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otrfun's avatar
otrfun
Explorer II
Oct 30, 2014

DIY Macerator

Purchased a marine-type, Seaflo macerator (12 VDC, 12 amps) on eBay for $56. Spent another $40-$50 to get it TT functional.

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Fabricated two attachments for the macerator input. One to empty the TT's waste tanks (using 3" RV flex hose); the other to empty a full waste tote (using 3/4" PVC pipe). The waste tote doesn't have a side valve, so gotta empty it in the horizontal position (too heavy to safely lift vertical).

Used flexible sewer couplings, various items of 3/4" PVC, and some garden hose. With 25 ft. of 5/8" garden hose on the output, it pumps about 5 GPM from the TT waste tanks up to the waste tote in the truck bed. Pumps approx. 4.5 GPM from the waste tote in the truck bed down to the waste dump at ground level.

We used to drag the full, 250++ lb. waste tote to the truck 10-15 ft. away. Then negotiate a 3-5 mph, 1/2 mi., pot-hole filled drive to the waste dump. No more :)

5 Replies

  • There's been a number of home-brew RV macerator fabrication posts. They're all similar except for the approach they take to interface/connect the 3" RV flex hose to the 1 1/2" hose/barb input of the marine-type macerator. Some cutoff the entire hose/barb (or leave it intact) and use a hose-clamp to mount the 3" RV flex hose to the outside of the entire pump housing. It works, but it tends to collect a bit of "stuff" inside the 3" RV flex hose because the opening goes from 3" to 1 1/2" abruptly---everything just hits a flat surface and tends to collect. It's even more of a problem if the 1 1/2" hose/barb is left intact inside the 3" RV flex hose.

    I found a 1 1/4" flexible sewer coupling (FSC) an almost ideal fit for the macerator's 1 1/2" hose/barb input. Also found a 2" FSC will fit inside a 3" RV flex hose almost perfectly (you'll need a small piece of PVC pipe inside the FSC to support the 3" RV flex hose clamp). Not sure if they make an FSC that tapers from 1 1/4" to 2" FSC. If they do, that would be the ideal solution. I couldn't find one, so I coupled together a 1 1/4" - 1 1/2" and 1 1/2" - 2" FSC. These two combined taper from 3" to 1 1/2" (similar to the Flojet)--with little flat surface--less chance of "stuff" collecting on the intake of the pump housing.
  • The last thing I'd want to DIY! LOL

    Thaks for the info.

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