Macerator pump will not turn on

Anyone ever have an issue with the macerator pump not turning on?  What was the issue? 

The motor can develop a "dead" spot,  when,  if the motor stops on that spot,  will not start again, unless you turn the motor from the outside with a straight slot screwdriver.  You can see the slot on the end of your macerator.
Turn it with the macerator off, and then turn it on.   
If this doesn't work, it could be a dead macerator,  or maybe a fuse.
Our's actually shorted out,  and got hot to the touch.   So try feeling it.  If so, it's toast.

Our first macerator, the original one, one of the assembling long brass bolts broke and fell away, somehow had lodged itself on the blades (bending one badly) so when trying to free the motor with a screwdriver, it didn't budge.
CLICK HERE FOR MANY PICTURES OF THE REPLACEMENT WHICH INCLUDES THE ORIGINAL WITH BROKEN BOLT.

Our first macerator, the original one, one of the assembling long brass bolts broke and fell away, somehow had lodged itself on the blades (bending one badly) so when trying to free the motor with a screwdriver, it didn't budge.
CLICK HERE FOR MANY PICTURES OF THE REPLACEMENT WHICH INCLUDES THE ORIGINAL WITH BROKEN BOLT.

Ron - slightly off topic, but do you have pictures of how your pump is mounted on the coach?  I want to compare against my Jabsco pump installation.  Also, how is the pump attached to the waste line if the brass bolts were concealed.

On topic - one of the best ways to check on a motor not running is to use a multimeter and measure the voltage at the pump when the switch is on.  That would be the start of tracing things.

Quote from: Ron Dittmer on April 14, 2025, 11:19:47 pm

Our first macerator, the original one, one of the assembling long brass bolts broke and fell away, somehow had lodged itself on the blades (bending one badly) so when trying to free the motor with a screwdriver, it didn't budge.
CLICK HERE FOR MANY PICTURES OF THE REPLACEMENT WHICH INCLUDES THE ORIGINAL WITH BROKEN BOLT.

Ron - slightly off topic, but do you have pictures of how your pump is mounted on the coach?  I want to compare against my Jabsco pump installation.  Also, how is the pump attached to the waste line if the brass bolts were concealed.

On topic - one of the best ways to check on a motor not running is to use a multimeter and measure the voltage at the pump when the switch is on.  That would be the start of tracing things.

In reverse order.....

Follow the red and black wires from the macerator.  As shown, about 12" or so, there are single pin connectors to unplug the macerator and check voltage.  In our rig macerator wiring, the colors are backwards.


About our first generation macerator.  It mounts to the motorhome waste piping, nearly identical to this, but our older design has a strap/hose-clamp to attach the macerator on to the spade-adapter.  It does NOT bolt on like this one.

Our 1st-generation is not as good as current-day because the bolts today are on the outside as seen here.  Given the age of our rig, I don't like disturbing more than necessary.  I also found it very easy to replace the pump and be done.

Quote:

Follow the red and black wires from the macerator.  As shown, about 12" or so, there are single pin connectors to unplug the macerator and check voltage.  In our rig macerator wiring, the colors are backwards.

Ditto on the 2007 Phoenix Cruiser we owned earlier.   The red/black relationship was reversed

Of course,  I didn't realize that until after methodically lacing the wire connections, sealing the harness, securing the wiring corridor and reinstalling the motor only to have the test run reveal the motor ran backwards.

I was reminded. There is the right way  There is the wrong way. And, there is the Army way.

Ditto on the 2007 Phoenix Cruiser we owned earlier.   The red/black relationship was reversed.  Of course,  I didn't realize that until after methodically lacing the wire connections, sealing the harness, securing the wiring corridor and reinstalling the motor only to have the test run reveal the motor ran backwards.

That was my experience as well.

I got the job completed, looking pretty, but my test was a total failure.  Everything working, lots of noise, but nothing coming out the discharge hose.  It took me some time to figure out that the motor was running backwards.

orange/red wire = ground
black wire = power

I wonder if the "color flip" is only on the 2007 model year.

When changing macerators, make note of this possibility on your rig.  Pay attention when disconnecting the old pump wiring colors.  In my 2007, it's red-to-black, black-to-red.

Thanks for the pictures Ron.  I think that ours mounts similarly with the tabs on the pump that lock onto posts on the pipe with a 10 deg turn of the pump body.  The Jabsco doesn't show those tabs as even an option, so it helps to see yours.

With regards to pump rotation, I'd recommend that folks connect the wiring and have someone bump the power to the pump to check rotation.  Just watch your fingers.  The impeller should rotate towards the discharge port.  Easier to check rotation before sealing it up.  But as Ron found out, the wrong rotation won't hurt anything; it just won't pump anything.

The wires are backwards on my 2010 as well.


Larry

> The wires are backwards on my 2010 as well.

I don't think they are backward.

Automotive wiring colors are:
Black is negative -12v
Red & Yellow      +12v