Mike, I'm wondering if there is air being sucked in somewhere along the skimmer leg of your plumbing and the wye is acting as a vortex?
The piping to the bottom of your pond, being [possibly????] shorter[???], has a stronger flow and could cause air to be sucked in at the wye, from the skimmer leg??
Is the bottom piping run shorter than the other one?
"Horton"

Thanks Horton. Let me answer and describe. The pond bottom intake is twice the length of the skimmer pipe. Recall that this set-up has been fine for 3 years.

Process of elimination - Today I cleaned the leaf basket, drew down the pond enough to pump out the skimmer (no more silt than one might expect) wiggled the skimmer pipe, tried to run a snake but hit an elbow right away. Everything easy to clean cleaned. Tested all the plumbing joints for bubbles-none. Fired up the pump and skimmer was not drawing any water. I had noticed for a couple of days leaves were slow going in, emptied the net and walked away those days.

Now I am thinking of two possibilites. One is the kind of vortex problem you describe. The suction pipes from skimmer and bottom are 2". When they enter my pumphouse they become 3" (don't ask why, please but that upped my flow significantly). I have always had a feeling this might be a problem area but it has worked great all season.

Second, my skimmer pipe is buried just below the surface. Elbow at the skimmer, straight run of 2" flex pvc to an elbow into the pumphouse and the 3" transition. I noticed today, and had forgotten, the pipe from the skimmer is higher at the skimmer than at the pumphouse end-inch or two - built that way originally tho. As simple as that arrangement is, maybe a leak, slow to show itself, from a misbegotten winter experiment? The pipe corridor does get walked on quite a bit too and the pipe is only a couple of inches below the surface.

The simple is eliminated, what remains seems to be digging or dealing with a vortex. I think I understand the concept but have no idea how to deal with something like that.

I closed off the skimmer as the pump sounded like it was working too hard, streams flow nicely, but my neighbor has a northern locust tree that is next to my pond and the source of endless tiny leaves so I need the skimmer or a couple more leaf nets.

Thank you for responding. Hopefully some of this information will help focus on the problem.

Mike

I topped off my pond to within an inch of the top of the skimmer opening. For no reason I opened the skimmer ball valve. It started drawing in water. I pondered this while wiping egg from my face and it stopped.

Seems like air somewhere? Out of nowhere after all this time?

Mike

Mike, I'm no plumber and the thoughts in my first reply were just that.
It just seems to me, that due to a difference in either the pipe sizes, length of run or air being sucked in is the cause of your flow problem.
I wish a plumber would come in at this time an rescue both of us.

If no one else picks up the gauntlet, and comes up with a more specific answer, here on this forum. Why not try posting your problem over onto the Plumbing Forum, on the Home site?
Surely one of the plumber types over there could throw some light on the subject.

In the meantime,I'm going to "Call a friend" and see what he can add to the discussion.
Stay tuned!
"Horton"

Mike, whilst we wait on the friend replying.
I have a question.
The corrugated hose you used, is it the tough thick walled type or the thin sump pump type?
The sump pump type is susceptible to developing pin holes or damage from sharp pieces of stone.
"Horton"

Hi Horton - the corrugated pipe is "flex" pvc, the tough stuff that doesn't flex much.

I'll try the plumbing route following your getting a response - if necessary.

The pipe will be easy enough to dig up, but the elbow going into the pumphouse may be replaceable only through divine intervention.

Also, I haven't yet confessed that there is a ball valve only on the skimmer line, not the one from the pond bottom. Has to do with the transition from 2" to 3", space available and poor judgment (constant among the variables). That might be important to purging air? Gate valve might go in.

Fortunately, I have a second pump that will keep water aerated etc for the fish.

Looking forward to...

Thanks very much--a solution will be found
Mike

Mike. I ust re-read your second post again!
You said" I closed off the skimmer as the pump SOUNDED like it was Working too hard"

Could the problem be due to cavitation, I wonder?
Just another thought!
"H"

Here is a link that might be useful: Cavitation

Horton - this sound is highly subjective, esp because I use hearing aids and am not an authority on what is going on around me!

