Sealand T series discharge pump

[Deleted member 117556]

Peggie,
I have taken you advice and replaced the jabsco macerator pump with the Sealand/Dometic T series pump on my Catalina 310. Read and followed the directions using 5 extra feet of 1.5 inch hose to couple with the existing discharge hose to the thru hull. Attached is some pictures of the installation. Right after I finished yesterday I was convinced that the pump was not actually emptying my holding tank (which I filled with fresh water for this exercise). Today I pumped more out and when I went to refill the tank it seemed to be almost empty or at least not full. Based on 300 GPH pump rate I figured it would take 3.5 minutes to empty my 17 gallon holding tank. The macerator emptied it in about 10 seconds and it was obvious when it was empty. Question is: how do I know when the tank is empty? With this pump there is no difference in the sound whether the tank is full or empty. If there is an obvious difference then for some reason this pump is not emptying my tank. Thanks for your help because I am puzzled and a bit frustrated with this....
bob

 

[Deleted member 117556]

One more detail Peggie. I installed this pump in the exact same location as the macerator which is about even with the top of the holding tank. This was what the instructions specified also...
bob

 

[kloudie1]

Not Peggy, but since that is a positive displacement pump, you should see/hear bubbles from the thruhull .. When the tank is empty, the pump will push air thru the hose.

 

[Peggie Hall HeadMistress]

The T-Pump is a diaphragm pump, so it does take a bit longer to empty a tank than a 12 gpm macerator pump, which is impeller driven (That "accordian" thingy in the top of the pump is the diaphragm, pushed down and pulled up each stroke by an "arm"). So I suspect it's just gonna take a bit of getting used to. However, also unlike a macerator pump, the one of the best things about the T-Pump is, it can run dry for quite a while without harm (I got distracted and let mine run for at least 10 minutes once), so it's not necessary to keep an "ear out" for the change in pitch when the tank is empty...there won't be any...the pump will just keep making the same "chunka chunka" sound till you turn it off. Just check your tank level indicator when you think it should be empty (you DO have a tank level indicator??). If not, I strongly recommend you install one! The SCAD "solo" TM™ Tank Monitors | Technologies LLC isn't expensive...the sender goes on the outside of the tank...and the amperage draw is negligible.

--Peggie

 

[Deleted member 117556]

Thank you Peggie, your reply makes a lot of sense. I do not have any tank monitors because that would make this too easy. But that is something else I need to add for sure. Good to know there is no sound difference. Will have to time it until I get a level indicator. This new pump will indeed take some getting used to but it does appear to be high quality and it is also huge compared to the macerator. Thanks again.
bob

 

[Peggie Hall HeadMistress]

Fwiw, the T-Pump on one my own boats was 11 years old and still going strong when I sold the boat. So I'd have to agree that it's very high quality.

I'm sure you already know that I'll be glad to answer any more questions if you have any.

--Peggie

 

[jaysweet]

I'm in the middle of replacing my old Jabsco, and have also considered using a diaphragm pump. My main worry is that the 2 I've looked at (the Sealand/Domestic and a Jabsco diaphragm) both have 1.5" inlet and output ports. My thru-hull is a 1", so I have to find a reducer, and I'm not having an easy time either a) understanding exactly what type of fitting to hook up to the output (it looks like a smooth, non-barbed fitting for a 1.5" hose, so what would fit this?), and also b) finding a reducer. I may also need a 90 degree elbow right at the output. Any advice? I don't ever plan to use this for sewage: just as a final rinse for the tank, after pumping out, refilling, pumping out, and then finally refilling with fresh water that I feel comfortable putting overboard.

I also bought a 1.5" ball valve that I plan to put between the tank and the pump, which seems a good idea in general. Keep it closed unless I plan to use the pump, so that sewage doesn't sit in the hose, the pump, and the hose going to the thru-hull.

 

[Deleted member 117556]

The Sealand T series actually comes with a reducer for the discharge line because this is a standard problem. They specify that you add 5 feet of 1.5 inch hose from the pump to the reducer which is what I did.

 

[Deleted member 117556]

Fwiw, the T-Pump on one my own boats was 11 years old and still going strong when I sold the boat. So I'd have to agree that it's very high quality.

I'm sure you already know that I'll be glad to answer any more questions if you have any.

--Peggie

Peggie,
Am looking to install the TM Tank monitor and wanted to ask. In your experience, does this work well over the long haul? I've been told that most tank monitors work for about a year then malfunction.
bob

 

[Peggie Hall HeadMistress]

It's the monitors that use internal senders that can fail in as little as a year. They don't really FAIL, though...the senders just get so clogged up with the animal fats in waste that they can no longer "read" anything...requiring removal and cleaning by hand with detergent and water to get them working again, which is no fun at all! Senders that go on the outside of the tank will last indefinitely as long as ALL the the installation and operation instructions are carefully followed.

--Peggie

 

[Deleted member 117556]

It's the monitors that use internal senders that can fail in as little as a year. They don't really FAIL, though...the senders just get so clogged up with the animal fats in waste that they can no longer "read" anything...requiring removal and cleaning by hand with detergent and water to get them working again, which is no fun at all! Senders that go on the outside of the tank will last indefinitely as long as ALL the the installation and operation instructions are carefully followed.

--Peggie

Thanks!

 

[jaysweet]

The Sealand T series actually comes with a reducer for the discharge line because this is a standard problem. They specify that you add 5 feet of 1.5 inch hose from the pump to the reducer which is what I did.

