Roadtrek macerator failures--solutions?

[booster]

I have started the dual dump project on our 07 C190P Roadtrek. The messy stuff is done and the parts out, but this is not about the dual dump.

For a couple of reasons, I wanted to take the pump apart to look at it.

* Obviously it might need repair

* Campskunk had an article about backflushing his through the discharge hose, and I didn't understand how that would work in a positive displacement pump

* A poster on one of the boards had multiple pump failures and autopsied them, always finding water damage to the motor, which also didn't make sense to me.

Bottom line--no damage, in excellent condition--not too surprising as we are pretty careful

Campskunk was right, you can backflush back through discharge hose, either to the tanks or out the cleanout plug--very useful, I think if you drop something in the toilet. The rubber vanes will flex out of the way of the backwards water, it appears, or the pump may rotate from the water pressure.

The third item is what this all about--it is very possible, and probably even very likely, that you could get a water damaged motor. It is not the fault of macerator, but the way Roadtrek mounted it.

Nearly all pumps will have a gap between the pumping section and the motor. Nearly all will have gravity drain in that area to get rid of any seal leakage, to save the motor, and let you know to replace the seal. They often also have a slinger on the motor side of the gap to protect against a squirting seal leak.

The good news is that the Shurflo macerator has all those features.

The bad news is that Roadtrek mounts it upside down, so the drain is on the top. If you get a seal leak the housing will fill with water, and when it hits 1/2 full go right into the motor. We did not have any seal leakage, so good there. Road splash can also go in from the drain on top. We did show evidence of that, with dirt and bathtub ring up about 3/8" at the bottom of the housing , but not as high as the motor shaft, so we sneaked by there.

Here is what the pump looks like, as it mounts, hanging upside down.



You can see the drain right where the housing starts after the motor. That surface points up, as does the wiring grommet, which could also leak.

You might be able to clock the housing 180* to get the drain on the bottom, as it indexes on two ears, but I didn't try it with all the screws in and such.

You could also drill another drain on the lower section of the housing, and plug the upper one with silicone, and that would address this issue.

Here is what that section of the housing looks like, so you could even file a notch in the opposite side like the existing drain.



With that part of it taken care of, there is another part the probably is an issue more related to impeller life type failures.

By having the pumping chamber upside down, they have the impeller inlet slot on the top, instead of the bottom, where Shurflo has it, and where it really should be, I think. With it on the top, as soon as there is any air in the piping, it will get sucked into the pump and cause all the pulsing, etc that we all see. If the inlet is on the bottom, it won't pull any air until the pipe is nearly empty.

Here is the impeller area, with the inlet the slotted open area at the bottom, discharge at the top fitting. This is with the pump rightside up. You can easily see that if the inlet area is at the top, you will get air very soon.



Here is what it looks like with cover for that section in place, that defines the inlet area, which is very small. The choppers go on above this cover. If that inlet opening is at the top is will pull all air very soon.



This gets much harder to fix. If you remount the pump rightside up, or clock the pump housing, the discharge changes side, and will need to be replumbed. The longer/larger black water valve is on that side and will have be gotten around, but probably would be doable. For our dual dump this is going to make it so I may have to do a similar avoidance of valves, or move the pump to the behind the regular dump instead of in front of it. One way or another, as long as I am doing new mounts, it will be rightside up when we get done.

I don't know how much life would be gained by getting rightside up the inlet. With the lower inlet, it should pump more completely, suck less air and generally work better, but I won't know how much until I get everything done to see how it performs.

I would recommend anyone with a Roadtrek macerator to plug the old drain and put one on the bottom, that is pretty much no downside, all up.

The exception would be if Roadtrek has changed things since our 07, or if other models mount the pumps differently.

Some more pics

The motor slinger



The Shurflo parts explosion

[markopolo]

Good info

This site http://www.asap-supplies.com/marine/...or-pump-509550 shows left and right discharge pumps.





Looks like it is rotated, discharge up / discharge down.

Seems to indicate that you could rotate the fitting 180 degrees, make a new drain & plug the old drain as mentioned. Then make a stainless steel open ended "box" or bracket(s) to orient and mount the pump correct side up thus keeping the discharge port on the same side as the original upside down mounting. (port would be different height though)

possible?

[booster]

Excellent find Marko--they show the prices in pounds, so must be UK. I didn't see two sides on the Shurflo site, unless I missed it somewhere.

It is hard to tell for sure because they don't show the wiring entrance to the motor, but it looks like they have either clocked the pump head, or put the mounting bracket on the opposite side of the motor. Both would take some effort.

The right hand pump that shows the discharge low looks like it was made to hang upside down. You can see the drain hole on the top of it in the picture. They both would wind up with the discharge on the same side, high, if one was mounted with the motor up and the other with the motor down. On the left hand pump, you can't see the drain. The drain hole is on the side of the pump housing with the two screws in both of them and that would also be the inlet side.