But, the skimmer pipe was not functioning (except that brief interlude) and I "thought" the pump sounded different, straining a bit. When I turned off the line it seemingly sounded as it always does.

I am quite familiar with cavitation around boat propellers but knew nothing about pumps until your link. I experienced the velocity and thumping last problem I had, thought it was fixed.

So, air is getting in, probably the buried skimmer line and causing a bunch of problems? Perhaps it is time to clean or change the impeller as it could be damaged from the volume of silt that gets moved through the system.

the non-skimmer intake is nearly on the bottom of the pond(I have noted that my once white leaf basket is discolored from silt, I presume).

Closing in perhaps? Continued thanks for the help.

Mike

Here is another bit of information. I opened the ball valve to the skimmer after being dormant overnight; it worked and then stopped again.

There is a clear check valve between the wye and the pump. When the skimmer line was opened, the water surged off and on through the check valve. When the skimmer line was closed, the water flow visible in the check valve seemed constant. I had this before when I turned my outflow way back with valves on the two pressure pipes. Thump, thump, surge, surge.

I will pour a 5-gallon bucket over the buried line to see if that stops the uneven flow, reveals a possible leak. Time for some digging it seems, unless some phenomenon of physics is identifed.

Mike

Just woke up from my hibernation - and I was just settling in too! Mike, I don't suspect any vortex problems at the wye....they probably would have been there when you set it up. If I understand your setup correctly you have a ball valve on each leg of the wye to be able to isolate flow. It sounds as if you've got a leak on the ball valve when it's in the open position on the skimmer side. What makes me suspect this is that your flow decreases when the skimmer is open but increases when it is closed. Try the following: close the drain valve (I'm assuming you have a valve on the drain side of the wye) and go to one or both of the points where the outlet from the pump is just going into the pond. Do you see ANY bubbles coming out? If so, you've got an air leak. Horton and I will scratch various parts of our anatomy as we work through this with you...trying to figure out what the !@#!@# is going on. (Sometimes one must talk to inanimate objects in the "Mother Tongue" in order to get them to straighten out and behave.)
---David

Hello David--I'm trying to get ready to hibernate myself--appreciate your postponing.

I'm confused by the term drain valve but let's try this:
there are two 3" pressure lines out of the pump (with ball valve on each). One line goes to the top of a stream. The other line splits - formerly discharging into another stream and into a filter pond, discharging underwater.

When installed, that pipe in the upper pond was flowing back down hill when the pump was stopped. I put on a check valve at the end of the underwater discharging pipe, and that seemed to take care of that situation. However, there always were bubbles discharged underwater into the pond.

This year I sent all the water from that pipe into the pond, increasing the flow to the upper pond. Now there are big, noisy bubbles burbling. This burst of air actually erupts at the water surface and makes quite a sound. I guess I must have an air leak. This the highest and farthest from this pump. It is like a pulse, one eruption followed quickly by another.

Seems I have always had a leak since I started pumping water if the bubbles transitioning over a couple of years to eruptions of air tell me it is a leak. Ignoring all of that - my basic approach to many problems - has not solved the problem, as usual.

Is such a leak only in the suction line or can something like this bubbling develop in the pressure line? The pipe in question comes out of a ball valve, another adventure in unplanned plumbing.
There is, and perhaps always has been, a leak in my system. Next step?

While I had a certain fluency in the "Mother Tongue" I have become especially fluent since the pond started. Hundreds of variables and I have no idea what the equation is let alone how to solve. Thank goodness for cooler heads and hibernation-delayers.

Closer?

Thanks a lot - Mike

Sorry for wakening you up Prof from your torpor, but I figured our two old sleepy heads, were as good as one wide awake one.
So maybe it isn't a "true" vortex situation, but I think we can agree, that errant air is in the mix, somewhere in Mike's plumbing problem!!??

