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ken&ellen
01-15-2006, 09:52 AM
:eek: This post only after I have climbed under and in my waste water bay.
There is a MAC switch on the dash and a macerator spec sheet in my stack of manuals, BUT I can not find either the pump itself or the discharge valve. According to the literature the pump discharges through a 1" pipe, but I suspect that maybe it really discharges through the 3" main valve. Any Liberty owners that could shed some light? Thanks...Ken & Ellen

Jon Wehrenberg
01-15-2006, 12:45 PM
My pump is located on top of the waste holding tank, about 12 to 18" back (when looking into the compartment). It discharges through a tube that is routed through the rear bulkhead of that compartment and is routed to the passenger side at the rear. It terminates with a male hose fitting that is capped.

YMMV

I have seen macerator pumps located right in front of the holding tank but they were not on a Liberty and they may have been owner installed.

Jerry Winchester
01-15-2006, 04:53 PM
Our pump is located directly in front of the black water tank next to the dump valve for the tank. It discharges out a copper line that is plumbed thru the floor and terminates with a cap just under the bay even with the side of the coach. The hose screws on there.

I guess the good news is it is easily accessable. The bad news is I need to pull it off and unplug it after pumping the tank to the clean out at our house. Must have ingested something a little too new..:o

Wonder why Liberty would rig this up with that much suction head? There must be a reason, eh?

ken&ellen
01-16-2006, 08:34 AM
Jon, It was just as you discribed. Thanks. Now for the hose type? According to the manual for the pump it would require a 1" hose. I am guessing a marine duty similar to those used to pump out a boat. Any preferences? Ken

Jon Wehrenberg
01-16-2006, 03:08 PM
The tubing or hose can probably be almost anything. I have what looks like regular duty radiator hose (green stripe as I recall).

I really do not like how mine is set up, so if I were to have an opportunity to re-plumb the discharge hose from the macerator I would possibly hard plumb it with PVC tubing, and I would come out of the pump with a single flexible tube for ease of removal to service the pump, and go through the bulkhead into the hard PVC tubing. I would use a "Y" and route the tubing to both sides of the coach. For simplicity I would not try to go to the rear, but come out the side just forward of the drive axle on both sides. I would use a hose thread connection with a cap on each side.

I have never had a need for a macerator, but Mango proved to me the macerator provides backup for the regular dump valve so it has merit.

Jeffery Raymond
01-17-2006, 07:23 AM
Anyway, if you haven't used your macerator for awhile, you may find that it spins but doesn't pump. The fix is to put water under pressure through a hose into the pump, turn on the pump and prime it.

Then, turn off the water pressure, take the hose to the dump area, and turn it on.

No need to try to siphon the hose by mouth.

Timing is everything.

ChuckWall
01-17-2006, 08:44 PM
We have a '94 Liberty XL40 Classic Lady with the 8V92 - I think these coaches were built pretty much the same for a number of years. This is mostly for Ken but some others may have the same question. The macerator pump is located as Jon has pointed out - on the ceiling of the compartment - over the top of the holding tank - on the front of the tank you will find a discharge line - white PVC with rubber and stainless couplings - it goes across towards the rear then up to the ceiling and back towards the middle of the bus. Look with a flashlight and you will find the pump mounted to the top of the compartment and the outlet goes out over the the top of the wheel housing and into the engine compartment on the passenger side. It comes out with a standard hose fitting with a brass cap at the rear under the door where the batteries and Webasto are located. It is mounted below this door and you do not need to open the door for access but you can see where the line goes with the door to this compartment open. Mine runs but will not pump and it has been my experience with boats that these pumps are normally located at the bottom of the tank - not on top where it has to develop a lot of lift to work - I will try Jeffrey's suggestion and see if I can get it to prime. Perhaps this pump will work in this location - I've just never been successful in getting it to prime. Obviously it would be easier if the tank were completely full and the line was full also - but that was the situation when I tried it the first time. I have used a similar pump with the three inch fitting attached to pump the tank many times and they work great if you do not have a large dump available but do have access to a small sewer inlet that a garden hose will go into. The built-in pump would be very convenient if it worked. My question for Jeffrey would be if getting this thing primed the first time is the only difficulty or if it loses prime between usages and you have to fight with it every time? Relocating the pump to the bottom of the compartment would be a challenge but once done should work well.