If they are doing it just to change the sides of the discharge, they will get the same issues as Roadtrek would have by inverting the whole thing to change sides. Basically the drain and inlet on top instead of the bottom. If they are doing it so they can hang it upside down, they did good.

I did go back out and try to clock the pump head, and you can't do just that. It has two locating ears, so that works fine, but the three tapped holes for the pump would have to be redrilled and retapped. What they may have done on the pump in the picture that is inverted is to remove the two drawbolts that hold the motor together and rotate the end housing 180*. That would also turn the pump 180* and since there are only two screws it may actually be able to be rotated without other modifications, if there aren't any reference tabs or keys. The drawbolts are the ones you can see in the pic in the first post of the motor slinger.

[peteco]

I took a quick look at the installation instructions. I didn't see anything about mounting upright. It would be good to hear from Shuffle about that.

I did see they recommend flushing after each use, which I do not do very often.

I have a new dual dump setup to install but I have been waiting until I need to do it. I may be on borrowed time on my 2006 RT 210 as the pump has never been serviced and we have used it extensively over the past 4 years.

Pete
2006 Roadtrek 210P

[booster]

Shurflo is owned by Pentair now, it appears. I found this on the marine site, RV site doesn't show it.

http://www.shurflo.com/images/files/...s-3200-000.pdf

The parts explosion shows it all flipped over, with the drain and inlet on top, but it doesn't say anything about inverted mounting, just 180* turned outlet. From the wiring position, it looks like it is the mounting that is moved to the opposite side.

I think Peteco is right, time to get some information from Shurflo/Pentair, or whomever else is in on it.

Another thought would be that if they were on end and vertical like the one that Marko showed for the Pheonix Cruiser, it wouldn't matter if it was clocked, as the inlet would always be at the lowest level of the pump chamber, but not of the pipe. It would surely suck air early, though.

[markopolo]

If you contact them maybe ask about back flushing through the outlet.
Flushing may mean pumping non-waste water through via the inlet (only).

[peteco]

Here is similar discussion about pump and inlet orientation. They assume the inlet should be on the bottom.

http://gmcmotorhome.info/MOUNT.html

If the inlet is supposed to be on the bottom then that would also help get more water out of the lines. This would help winterizing, which unfortunately is presently on my mind.

Booster, I hope you can get clarification from Shurflo.

Pete
2006 Roadtrek 210P

[mlts22]

I know this is from left field, but would a FloJet or Xylem waste/macerator pump be a better fit, although the mounting is different?

[booster]

Thanks, petco, great link, it is always nice to get a kind of backup reality check on things like this. It sounds very similar to what I found, and concluded.

I am going to wait until next week to contact Shuflo, when there should be more folks there. I am very interested to hear what they have to say. My sense is that there may be two stories behind the scenes. One from engineering that says inlet and drain on bottom, and one from marketing that says it doesn't matter

I have seen quite a few right ups on the Flojet change, but they have had a lot of trouble with the guts of them. Particularly rotting off the draw bolts that hold the pump together very rapidly. I had heard that a material change to fix the issue is coming, but I don't know if it has been implemented yet.

[booster]

I was out playing with all the rest of the fit up on the dual dump, and am finding it sure would be nice to be able to mount the pump flange up to help with road clearance. Probably why the reversed one is available, but I still need an answer on that.

Our pump is over 6 years old, so I figured, no big risk, and attempted to rotate the output end of the motor, which would also rotate the pump 180*. Good news was that it was two screws so 180* was easy, no studs or pins to clear, so the brushes didn't appear to have moved out of place. Put the screws back in and hooked it up to a battery with no pump on it. It ran, but backwards, which does make sense I think (it has been a long, long time since 12v motor theory class) as the brushes are in the end it appears (wires go in right there) and turning the brushes 180* effectively flips their polarity. Hooked up backwards, it runs well, but couldn't check under load. This will be another question to ask Shurflo, when I finally manage to get a hold of someone there.

So far it looks like the dual dump will probably be able to done with pretty much off the shelf parts, which would be nice.

[booster]

I finally gave up on the Shurflo rep getting any good information to me, and I called Shurflo in California. After a bit of time I was able to get a hold of a guy that actually was familiar with the pumps, and was the one that the rep had asked questions about my inquiry, but not the right ones.

What was determined:

Shurflo does say the pumps can be mounted in any orientation, but are best if the drain and inlet are down and the discharge up to prevent seal leakage from destroying the motor, and to better empty the inlet piping. Just as suspected.

You can just clock the motor to get the 180* port model from a standard one without any loss, except warranty, and you have to reverse the wiring.

Roadtrek should be cutting off the 1" barb on the inlet since they are locating on the bigger thread behind it. Shurflo really didn't like that they aren't (weren't?).