Now we have Mike speaking in [pond] tongues or tongue tied, I'll close this tongue in cheek post and leave you to sort the problem out.LOL
Don't go back to sleep yet, UP there in Vermont!
Thanks David,
From DOWN here in Ontario,
"Horton"

Hey Horton...that's right, I am further north than you are!!!

Mike, if you're seeing air coming out any of the discharge endpoints it has be coming into the pump on the suction side. When the pump is running the pressure in the line would stop any air coming into it. The fact that you've noticed more air in recent times would seem to indicate that things are getting worse (so much for the "wait and see" repair method...I've tried it myself many, many times; never seems to work). On the suction side of the pump: you say that you have two lines coming in. One is from the bottom of the pond (that's what I refer to as the drain line) but this one is probably near-neutral with respect to pressure (as opposed to having significant suction) and probably isn't the source of an air leak since you say you've got approximately a 1" height differential. However, I suspect that the skimmer line may have a point that is significantly above the water line or close to it. So as I mentioned before...any way to shut off the bottom-of-the-pond line going into the pump so that 100% of the water going in is coming from the skimmer line? This would be the best way to isolate which line is causing the issue. Several things could be happening: 1.) You indicated change of flow actually increasing when you turned off the skimmer line ... this would possibly indicate a leak at/in/around the ball valve. 2.) Another possibility if: your skimmer gets a bit of air in the water as it falls from the skimmer baffle thingy (nice scientific term!) then that entrained-air can also cause the pump to lose suction. Or if the skimmer gest clogged with leaves so that it sucks a bit of air into the line. If your line on the skimmer side can act somewhat as a siphon then sometimes you can get an air bubble at the top of the siphon which will result in restricting water flow-- this happens if the water velocity through the siphon isn't high enough to sweep the air bubble out of that region of the siphon. I'm still betting that you've got an air leak somewhere on the skimmer line though.

Hope all this is helping. I'm glad Horton is awake!!!
---David

David - with the skimmer turned off, the burbling outlet in the upper pond no longer is discharging water. That location is at the end of one pressure pipe that now is dedicated to that pond.

I will try closing off the pond bottom pipe--get in the pond and put a cap on the line--don't laugh or ask why (now anyway). Then we will see something. Also, I will try to increase flow to upper pond pipe by ball valve adjustment on the other pipe, see what happens.

As for siphon effect, the skimmer pipe is only 4-5' long before it goes vertical toward the pump. Between the skimmer and the point where the pipe goes vertical, there is a 2-3" drop from skimmer to that point. Is that enough to cause siphoning serious enough to affect a 7500 gph pump?

More later

Mike

OK - I note that my flow over the final fallstones is respectable but not what I get when the skimmer is working. However, doesn't that indicate the drain line is clear and without air?

After my being out (not mentally) for a few hours, the situation was the same. I diverted more water to the burbler line and it burbled. I opened the skimmer ball valve and it worked for less than a minute, during which the water volume in my two streams diminished significantly. Closed the valve and the volume picked up again. I closed the valve handle in increments but no flow from the skimmer.

I can't get in the pond to close off drain line as it is lightening--altho a good crisping might clear the lines?

I noted that the intake for the drain line is about 4' in front of the skimmer but probably a little deeper on the pond bottom than the bottom of the skimmer.

I will close off the drain line when I can and check for bubbles--but that is dependent on the skimmer line suddenly working, meaning air in skimmer assembly? Or simply bad juju. I suppose the outcome will be telling.

I am grateful for your help and insights about this.

Mike

I've reread all the posts here just to make sure I haven't missed anything. The "vortex" effect that Horton was talking about is different than what I was thinking. So when the skimmer valve (having reread I now see you had stated that you only have a valve on the skimmer line) is opened do you see a "vortex" where the water is going into the skimmer line? This could be one point where air is being sucked in as Horton had indicated. There's another vortex condition related to fluidics behavior which isn't relevant here.