Chuck Wall

Jeffery Raymond
01-17-2006, 09:24 PM
Our experience has been that it is necessary to reprime the pump to keep it happy...often. As with most things on the camper, lack of use dries seals and rubber gaskets. So, we wind up repriming often.

I noted last spring at a Parliament rally one of their new coaches using the macerator only at a full service site. Kind of a different way of handling waste, as all you need is a garden hose and a 4" fitting.

Now you may know more than you wanted?

lewpopp
01-17-2006, 09:28 PM
I was in need of my pump today because I could not move my coach for other reasons. Never used the pump and I hooke it to a discharge hose and away I went. I burned out near the end so I was satisfied for now. Guess I will call Camping World. Another $160 bucks down the drain, but it saved my life today.

Mine is mounted on the floor in front of the dump controls also. Very easy to replace.

MangoMike
01-17-2006, 09:31 PM
The second week I had the Mango Mothership we went to a Jimmy Buffet concert and on the way out (I should have waited until all the 4 wheelers left before proceeding) I hit a large rock surrounding the parking area and tore off the 4" PVC discharge on the bottom of the bus.

I did try to get the macerator to work, but being a NOOB I didn't realize you needed to prime it - no luck. So plan C. I went to Home Depot and bought a small electric pump with hose connections at both ends and pulled off the clean out plug on the top of the tank and dropped 4' of garden hose into the black tank to do the dirties. I keep the pump now just in case I ever need Plan C again.

Mike

lewpopp
01-18-2006, 09:45 PM
I will learn something by accident somewhere along the way.

I would believe I would not have to prime my mascerater if myne is below the black and gray tank. Am I correct?

ken&ellen
01-18-2006, 09:53 PM
Lew, I too learn something new. That is you have to prime the macerator pump?
I am hoping the " prime " on my holding tank level indicator is for that purpose otherwise I will continue to use the gravity system of dumping.

Ken

Jerry Winchester
01-18-2006, 09:55 PM
I didn't have to prime mine as the suction was pretty much flooded after I opened the valve from the black water tank to the macerator pump inlet. However, I may hook the water hose up backward thru the discharge and flush it out. I think I have an impacted turd in the inlet.:(

pognumber26
01-30-2006, 07:11 AM
And which number is the exclusive macerator pump...Was it # 100??:D

BrianE
05-09-2006, 01:06 PM
This seems like the right thread to jump into. On our 94 Liberty, the dump outlet hangs well below the bus body. Am always concerned about a knock off. I carry all the parts to fix it but that could be after a very embarrasing mess. Has anyone modified this arrangement with a clever little door in the bay door or something else that works? Thanks

Brian
'94 Liberty Classic XL

Jerry Winchester
05-09-2006, 02:52 PM
Brian,

Our '92 has an outlet that also hangs down and would appear to be an accident looking for a place to happen. So far it has never been whacked and shows no signs of ever being replaced.

If you stay away from those Jimmy Buffett concerts, bad things don't generally happen to your coach ;)

Just Plain Jeff
05-14-2006, 07:50 AM
If you don't use the macerator pump frequently it does need to be back-primed. We ran into this with our Liberty and a quick call to N. Chicago gave us that info. You back prime the pump, turn it on and when you hear 'turbulence in the tank,' (and I am not going any farther with that description), then you know you are set. Unhook the back prime hose and let 'er rip.

Apparently the macerator pump is NOT a self-priming pump, despite the label.

win42
07-18-2006, 07:35 PM
I have owned my 91 Royale nine years and have wondered what use the macerator could provide. I was quite sure it wasn't a deterent to tail gators. Mine is in the top of the black water tank and has a hose runing to the rear of engine compartment. I had always heard people that own Prevosts #@it doesn't stink and figured this is how it got into those little plastic bags.

Seriously there have been times when I'm sure, used properly hooked up to a dump site, it would help keepthe black water emptied. All campground drain hookups are higher than my gravity outlet. Some of you have had success using the maceato in this mnor? please tell me more.
It's been a lonely 9 years not knowing any oher Prevost owners.

Ray Davis
07-18-2006, 07:57 PM
I don't personally have a macerator, but I can think of some ways it would be used. Have you ever gotten home from a trip, and weren't able to dump? Like you dumped before leaving the campground, and then Junior (or was it Missus), had to use the potty before you got home?

