring. All is well in the well.