You say that if you close off the skimmer line valve, wait a bit and then open it the pump flow increases and then within a minute or so it then falls off. Check to see that your water level is high enough that you don't have air being entrained in the skimmer (or that you have a vortex sucking air into the skimmer drain going to the pump). for example, I will get a mini-waterfall occurring in my skimmer if the water level is too low. At that point the skimmer flap is down all the way but the pumps are pulling water out relatively fast for the amount coming in with the result that I'll have the mini-waterfall in the skimmer resulting in significant amounts of air being sucked into the pumps. Not too much of a problem with submerged pumps but much more so with external pumps. Solution is simple: add more water.

However, I suspect that you have an air leak into the skimmer line going to the pump. It may be at the valve or in the couplings on the flexible PVC portion of you line. That air is getting in is clear given that you see it coming out on the pressure side of your pump in your upper pond(s). If and when you get around to digging up that line check to see if the soil is excessively moist in any one particular area when the skimmer line is closed off.
---David
P.S. I think Horton's gone into hibernation!

Just woke up from a nice nap, with the thought that you were talking about me Prof.

After reading your last post, I concur with your diagnosis.
We now wait on Mike finding out where that air is entering his plumbing run from the skimmer.

I also thought that a vacuum could be forming somewhere in that run?
"Horton"

Gentlemen - your conclusion seems logical and supported more by this information.

I closed off the drain pipe with the skimmer valve both open and closed. No water or bubbles were noted at the pipe outlets, but I couldn't get to one of them very quickly to look. Turned the drain line back on and the skimmer tried to draw water, but just when I thought it was going to rock'n roll it stopped, then barely started (watching the weir move), stop-start-stop. When I closed the ball valve, the water volume increased in the streams.

I shut off the drain line again and ran the skimmer line alone, watching it try to work. I shut it off, turned it on hoping to clear something - no luck.

After all of that, I went back to the way it was - one line, no skimmer, water volume in streams decreasing and increasing as skimmer turned on and off.

Does it matter? The drain line goes into the straight part of the wye. The skimmer line has to be angled slightly to go into the angled leg of the wye.

But...I went to look at the pipe discharging in the upper pond and great bubbles were gone, clusters of small bubbles coming to the surface. Watching the bubbles was like watching breathing--a puff, a pause, a puff etc. I made various adjustments trying to get the big bubbles back but that didn't happen.

I have always believed that this "breathing" has gone on from the first water pumped a few years ago. I have seen it at both discharge points for this pump regardless of the flow settings.

The skimmer is always filled with water, no whirlpool, just constant. It is 29" deep, pipe draws from maybe 25"

One big change at the start of this season was to increase my pipe size from 2" to 3" on the pump intake side. The transition from 2 to 3 was made where the buried 2" drain and skimmer pipes come out of the ground in the pumphouse. I have boxed myself in with this lay-out of pipes and building. This 3" combined flow then is reduced to 2" at the volute, comes out of the pump in a 2" pipe before being split into two 3" lines again. A choke point? My water flow increased a lot but I have had a vague discomfort about it all.

So, there is some sort of nagging air problem evidenced by the bubbles at the end of pipes that for some reason took an unpleasant turn just as I was heading for winter's nap.

Perhaps this problem has been sneaking up on me a bit at a time? I don't understand why one day all is well, the next is not. I would think it would take a good air leak to stop the skimmer, but then I guess something could be cracking more and more with foot pressure on the pipe, whatever.

I'll wait before I dig until I hear more. Seems I am working on a long-standing situation here.

That's all I can send to the northern regions other than pictures.

Too old, too tired to be hoisted by my own follies
Mike

Mike, is it possible that you could swap the two hoses around and have the skimmer hose go into the straight leg of the "Y" fitting and the bottom [drain] hose go into the angled leg of the "Y"?
I don't like those so called "Y" fittings, as they are not a true "Y" really, they are more of an angled "T".
[I meant to ask you right at the start if that was the type of "Y" you were using]

As I said before, I'm no plumber, but I don't believe you get the same flow through both of those legs. I tend to think the stronger flow goes right through the straight part of the fitting? Mind you I could be full of ----, with that theory. As one would think the stronger flow would pull the other flow with as it goes?