With a macerator you can hook up a standard garden hose, and dump all the way into your house toilet, or if you have a small sewer access, you can do the same. Not being able to dump at home has been an issue for me in the past.

Obviously, you wouldn't want to use that garden hose for much else??

ray

Jerry Winchester
07-18-2006, 08:22 PM
Win 42,

Glad you are here and after a few weeks, you may decide lonely wasn't so bad afterall. :eek:

Just as Ray stated, we have a sewer cleanout right behind the hedge in the front of the house. A 20' hose will reach it and you can pump the black water tank out in short order with the macerator.

I also run into RV sewer hook-ups that are high enough that the tank doesn't fully drain or leaves the hose full. In several places where we dry camp or just have power, we use the sewer tank to garden hose adapter to drain the grey water into a convenient spot. I'm sure this is unheard of in the east, but here in flyover country, the world is our toilet, so game on.

Just Plain Jeff
07-18-2006, 08:34 PM
Ah, sooner or later the Black Tank discussion has to begin!

Wouldn't have a bus without a macerator, although on our old crummy Liberty it had to be primed every time we wanted to use it. With our new wonderful Vogue, it works every time and even chops, slices and dices better than a RONCO.

Some folks make up a 4" sewer cap with a garden hose adaptor on it for use at most parks and don't use the flex piping for the black tank. In a single waste tank bus, this is the real deal; simple, no flex hose and you can dump the tanks from the inside (given the control system) when necessary.

Slick.

Some people in Tennessee prime their macerator by turning it on and then sucking hard on the hose. I guess it works, but wouldn't recommend it to anyone.

Oh and most importantly, win42, please feel welcome to this crowd!! The old Groucho Marx remark of, "I wouldn't want to be in a club that would have me as a member," might fit, but we have lots of fun here and don't know the difference, so ignorance is bliss, I guess.

But don't go in the shower with Jerry. He is a really big guy.

Jon Wehrenberg
07-18-2006, 09:06 PM
"Some people in Tennessee prime their macerator by turning it on and then sucking hard on the hose. I guess it works, but wouldn't recommend it to anyone."

I see by that remark Lady Helen is going to need to hit you about the head again.

BTW, I was told by an acquaintance that he would empty his tank by using the macerator because the outlet was pointed out the driver's side. His thinking was it would spray into the median. He fessed up however that the first (and only) time this wizard did this he never considered the huge air flow around and behind a Prevost moving at highway speeds. It seems the contents ended up all over his new Jeep GC, in all the joints, in the vent under the windshield, etc. When he shut down for the day the results were dried all over the side of the Jeep, in the door gaskets, on the wipers, etc. Washing it must have been fun.

lewpopp
07-18-2006, 10:07 PM
When I was stuck in the middle of the yard for over a week when I had my axil problems, a macerator cam in real handy. I could have been the original cuz it burnt out after running it several minutes. I now have a shiney brand new one with led lights on it. Looks neat.

With a macerator, you can do one of the things that plumbers say cannot happen. They say poop doesn't run up hill, but it does woth one of these fellows.

Just Plain Jeff
07-19-2006, 06:58 AM
My aren't we thin-skinned. The 'guy in Tennessee,' is the chicken farmer who lives next to the now-defunct BG facility near Knoxville. (Many stories about him).

At one point there was a new fancy coach visiting there and the owners had two very large dogs. They decided to let the dogs run free while the coach was in the service department.

Before long, here came the farmer walking up the visitor's center, shotgun in hand. Helen, always trusting the best in everyone said, "Hey, that guy has a gun, what's he going to do?"

I said, "I think he is going to shoot the dogs."

Out from the sales department came two sales guys with their Hawaiian shirts on (no socks) running toward the chicken farmer.

Indeed, it was his intent to shoot at least the two dogs for getting into his chicken coop. After much heated conversation, a financial transaction occurred and the chicken farmer retreated to his home.

Of course,later in the day, I engaged the chicken farmer in conversation and it was, well, a rather interesting chat. It was his sense that too many of the coaches being brought in for service were there needlessly, and that many of the problems the owners had could be repaired with what was at hand; the macerator pump being just one of them.

He said that timing was everything.

And indeed, it is if you are attempting to prime the macerator by creating suction.

And there it is.

Jon Wehrenberg
07-19-2006, 07:57 AM
OK, I'll accept your story. I just did not want you spreading untrue tales about a fellow POG member.

