Dometic Masterflush Grinding Noise

[Desertboyz]

I don't think anything was dropped into the toilet, but the mid-bath starting making a loud grinding sound yesterday. Any ideas for a DIY remedy?

 

[Neal]

Seems to me you may have to disassemble and inspect the blade assembly.

 

[Buly]

My middle bath toilet makes rumbling noise, like the macerator is out of balance. Can’t convince myself to start taking it apart? AKA TOO Lazy

 

[Just George]

If you have a waterproof endoscope you could take a look at the grinder blade. The plumbing takes an immediate 90 degree turn towards the back of the commode and there you will find the grinder blade. This may allow you to see if there is something in it or what the issue is. As Neal has stated you most likely will need to remove the commode from the floor and disassemble to remedy.

 

[Desertboyz]

Thank you all for the suggestions. I was hoping for a miracle answer! It started so suddenly with just liquid in the bowl. The back bathroom is for #2.

 

[MapNerd]

I’ve done it several times. Young kids like to flush wipes.

It’s really easy to disassemble and not actually a terribly disgusting job. Much cleaner than any house toilet I’ve ever disassembled.

1. Disconnect water to coach
2. Turn off water pump.
3. Flush toilet once or twice to drain water (some will be left but not much)
4. Put down some old towels on the floor in front of the toilet
5. Remove the two screws holding the toilet to the floor
6. Gently slide the toilet forward a few inches so you can get access to the rear connections
7. Disconnect drain line by loosening oeticker clamp and pulling up on drain line
8. Disconnect waterline by loosening oeticker clamp and moving line over to open drain line and letting water run into drain
9. Disconnect power
10. Flip toilet onto face on towels to catch any water from bowl
11. Remove macerate by loosening Velcro strap and pulling two halves apart
12. Clear obstruction and perform steps in reverse order to reassemble.

Took me an hour the first time I did it as I went super slow. 20 minutes the second time. I bet I could do it in 15 now.

 

[Buly]

I’ve done it several times. Young kids like to flush wipes.

It’s really easy to disassemble and not actually a terribly disgusting job. Much cleaner than any house toilet I’ve ever disassembled.

1. Disconnect water to coach
2. Turn off water pump.
3. Flush toilet once or twice to drain water (some will be left but not much)
4. Put down some old towels on the floor in front of the toilet
5. Remove the two screws holding the toilet to the floor
6. Gently slide the toilet forward a few inches so you can get access to the rear connections
7. Disconnect drain line by loosening oeticker clamp and pulling up on drain line
8. Disconnect waterline by loosening oeticker clamp and moving line over to open drain line and letting water run into drain
9. Disconnect power
10. Flip toilet onto face on towels to catch any water from bowl
11. Remove macerate by loosening Velcro strap and pulling two halves apart
12. Clear obstruction and perform steps in reverse order to reassemble.

Took me an hour the first time I did it as I went super slow. 20 minutes the second time. I bet I could do it in 15 now.

Thank you John. I needed some instructions, so I know what to do and if I needed any special tools ?

 

[J&JD]

I’ve done it several times. Young kids like to flush wipes.

It’s really easy to disassemble and not actually a terribly disgusting job. Much cleaner than any house toilet I’ve ever disassembled.

1. Disconnect water to coach
2. Turn off water pump.
3. Flush toilet once or twice to drain water (some will be left but not much)
4. Put down some old towels on the floor in front of the toilet
5. Remove the two screws holding the toilet to the floor
6. Gently slide the toilet forward a few inches so you can get access to the rear connections
7. Disconnect drain line by loosening oeticker clamp and pulling up on drain line
8. Disconnect waterline by loosening oeticker clamp and moving line over to open drain line and letting water run into drain
9. Disconnect power
10. Flip toilet onto face on towels to catch any water from bowl
11. Remove macerate by loosening Velcro strap and pulling two halves apart
12. Clear obstruction and perform steps in reverse order to reassemble.

Took me an hour the first time I did it as I went super slow. 20 minutes the second time. I bet I could do it in 15 now.

@MapNerd, you didn’t glue anything together during reassembly did you? Excess glue could cause slow drainage of your tank. ???

 

[redbaron]

I too have had to deal with this with my young kids.

Often it can be resolved by first pouring a full gallon of water in the toilet so that there is plenty of liquid, and then while flushing, squeeze and release the black tube at the back of the toilet. Depending how big the object is, it should pass thru. The smallest of objects can cause the problem.

If it is too big, then @MapNerd did a great job of detailing the procedure.

 

[Desertboyz]

I was nervous a DYI wasn't possible for a CPA like me. But with the step-by-step instructions, it's possible. I was nervous when the brains behind IRV2 left! Thank you for creating RVForums.com. A class act too!