Laguna pumps sell a true "Y" fitting, but unfortunately, it would be no value for your situation, as it only goes up to 1" or 1½" hose, I believe.

If you can swap the connections, humour me, give it a try and see what happens??

And hurry up, the snow is not too far away from any of our areas! LOL
"Horton"

Horton - when I constructed my system a few years ago, I did so with first-class tutelege but as is often the case, the uninformed will still do it wrong. We made many mistakes, some of which have come back to haunt, perhaps others lurk.

To wring the maximum gph out of my pump, careful calculations about head were made to match pump with set-up. The outcome was to split flow into two 3" pipes to meet the water flow goal. However, I used 2" pipe for the intake side figuring the pipe outlet hole in the skimmer was 2" (hole saws are illegal in PA) and the inlet to the pump was 2" (no reducers on weekends in PA).

All of the suction plumbing was set in place for a while before the pump was installed. These pipes were buried, it was early November and the pipe ends coming out of the ground were as rigid as an old lead pipe. And they were quite close to one another (inche max). Determined to see water flow, I made a huge mistake. I took those two pipes as my starting point and did all the plumbing, including siting the pump from there. And then building the pumphouse right over this spot was insult to injury.

Eventually I was informed that I should have installed 3" pipes on this side of the system as well. My 2" system was full of elbows and other fittings that didn't allow the best flow. I replaced the above-ground piping with 3" and did increase my flow a lot.

However, the original system was so cramped to begin with that it was only a miracle that we could squeeze in the new pipe and fittings. As I have said, the old 2" flex pvc is still in place from the pumphouse back to the pond and the skimmer.

To remove anything will mean removing everything. That wye has always caught my questioning eye right from the day I bought it. Everything is so tight, couplings between fittings---super-glued city in there. Mistakes compounded it seems. Yet it seemed to work OK until the other day.

I have the fish I swore I wouldn't have so I could avoid complications. I guess we are moving them into an aquarium for the winter (I do like them now) because I worry about enough water for them in winter, after my sorry winter-running experiment neither of us are inclined to go out and look after bubblers and heaters--mountain to Moses deal. Once I move them I'm thinking I will redo all the plumbing from the pond inward, even maybe adjusting the pumphouse.

Pending the final thoughts here, I expect to dig up the skimmer line and see what's what. Then we'll see.

What I don't understand, no matter how I look at it, is how and why a problem of this magnitude (ie shutting down a wholly functioning plumbing line that was fine just before) just pops up. I can't picture some giant air bubble appearing; solid clogging yes. I guess it is something within that has been present from the outset and has grown until its presence was signaled.

Winter seems a bit away here but... Wish I could try your experiment with the wye, thanks, but not until I tear it out. Simplest step first I guess. And patience, one of my non-virtues.

Keep at it--retirement is the time to keep doing wrong what you couldn't have done right before anyway.

Thank you much - Mike

Thank you Mike, and good luck with all that re-work.
I figure that when I'm making modifications or re-doing something that just wasn't to my liking, it's all part of the first job and just a learning experience.

Just like painting a bridge, is it ever really done!
Take care,
"Horton"

P.S. I dare say we will still hear some closing remarks from our esteemed colleague in the far, far north! LOL

Mike, after watching last nights U.S. Presidential debate on television, I have an idea........!

You could call "Joe the Plumber"! LOL

Sorry I don't mean to demean your problem but I just couldn't resist that one.
"Horton"

So Horton - after debating the pond and debating the debate, I realized I need to call Joe Six-Pack for a quick fix. Joe the Plumber will have to come out of the closet and declare for my candidate before I sign him on!

By the way, this home debate was neither our third debate nor our last.

I like your bridge analogy very much. In different times and places in my life I have watched the endless cycle of painting on the Thousand Island and the George Washington Bridges. Your point is well taken that starting over is really just continuing the original job. Of course, bridge painters get paid more the higher they get (hello, Joe Six-Pack?) and can actually retire.

