Saturday, January 27, 2018

A 'Dirty' Job but Someone Has to Do It.

Home in Holiday – Tarpon Springs area

Our Vacuflush Vacuum Generator System

Unlike most motorhomes, our Black Tank system has what they call a Vacuflush Vacuum Generator System to push the toilet flushes over to the black tank.  Above is a picture of it as it sits inside a small outside compartment of our motorhome.  These are common on boats, less common on RVs.  Ours looks to have easier access than most boats do, so that is a plus.  When we bought this motorhome, I “KNEW” that some day I would have to work on this.  The duckbills (shown in a picture down below) are suppose to be replaced every few years…I don’t know if ours have ever been replaced.

A Vacuflush Vacuum System

Found this nicer picture of a similar one to ours with labels and diagram showing how it works.

Pump and Billows assembly

Above is the pump assembly…I need to replace the motor and billows.

Parts to fix it...motor, billows, gaskets, duckbills

These are the parts which I need to replace.  The motor and billows (white plastic thing) are different than what I have in ours … it is a new, upgrade version and the only way to replace it.  The motor now sits horizontal, and not at a slight angle like ours does.  The motor can sit to the right or to the left … the one in the picture up above lays to the right…I am not sure which way I am going to do ours.  The good news, this upgrade is suppose to be much quieter.  Those enlarged black things are called the duckbills.

Close up of our motor assembly

It should be as easy as this…..
  • Disconnect the wires from the motor…they have clips and this should be easy
  • Disconnect the four bolts, two shown by the white arrows, and two back behind it.  Getting to these back bolts will be a bit hard due to lack of room to work, but I am hoping they will unloosen without problems
  • Disconnect the entry and exit pipes, marked by red arrow…this is what I am not looking forward to…don’t know if there is fluid in these or not.  It could get messy… This is where the duckbills are located.

Parts Diagram

Above is a diagram of the assembly.  The only difference is that I am only suppose to have two of the number 12 part, they are called duckbills…however, I have four to replace with “if” there are four.  Once I get the pump assembly out, taking it apart and putting in the new parts should be fairly easy.  Thank goodness the RV Storage has wash stations to clean your RV…I have a feeling that once I get the assembly out, I will need to take the RV over and wash out that compartment, and definitely wash down the pump assembly before I take it apart.  And yes, I do have a new pair of gloves to use.  The parts should be in by Friday of next week…so I have another week to “dream” about this wonderful project…and how wonderful the smell will be…  I don't know smile


  1. Yup .... rubber gloves my friend and breathe through your mouth!! Good luck ... I don't envy your task.

  2. What a stinky job! Does it act like a macerator while pushing it into the tank?

    1. Yes it does, and uses less water too. And yep, it will stink...

  3. Somehow I missed this post but you are right someone has to do it. I just learned how boats with Heads and some RVs have a different type of Flush System.
    Best of Luck, wear Rubber Gloves and no wiping your forehead. LOL
    Be Safe and Enjoy!

    It's about time

    1. Well, ended up gloves were not needed...will blog about it when done, right now (Wednesday) it is all apart and getting cleaned up (lime-away type stuff)....more in a few days.


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