They didn't know that Roadtrek was drilling a hole in the manual pump "freeup" cover, and didn't care for that either do to water into the motor possibilities.

I asked about flushing backwards like Campskunk described, and he was fairly dumbfounded by it (as was I when I heard about it). I told him the source was pretty reliable and that it had reportedly worked well. He said that he thought he would hook up a pump and try it, as it would sure be a good way to clear clogs if it worked without damaging anything. I hope to hear back on that.

My opinion would be that if your Roadtrek pump is upside down, not cut off, and with the manual hole uncovered, you could probably get much better life if all those things were fixed.

The easiest way to do it would be to buy the 180* port pump and just put it in without the manual knob, and run a new discharge line to the side pod. Really pretty easy, I think.

Our new 180* pump did show up, so it will be going into the new system.

[peteco]

Originally Posted by booster

Roadtrek should be cutting off the 1" barb on the inlet since they are locating on the bigger thread behind it. Shurflo really didn't like that they aren't (weren't?).

What is this 1" barb?

Pete
2006 RT210P

[booster]

Originally Posted by peteco

What is this 1" barb?

Pete
2006 RT210P

If you look at Marco's pix of the pumps on an earlier post, you can see a big thread on the inlet, with a reduced diameter barb for if you use a hose to connect the inlet. If you connect on the thread, they want you to cut off the hose connection, so you don't have the restriction. It is in the installation instructions, also.

[peteco]

OK. Here are the instructions on:

http://legacy.shurflo.com/pdf/rv/911_tr ... 566-G_.pdf

"Flange: To mount to 1-1/2” female flange, inlet barb must be cut off just before threads. Seal threads and hand tighten."

One other concern:
I am not seeing how I can rotate the impeller housing to get the internal inlet on the bottom because the outlet will be pointing the wrong direction. I suppose I could rotate the housing and then make brackets to mount the pump upright. Or get a new pump with the outlet in the other direction. But I would still have to rotate the impeller housing. Am I looking at these options correctly?

Pete
2006 Roadtrek 210P

[booster]

Originally Posted by peteco

OK. Here are the instructions on:

http://legacy.shurflo.com/pdf/rv/911_tr ... 566-G_.pdf

"Flange: To mount to 1-1/2” female flange, inlet barb must be cut off just before threads. Seal threads and hand tighten."

One other concern:
I am not seeing how I can rotate the impeller housing to get the internal inlet on the bottom because the outlet will be pointing the wrong direction. I suppose I could rotate the housing and then make brackets to mount the pump upright. Or get a new pump with the outlet in the other direction. But I would still have to rotate the impeller housing. Am I looking at these options correctly?

Pete
2006 Roadtrek 210P

There is no way you can use either pump or rotate the head, to get the inlet at the bottom, and not wind up with the discharge going in the opposite direction than it is stock. They only use one pump head, so you are stuck with that. The 180* pump just puts the mounting flange on the opposite side so you can have the pump head correct when mounted with the mounting flange up like Roadtrek does.

[peteco]

Originally Posted by booster

There is no way you can use either pump or rotate the head, to get the inlet at the bottom, and not wind up with the discharge going in the opposite direction than it is stock. They only use one pump head, so you are stuck with that. The 180* pump just puts the mounting flange on the opposite side so you can have the pump head correct when mounted with the mounting flange up like Roadtrek does.

So the only option is to rotate the head and see if there is a way to reroute the hose. I will have to look under to see if that is possible, after the rain, cold, etc is gone.

Pete
2006 Roadtrek 210P

[hdevera]

Excellent writeup. Thanks so much for the information. Macerator failure is one of my nightmares so I purchased a spare pump. I have a 2015 RT CS and will inspect how the macerator is mounted. Hopefully RT redesigned the install.

[gerrym51]

Originally Posted by hdevera

Excellent writeup. Thanks so much for the information. Macerator failure is one of my nightmares so I purchased a spare pump. I have a 2015 RT CS and will inspect how the macerator is mounted. Hopefully RT redesigned the install.

Hal, look at campskunks write up about the auxiliary clean out port on the sprinters you could probably adapt a temp hose to it

[booster]

Originally Posted by gerrym51

Hal, look at campskunks write up about the auxiliary clean out port on the sprinters you could probably adapt a temp hose to it

Peteco has a discussion going on that topic. It is difficult to do on the Chevies, but could be easier on hdevera's Sprinter, as I haven't seen one.

http://classbforum.com/phpBB2/viewtopic.php?f=9&t=3418

[bigoldbob]

Lordy, it feels like I need to sell this Roadtrek as ability to keep up with problems is getting beyond my capabilities! Phew! Thanks for all the input. BTW, due to medical condition, only has 28k on unit with 16k in first year! So, not 10 years of use. I know, sometimes nonuse is worse than heavy use for some things. Who is to know which item is most prone to problems with non use.