Not having a working skimmer is not good. The small leaves are falling rapidly. I don't know how much debris on the bottom starts to endanger my fish--I am caught between needing to net the bottom (all vacuums are down) and net the pond.

I think you know from last winter's running commentary on my winter running folly that a have a bit of a sense of humor, enjoy the absurd even when turned inward, and find some part of survival in light-heartedness. Your comments in that vein are welcomed and are part of the mind-set I need to ignore this problem.

That said tho, I do have some problem with Internationalists and foreign provocateurs involved with politics in the States, our own brand of absurd as you no doubt noted in the debate. Of course there are certain domestics who shouldn't be involved either, as you may have noted. A chancy cross-roads ahead.

Pleased you haven't forgotten me anyway. I await the interpretation of my windy and semi-lucid descriptions from the Gentleman from Vermont. Then a first-draft final report followed much later, by direct connection if this is OK, by the outcome of my remedial action.

Thank you for the ideas and the humanity
Mike

OK. You got me. Why are hole saws illegal in PA? I am having these visions of a handyman creeping around after dark to create holes in places where the homeowner will have to call on his services to repair the damages or possibly a hefty woodpecker packing a drill with hole cutting attachment doing it's thing on the siding.
This whole thing about skimmers reminds me of the noise a kid with a straw makes getting the last bit out of his glass. You know, that horrible, rude sl-u-r-r-r-p-p! I have heard the same sound amplified in a swimming pool, from my cheap add-on skimmer and sometimes from my Skippy. In any case, if the water is turbulent there is likely to be substantial quantities of very small bubbles suspended in the water that can join up at a high point to make a larger bubble that can reduce or eliminate water flow through the pipe. I ran into this last night after a storm that loosened the moorings of the connecting tube from the skimmer cup to the filter to the pump. Enough air collected in the tube to float it which tipped the prefilter, let air collect in it and caused the bricks on top of it to fall off and tipped the collection cup to dump out all the debris that had collected. I was lucky enough to get there before the pump burned out. I guess I will be digging next spring to install a permanent skimmer. For now, I will be reducing the length of the connecting tube and maybe running it through the hole in a cement block..
Your problem is additional info that makes me think I still need to use a separate pump. Thank you, Mike. Sandy

Gents - I looked out this morning to see a good flow has changed to a very weak flow in my streams. I cleaned leaf baskets but they were fine, intake appears fine, skimmer is missing in action. I turned my other pump on high ($$$ for electric)and have plenty of flow to aerate for my fish.

But, I have a big and expensive pump that is slowly dying on me. Can air from one line migrate and begin to affect everything? Could this change signify it is not an air problem, at least totally?

I did mention in the middle of other comments that I have taken in a lot of silt, enough to stain my leaf basket to look like yellowed teeth. Might there be an impeller problem?

Little locust leaves are overwhelming me, sinking and floating. Stopped only be mosquito netting which, due to configuration and topograpy, makes access to the pond and scooping leaves almost impossible.

Please chip in when you can--things are getting away from me.

Sandy - hole saws are legal in pa; that was just a lame attempt at self-effacing wry humor concerning my lack of insight into pond construction (which apparently continues today).

Thanks - looking forward to some guidance.
Mike

"Might there be an impeller problem?"

That would be a good place to start to look Mike, since you said previously, that your pump was making loud noises.
Maybe cavitation was in fact a problem before and has damaged the pump impeller???!!!
Or it has become loose on the shaft?

I only wish we lived closer and I could come over and see the situation first-hand.
We don't, so this is the way we have to handle the problem, unfortunately!
"Horton"

Horton - seems we have gone full circle with cavitation! Everything is a mess now with leaves coming down and no skimmer. My second pump is providing what I think is sufficient aeration for my piscine wards.

I started digging up the skimmer line and it is much deeper than I remember. Tomorrow I will pull the pump and get at the impeller--fortunately I have the manual; unfortunately the impeller is not as easy to access as I hoped but surely do-able. A friend who helped me build the pond and who is really handy will take the helm.

