I finally got everything hooked up so I can test it but I am having problems.

Either the pump is not getting primed or something else is wrong.

I have an sprinkler pump (50+ years old) that is taking water from a lake and using that for watering the lawn. 90% of the piping is new SCH40 PVC.

It's easier to explain with a picture.



The "orange" color line is the intake line starting at the lake, up the slope, then runs about 40' below grade to the pump. All the pipes are 1.5" SCH40 PVC, new pipes recently put together. The only old pipes I reused is the sloped pipe that runs to the lake, that was original and has been there for years. The other stretch of old pipe is there is a section where the 1.5" runs under a concrete slab, that was also existing and I reused the portion of the pipe under the slab.

Then on the outflow it is all new 1" SCH40 PVC pipes. No existing pipes. I ran about 30' of this 1" pipe, and in the middle I put in a 1" TEE with a 1/2" riser and a sprinkler head. At the end of the 1" pipe run I capped it.

Everything primed and solvent welded with Rain Or Shine blue glue. Waited 24 hours before pressurized.

So when it comes time to test I did this:

(1) Using a garden hose connect a hosebib with city water to a valve on the pump, turned on city water and let it full until the single sprinkler head on the outflow pipe start to run. The pump should be primed.

(2) Turned off city water, and turn on pump. The pump runs and runs but no water out of the sprinkler head.

(3) Removed the single sprinkler head, capped that riser too, turned pump on, same results, no water.

Does this mean the pump is not getting primed?

I can think of several possibilities.

First, perhaps there is a leak somewhere on the intake line. The section of pipe under the slab is a suspect. But I do not see water seeping out under the slab, doesn't mean there is no leak as the slab is over 12' wide.

The other possibility is the end of the line where it is supposed to be submerged into the lake, I am not sure that line is "IN THE LAKE", and if it is, I am not sure if it's not filled with silt or seaweed or whatnot. That line was existing and I only connected to it. You can see in the picture above where I shown some green blobs, because there is a lot of overgrown plants and weeds over 4' high and much of it with thorns, I can't see the end of the pipe, and I didn't try to cut a path to follow it because of snakes, toads and who knows what else are there.

Any suggestions what I should do next?

I repeated the process above three times and each time I am getting nothing.

If no suggestion my next step would be to cut the line that angles to the lake, that original line and pull it up and see how long it is and if it's wet at the end. May be glue a newer longer pipe and push that down the lake.



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Do you have a check valve at the inlet of the pump ? Do you have a foot valve in the lake on the end of the suction pipe ?

NC Plumber, there is no check valve on the inlet of the pump. There was one in the existing line that was crushed and damaged by the bobcat, I have since eliminated that and replumbed the line new.

I don't know if there is a "foot valve". I don't even know what a foot valve is. The stretch of pipe where it angles to the lake is existing and I simply connected to it. I think from your questions I need to cut the line and pull it up to see what's at the end.

Shut off the discharge valve at the pump. Pressurize the pump and suction pipe with your city water connection. After filling, shut the city off. Observe the pressure gauge on the pump to see if you maintain the pressure.

m&m, it's a very old pump.

I actually capped the outflow pipe. The water has no where to go.

There are three valves. One on the intake line, two on the outflow line. I closed all three.



Then I opened VALVE 1 and connected city water to it, and turned city water on. I waited a good five minutes then turned pump on.

Then I slowly open VALVE 2 and water shoots out of it full force. I then closed VALVE 1 and turned city water off, the water coming out of VALVE 2 immediately lose pressure.

I think tomorrow if I have time I will cut the line going into the lake, and pull it up. May be that line is clogged or doesn't extend far into the lake.

If I extend the line to make sure it goes into the lake, I can extend it a segment at a time, then pull it back until I see the end of the pipe wet.

Do I need to install a foot valve at the end? Or can I put in an 90 elbow to make sure the end of that line points up to avoid sucking in debris?

You will need either a foot valve or a check valve.

but since I am priming with city water shouldn't that at least cause it to work once?



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No, if there is no foot valve all you're doing is running city water into the lake.

Can I put in an elbow at the end of the intake pipe so that the foot valve points up. This is so I do not push the pipe into the mud at the bottom of the lake.

no

simply replace the removed check so the pump casing itself holds water

put the check (on the suction line, flow toward pump) as close as possible to lake, but EXPOSED for serviceability

the pump should be 'self priming' but ONLY if the casing itself is full to start with

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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

OK I put in a foot valve still makes no difference. I am not getting pressure at all at the outlet valve at the pump. I know this is not the best way to do it, but until I can get the overgrown vegetation at the edge of the lake cleared, there is not much more I can do.

Let me run it through one more time with more pictures, may be someone will spot something I missed.

This is a picture of the whole thing. From the pump all the way to the fence way in the back. The lake is beyond the fence.



Walking towards the fence you can see the concrete pad and the pipes that comes out of the bottom of it. There are three lines. The biggest one is a 1-1/2" in take line to the pump that starts at the lake.



At the fence, you can see a slope down towards the lake, and the pipe that goes into the lake.



So I cut the pipe going into the lake at the fence. Pulled it out, and I can see the last three feet or so full or green algae. It is wet so it is submerged in water.



Here is the foot valve I got from a plumbing supply store.



I connected a 45 elbow to the end of that intake line, then a short piece of pipe, a male adapter, then the foot valve.



I angled it because the pipe slopes down, and I am thinking by putting a 45 degree elbow the foot valve would be about horizontal in the lake.

I glued the pipes, waited an hour, then filled up the line with city water. then turned on the pump and wait. Nothing. Repeat, nothing, just like yesterday.

I even thought may be there is a leak or a tee at the pump, so I chipped away the concrete around the pipes.