I'll have you know I replaced the factory original black macerator hose with a clear one so I could monitor the oral priming process. As you said...timing is everything. Free advice: should you misjudge on the timing thing, do not swallow.

MangoMike
07-19-2006, 09:22 AM
My other black tank advice.

Do not let small excitable dogs to dance on the dash, close to the dump switch, while you're hooking up your 4" pipe.

Get the shotgun, dear.

MM

Yankee802
10-21-2008, 11:14 PM
I know nobody has posted to this thread in a long time, but I have some questions regarding my macerator. I don't know if this thing works at all, it hasn't since I bought it. The guy I bought the coach from thought it had been disconected, and maybe it has, I don't know.

First, when I hit the switch for it, I get nothing, no sound or anything. If all it required was priming, wouldn't I get at least some noise from the mac? Assuming that it hasn't been electricly disconnected, how do I prime it? Can't I just open up the grey to the mac pump and hit the switch? I assume that gravity would prime it, not the case?

3630

All the way to the right under the water pumps is the outlet for the mac pump. I can just connect a garden hose and run it wherever.

And a closeup:

3631

dalej
10-21-2008, 11:24 PM
My masorator pump quit working so I called the company and they said not to run it dry so I replaced the impeller (it was chewed up) and put a on/off switch right by the masorator pump that way when I open the black tank valve I can run the masorator pump and shut if off after the gray in empty.

The way mine was set up the switch was at the dash and when the pump was done pumping, I went to the dash and shut it off.

JIM CHALOUPKA
04-04-2009, 11:57 AM
Geoff, did you get your pump issue resolved. Yours looks to be the same as mine, a Jabsco 18590.
The Mfgr's. brochure states that after a sustained period of disuse the impeller may become stuck in the pump housing.
They provide for the shaft to extend out of the motor with a screw driver slot in the end. Turn it a couple times in a clockwise direction when looking at the slotted end. Yours looks to be pointing out, so it should be easy for you. (good engineering and design Marathon)

My pump is at arms length in a tight space over my tank with the shaft pointing away from any access. (bad design and engineering on Liberty's part)

I have an idea for a tool that should be able to turn my pump, but I need a couple dimensions.

What is the diameter of the slotted shaft and how wide is the slot?

If anyone else can come up with the dimensions I would appreciate it!

Thanks, JIM

flyu2there
04-04-2009, 06:28 PM
Geoff, did you get your pump issue resolved. Yours looks to be the same as mine, a Jabsco 18590.
The Mfgr's. brochure states that after a sustained period of disuse the impeller may become stuck in the pump housing.
They provide for the shaft to extend out of the motor with a screw driver slot in the end. Turn it a couple times in a clockwise direction when looking at the slotted end. Yours looks to be pointing out, so it should be easy for you. (good engineering and design Marathon)

My pump is at arms length in a tight space over my tank with the shaft pointing away from any access. (bad design and engineering on Liberty's part)

I have an idea for a tool that should be able to turn my pump, but I need a couple dimensions.

What is the diameter of the slotted shaft and how wide is the slot?

If anyone else can come up with the dimensions I would appreciate it!

Thanks, JIM


Mexican Speed Wrench outta do it...Channel Locks. Size don't matter.................

truk4u
04-04-2009, 09:30 PM
Jimmy C,

I thought your pump ran, but like mine, won't pick-up a prime probably due to a bad impeller!

JIM CHALOUPKA
04-04-2009, 09:56 PM
Tom, I can not feel any vibrations of it running and I can not hear it run. So I'm assuming it's not running. That's as far as I have gotten with it for now.

I can't turn the shaft with my fingers I can't "rab" it.

If I knew the dimensions I asked for I could cross drill a nut so it would fit the shaft and leaving the drill bit in the nut to engage the slot, I think I could rotate the shaft with my finger tips. As you know it is barely assessable in its location.:mad:

JIM

Jon Wehrenberg
04-05-2009, 07:50 AM
I won't comment on your spelling Jim, but will comment on the remark about it not making a noise.

Have you verified you have power to it?

When it gets power, even if it has lost the prime, the macerator on mine makes a very loud noise. Start with the basics before you start considering the more complex stuff, And if it is getting power, just reach in there and remove it so you can work on it at your workbench. When you reinstall it nothing says it has to be returned to that exact location.