At least there are two directions to work on plus cleaning the bottom of the pond. Getting closer to a resolution (said that every day).

Your sentiment of being able to walk over and check things out is much appreciated. It would be a pleasure. Perhaps you could make a youtube video (is there such a thing?)exhorting me on! Or a camera on my rig here.

Once I discover-note the positive tone-the problem, I guess why becomes the question of the day.

None of this would bother me if I didn't have the fish I swore never to have but did have the luxury of time. The fish have won me over--just wish I had their aquarium ready.

The best may be ahead.
Thanks - Mike

Hi Mike,
Couple of comments (probably just will confuse things a bit): a. you can have really great joints, glued to the hilt, etc. but if you get some frost lift in the ground at the wrong place to leverage a pipe against the joint you can open it up...just enough to suck air in. b. a ball valve can get a piece of grit/small stone it such that when you turn it you create a score/mark in the ball or the fitting such that you now have an entry for air to be sucked in. Sometimes the valve just gets loose or it gets frozen and gets a small crack in it. Either way...air gets in.

As to your pump...I'm with Horton - pull it, check your impeller. Last year I pulled mine apart at the end of the season and it'd just about worn out! It's why I like to keep a backup around. If you have a backup pump you can always drop it in line just to see if that changes things. Running fine sand through a pump doesn't help them too much :-))

I was very interested in your alternating surges that you observed. That can happen but it's rare. You have to get things "just right". Usually you see it when someone is running two pumps in parallel tied into the same line and even then they have to be near a specific point on on the pump curve for it to happen. I guess you're just lucky??? An alternative is that something is going on with the pump and it has something jammed in the impeller (or some other malady) that causes it to rev up (pump more) and slow down again and again. I guess that'd be another good reason to pull the pump apart and check it.

Also, as I believe Horton pointed out (I think, but too lazy to pan back through it to verify)...yes, two pipes same diameter but different lengths - the shorter one will draw more water through it because it will have less friction losses than the long one.

And now I'm going to go turn on the electric blanket. Horton, you don't need to keep shipping that cold air our way. Send it to Washington D.C.- they've got so much hot air down there they could use a bit of cooling off!!!
---David

I was late in seeing your latest post Prof, as I was out in the garden picking the bananas of the trees, in my shorts and tee shirt!
Get your old long johns out of storage, your gonna need 'em up there. LOL

Mike will be warm enough with all that work and digging he is going to do.
Can't wait to read about his findings!
"Hot Horton"

Hi - I have a diagnosis. I think it is the pump. It is a hefty Artesian that has always been very quiet with a very low constant hum. Now it is making noises, irregular sounds, almost grinding sounds (to my faulty ears).

I can't imagine air causing that. I could accept the sort of pulsing (this has been going on almost all season, intermittently) as air.

I cranked up the pump after having it off all night and it was delivering water not quite as it should (burbler not doing what it does), absent the skimmer intake. After maybe 3 hours the flow diminished. No matter what I did with the ball valves on the pressure lines, the flow was significantly reduced. So I closed the valves and disconnected the pump. I have a second pump that will keep the pond well aerated.

Aside from life intervening for a spell this morning, I spent a great deal of time cleaning leaves from the bottom to maintain a salubrious environment for the fish. I blew the switch in my pump-out shop vac, through misapplication I suppose, that repair men claim can't be repaired for less than a new vac. I sprang for one of those $40 hook-it-to-the-faucet "vacuums" that likes silt and not leaves, and spent much of rest of the day in the pond with a net.

I worked on the inlet (non-skimmer)that seems OK and the connections are tight. The inlet has a plastic mesh lobster cage over the end and I didn't see any evidence that leaves were entering the system.

I think the next step is to pull the pump, easily done, disassemble to the impeller and scope it out. Easier than hacking away at the skimmer line, the last step if necessary.