I am out of ideas.

May be the pump is running but not working? Possible?

sum....Is the pump capacitor-start? If so, with a bad capacitor, it will hum, but it's not turning. Or it might start backwards.

Paul, is there a way to test this? If I open up the valve on the intake side, and put my hand on it should I feel suction?

I don't know anything about that pump. I am planning on replacing the pump eventually, but right now I am simply testing the lines are solid and working before they backfill the yard and put sod down.

Should I change out the pump now?

A picture of the pump.





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Sum, can you tell if the suction pipe is staying full of water after priming? Unscrew both unions, move the pump and see if the impeller is spinning when the motor is turned on. From the picture, it looks like the impeller should be turning counterclockwise when viewed from the suction side.



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steve,

I will try to take the unions apart this weekend. I think these unions have been together since 1953 so I hope they will come apart. I might not have a wrench big enough to torque it apart though.

Hit the wrench with a hammer. They'll come apart. There may not be any vanes left on the impellar, if they ran it unscreened for years. Or, there might be what's left of a fish, or frog stuck in it.

I don't have a wrench big enough for that big nut on that union. LOL.

Sum, one problem I see from your photos is that hose bib on the suction side of the pump. It looks to be pretty ancient; if it is not 100% water/air tight, the pump will not prime. It would be better to plug it and run the city water thru one of the two hose bibs on the discharge side of the pump.

Keep in mind that when you prime a pump, you are doing two things: putting water into the pump AND the suction pipe, and allowing the trapped air to escape past the inflowing water. This is going to be a slow process- you can't simply turn the hose on full tilt and be done. (We pros use a lot of tricks to speed this process up). Usually, you will be starting/stopping/filling/purging repeatedly until the pump "takes". Patience wins the day on this job.

m & m, I have several garden hose caps that I have used to cap these valves. I also tried to slowly open the valve on the outlet side as the city water was flowing to bleed out all the air. Did that multiple times and still no luck. Now it's either not getting primed (for some reason) or the pump isn't functional. There is no way to tell which one except to disconnect the pump and look inside the pump right?



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Does the city water flow eventually stop when you're trying to prime the pump ? The suction line to the foot valve should fill with water, the pump housing should fill and the discharge piping should fill and the water should stop flowing from the city supply. If so the pump is primed and is faulty.

NC Plumber,

Yes the city water eventually stop. Here are my steps.

(1) Connect a hose from the house hosebib (city water) to the intake line (suction side) valve. Turn hosebib on. I can hear city water running into the lines...

(2) When the city water stop running (or it could be just slow to the point I can't hear), I leave the city water on still and turn on the pump.

(3) I let the pump run for a bit, then I turn on the outflow side valve, and water shoots out of there, city water. It shoots out water and spurts of air, I let it go for a bit until water coming out is consistent.

(4) Then I turn off the city water...at the suction side valve, and at the house hosebib. The water coming out of the outflow valve slows to almost nothing.

I repeated this several times.

I mentioned earlier on the outflow line I had a TEE with a capped off irrigation riser. I unscrewed that riser and I can see water is full in that pipe. But that is all city water. I can tell the difference because the city water is clear, the lake water should be yellowish.

Most pumps have 1/4" tappings toward the top of the pump housing meant for pressure gauges, switches, etc. Remove a plug, clean the rust out of the port, and then fill the pump with water. Turn the pump on briefly. Water should spurt out of the port if you have a working pump.

I cut the intake pipe about 2' from the pump, turned pump on, felt the pipe with my hand. I can hear the sound of the pump echoing through the pipe, but felt very little suction force. Is it supposed to feel a strong suction like a vaccuum cleaner?

Next I will so what m & m suggested to fill with water then turn pump on and see.

Sum, there won't be a strong suction if the pump is full of air(the reason it needs to be primed).

well FINALLY, I figured it out.

Actually, the answer was already suggested by m & m and for some reason I wasn't thinking of it at that time.

"Sum, one problem I see from your photos is that hose bib on the suction side of the pump. It looks to be pretty ancient; if it is not 100% water/air tight, the pump will not prime. It would be better to plug it and run the city water thru one of the two hose bibs on the discharge side of the pump."

So last weekend, I did a bunch of things.

I cut the intake pipe downstream of the concrete pad. Slid a 1/2" pipe all the way in by about 15' to make sure there wasn't another check valve or something on the pipe under the concrete.

I then felt the suction with the pump on, not much suction. As steve said that may not mean anything if the pump is not primed.

Then cut the intake pipe upstream of the concrete pad. I was thinking may be there is a TEE under the concrete pad that leads to another dead end somewhere buried, so I trenched around the entire concrete pad for about 18" deep. Nothing!

I finally concluded the pump is not working, so I just need to take the pump apart. Before I did that I repeated the various tests and things I tried in my mind, and reread this thread. I saw what m & m posted and decided to unscrew that hose bib and cap it, in fact, I was about to unscrew all three hosebib, cap two of them, and replace the last one with a 3/4" nipple with a female hose adapter.

That's when I saw what's wrong. The packing nut of the suction side hosebib was loose...as in it wasn't screwed in at all. Hmmm...could that make a difference?

I tightened that packing nut, then turned city water on, then turned pump on, after about 10 seconds, the pump blew apart a riser pipe downstream, where I had a 1" TEE, with a 1"X3/4" bushing and a 3/4" threaded nipple capped. I purposely didn't glue that bushing in, only pushed it in tight and now it blew the bushing off.

The pump is working.

Everything seems to be in order.

The culprit was that hosebib with a loose packing nut.



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That's great news. It would have a bummer to have replaced the pump and had the same problem.

Glad to hear it. Air- a jet pumps' worst nightmare (as well as the homeowners).