Thanks for the info, Bob. It's still pretty tight back there, so I would at least need a 90 degree elbow, and I don't think there's room for one. The Jabsco diaphragm pump has plenty of clearance (OTOH), but no reducer.

I tore down the pump today (which I should have done a week or two ago), and it's in really good shape with 2 exceptions. The paper gaskets are shot, and the 4 threaded brass rods that hold the 2 chambers (macerator and impeller) to the electric motor are unusable. One of the rods, in particular, is cracked 3/4 of the way through. Since I prefer not to pitch stuff in the trash, I've ordered the aftermarket stainless rods as well as the rebuild kit (even though the impeller looks practically new, after 15 years), mainly for the gaskets. This all costs $60 plus shipping. I'll probably copy the gaskets so I can cut new ones out of gasket paper next time.

Although there's some risk to just rebuilding the pump, I'll have a cutoff valve between tank and pump next time. And for now, it's around 1/3 of the price, and I'm not throwing a perfectly good motor in the trash.

 

[Deleted member 117556]

Thanks for the info, Bob. It's still pretty tight back there, so I would at least need a 90 degree elbow, and I don't think there's room for one. The Jabsco diaphragm pump has plenty of clearance (OTOH), but no reducer.

I tore down the pump today (which I should have done a week or two ago), and it's in really good shape with 2 exceptions. The paper gaskets are shot, and the 4 threaded brass rods that hold the 2 chambers (macerator and impeller) to the electric motor are unusable. One of the rods, in particular, is cracked 3/4 of the way through. Since I prefer not to pitch stuff in the trash, I've ordered the aftermarket stainless rods as well as the rebuild kit (even though the impeller looks practically new, after 15 years), mainly for the gaskets. This all costs $60 plus shipping. I'll probably copy the gaskets so I can cut new ones out of gasket paper next time.

Although there's some risk to just rebuilding the pump, I'll have a cutoff valve between tank and pump next time. And for now, it's around 1/3 of the price, and I'm not throwing a perfectly good motor in the trash.

If I had checked Jesse's blog I may have opted for the Raritan macerator pump to replace the Jabsco. Same footprint and seems to be a much better pump. Can remove it without disconnecting the outlet hose from the holding tank. Nice feature. Take a look before you decide.
bob

 

[Bob S]

I am replacing my macerator that is not working with the same pump. It’s a lot bigger than the original. Finding a location is limited. I don’t have a five foot run to the through hull. How important is that. I am using an Elegance head that I believe macerates waste before its pumped into the holding tank. Another option is to use an 1-1/2 through hull fitting and not a reducer. I can get about 3’ and will have a 90 degree bend. Am I in trouble?

 

[jaysweet]

I am replacing my macerator that is not working with the same pump. It’s a lot bigger than the original. Finding a location is limited. I don’t have a five foot run to the through hull. How important is that. I am using an Elegance head that I believe macerates waste before its pumped into the holding tank. Another option is to use an 1-1/2 through hull fitting and not a reducer. I can get about 3’ and will have a 90 degree bend. Am I in trouble?

If you have room for the bigger pump, I'd just put it in and not worry about the 5 foot thing. Enlarging the thru-hull would probably be the "proper" thing to do, but man: that's a lot of work and expense for something that's probably not a problem. If it were me, I'd just go with a length of 1.5" black reinforced hose, the reducer, then a length of black reinforced 1" hose. To be honest, this is just a gut feeling that this would work, so feel free to ignore my opinion.

I went with rebuilding the Jabsco macerator, so I have:
the holding tank,
6" of Raritan 1.5" Saniflex hose
a hose barb-to-MNPT fitting
a large PVC ball valve (female NPT on both ends) screwed to
the Jabsco macerator (cut off the hose barb, leaving the MNPT threads)
5 feet of black reinforced 1" hose
a 90 degree bronze fitting screwed into
a 1" Groco flanged thru-hull (new)

I feel pretty good about reusing the 16-year-old Jabsco macerator, which was in good shape with the exception of the paper gaskets and the bronze or brass studs, which I've now replaced with stainless.

I did have one glitch in reassembling the rebuild kit with the new stainless rods/screws. There are 4 pre-threaded holes in the pump body, which you have to use 2 of for the two long rods/screws. But about 5 degrees rotated from one pair of threaded holes, there is another pair of non-threaded holes. I screwed the rods into these by mistake (you can't see what you're doing) and broke off one of the long screws. So I had to buy another set. My stupid error, but still way under $100 for the rebuild kit and 2 sets of stainless screws.

Jay

 

[Bob S]

Thanks Jay, another issue is Beneteau uses a push button to engage the macerator. As Bob and Peggie said it is much slower than a macerator. I might want to change that out to a switch. A lot better than holding a button for ten minutes

 

[jaysweet]

Thanks Jay, another issue is Beneteau uses a push button to engage the macerator. As Bob and Peggie said it is much slower than a macerator. I might want to change that out to a switch. A lot better than holding a button for ten minutes

The old Jabsco empties our tank really quickly, or that's my memory (it hasn't worked for 5 years). We have a momentary-on switch as well. But come to think of it, I really don't ever empty a full holding tank, since we're on the Chesapeake. I mainly empty a second batch of rinse water after pumping out the crud and pumping out a first batch of rinse water. So it's probably only 1/3rd of a tank. Anyway, if and when the old Jabsco macerator goes for good, I'll probably replace it with a diaphragm pump

 

[Bob S]

We are very seldom in a discharge zone too. The macerator never worked probably from lack of use. I replaced it while doing a complete do over. Electric head, new hoses and Sealand pump. This will probably see little use but I expect it won't die from lack of use.