The suction pipes appear to be clear, the skimmer inlet pipe, as it enters the pump house and joins the wye, is at an angle due to the wye shape, the other pipe is a straight run into the pump, and with the behavior and noise of the pump, does it sound like air or a dirty or damaged pump, or a combination? Any idea how I can determine if it is a problem with the brushes?

Hard information will be forthcoming in a couple of days. But there is my speculative diagnosis and information to date for your consideration.

Thanks as always - Mike

Mike, if you are talking about brushes in the pump motor, it does not have any.
My money is on the impeller, gone wonky, worn or loose on the shaft.
"Horton"

Horton - I agree about the impeller. What do I remember? Too little. I thought there were posts in the past about brushes in pump motors, how to replace. That's where that thought came from, pretty sure elec motors had brushes at one time?

Is the impeller something that should be examined and cleaned when the pump is taken in for the winter. I think I remember that as a maintenance item. Maybe a difference between external and submersible. All hazy.

Can gone wonky, worn or loose damage the motor? Depends I suppose.

Monday is my target for the examination.

Mike

Mike, you are correct that SOME types of electric motors have brushes and a commutator [universal motors].
They are usually used in appliances, electric tools etc.

But the type that is on your pump unit is an induction centrifugal motor, and does not have carbon brushes.

Can a wobbly or worn impeller cause damage to the electric motor it's self?.......It is possible.
It could jam up and cause the electric mortor windings to overheat, weakening them and/or possibly burn them out!

But I would not worry about that at present.

As to cleaning impellers, I would suggest that, no matter if the pump is a submesible or an above ground type, the impeller should be inspected and cleaned, at the very least, once a season.
"Horton"

Hi Mike,
I haven't read all the post above but did skim them. If I had to make a guess the reason why the flow increased when the skimmer was turned off is that skimmer line has air in it and pump is sucking some of this air. I would guess that there is nothing wrong with the impeller. If you blocked off the bottom drain line the pump would than suck the air out of the skimmer line and the skimmer would work. But the problem is that there is a air leak in the skimmer line from the valve to the skimmer so the pump can't remove all the air from that line. Now I would guess that you have an air leak at the pump or the bottom drain line is clogged. The air leak at the pump could be as simple as the oring on the pump basket lid. When the pump was running with out much flow was the basket full of water or almost empty?
Mike

Well gents, the problem is solved with your good help.

It was indeed the skimmer pipe. A 2" flex pvc pipe exits the skimmer through the wall. Attached was a 2" abs 90 elbow pointing down vertically to attach to the vertical 2" abs running off at a strange angle to get to the pumphouse. A real stress point.

When I excavated near the elbow, I noticed the assembly was loose. The elbow and the pipe to the pump had separated quite a bit. Following a period of chagrin I made necessary repairs.

I know I should have dug it up first but it was a difficult task for me at present. There were so many symptoms I ran around looking at or listening to, non-systematically, that I confused the issue. Finally, the cause of the symptoms was found. Made me think of that tv show "House." I was about as curmudgeonly too.

I took the pump apart, a valuable exercise, and found it to be quite clean--smears of silt of various surfaces but no more. The impeller doesn't wobble and turns freely. Put silicon grease on all the ring gaskets, made it secure at re-assembly, put plumber's tape on the quick-releases.

I put eveything back together, hit the switch with fingers crossed and bingo--skimmer was great, flow was wonderful, bubbles in the upper pond were gone, pump was quiet--a new life until next time.

It is my feeling that this loose connection has always been loose from Day 1. All the little annoyances such as the bubbles have always been present, plus bubbles in the leaf basket that every effort could not remove completely. A poor glue job and stress=trouble.

I owe all of you a large thank you for your time, expertise, patience, and generous offers for assistance. My apology for going in circles, not listening to the correct advice up front, being lazy, and somehow making something straight-forward into something convoluted. Oh, and for disturbing various naps and hibernations. But I have enjoyed the communication, indeed.

Sincerest thanks to all wonderful ponders,
Mike

Mike great news, glad you found the problem area and did the necessary repairs.
Now we can all put our feet up and sleep the winter away.LOL
Good work!
"Horton"