4" Submersible Pump Stuck in 5" Casing with Pitless Unit

[JBW2017]

My 37 to 40 year old submersible well pump in Michigan finally gave out about a month ago and does not want to be extracted.

The well is about 35 feet deep and the casing is topped with a Merrill Mfg "Pitless Unit". I have managed to loosen the sliding mechanism in the "pitless unit" that presses the pitless fixture with O ring against the horizontal outlet that leads to the house, so that is not the problem that is preventing the removal of the pump. (Note: The Merrill people have been very helpful in providing info about the well-made unit.-- sideview diagram first photo below) There has never been any maintenance required for the well system (except a new pressure tank) since it was installed around 1977-1980. The well drilling company is out of business and the driller has moved to Florida.

The water from the well has contained a lot of iron -- enough to require an iron filter unit in front of a water conditioner -- so I would assume there is a significant build-up of deposits around the inside of the casing-- enough to not allow any movement of the submersible pump, galvanized outlet pipe, or the attached innards of the pitless unit. Since the water pressure has dropped off to around 22 PSI for the past several years, I also assume that water has been restricted from entering the pump by the buildup and may be responsible for the pump's failure.

The only opening of any size in the top plate of the pitless unit is the notch for the 220v electrical lines to the pump (second photo below). I suppose I could heat up and bend back the sides of the support plate with an oxyacetylene torch to get a look inside the casing, but the sliding mechanism of the pitless adapter would block further access and prevent any deep inspection of what is preventing the removal of the pump.

I have read about Hydrochloric acid (HCL) / muriatic acid used to eat away such iron build-ups, but my neighbor's well is only 25 feet away and I do not want to cause any problems for them.

Does anyone have any suggestions on how to extract the pump? Thanks in advance! --JB

 

[Reach4]

I have managed to loosen the sliding mechanism in the "pitless unit" that presses the pitless fixture with O ring against the horizontal outlet that leads to the house, so that is not the problem that is preventing the removal of the pump.

How do you know that the pitless is not what is holding?

Can you raise and lower the rod that the nut is on?

Do you have a model or link for that pitless adapter?

What is N in the drawing?

I presume you made a big t-handle puller with galvanized pipe that screws into the pitless. How much vertical force do you think you applied?

 

[Sponsor]

 

[JBW2017]

The threaded draw rod of the Merrill pitless adapter was turned clockwise to loosen the mechanism and caused the top of the rod to be lifted a little higher than the top of the pitless unit-- as indicated by the instructions to pull the unit. The threaded rod moves back and forth (side to side) by about 1/8th of an inch by finger touch.

Attached to the 1" NPT at the center of the pitless unit, a 5/8" forged eyebolt was inserted into the hole of a 1" NPT reducer, and chained to a length of 4" x 6" lumber over the well casing. I used an automotive floor jack to lift the wooden beam and kept that upward pressure in place for over 48 hours with no significant movement -- see first photo below.

My very first attempt at using the floor jack technique caused a 1/2 inch unwelded eyebolt to open up due to the upward force of the jack and the refusal of the well unit to budge. I had to adapt a forged 5/8 eyebolt for the second attempt.

Note: There was about 1/8" movement only at the start of the lift-- most likely the taking up of slack in the pitless unit. However, I tried to be patient with the process and did not exert a high degree of pressure on the beam, but thought I would increase it more each day.

The Merrill Mfg people suggested that I probe the mechanism with a flat piece of steel to ensure it has been released, but from the photo I provided to them, it appears to have been released due to the height of the threaded draw rod (second photo). I will do that test this afternoon after obtaining the steel bar.

Thanks

 

[JBW2017]

Sorry for the photos being 90 degrees and upside down... I tried to correct the problem without any success.

 

[Reach4]

The threaded draw rod of the Merrill pitless adapter was turned clockwise to loosen the mechanism and caused the top of the rod to be lifted a little higher than the top of the pitless unit-- as indicated by the instructions to pull the unit. The threaded rod moves back and forth (side to side) by about 1/8th of an inch by finger touch.

That is a rod... OK. In that case, I would think you would want to drive that rod downward to release the force on the side. I would put a block of wood between that rod and your hammer. Looking at that diagram, I think that block, that the rod connects to, would have to slide downward to move the block to the left, away from K.

The advantage of a T handle is that the piece cannot fall down the well if it becomes loosened.


Your alternative is going to be to dig down below the pitless, get the casing cut, remove the stuff, and get a new casing extension welded on. The new one will stick out higher, which is the way things should be today. That prevents a flood from letting water go into the well.

The new casing extension would get a new pitless. The new extension can be 5 inch, even if the lower casing is 4 inch (custom adapter would be used). That allows a trapezoidal pitless. If you stuck with a 4 inch casing, you would need a through-way pitless, such as the Merrill SMCK, which is what I have.

 

[JBW2017]

As for the diagram of the Merrill Pitless Unit, the items were not identified in the image found on Google Images. Item "N" appears to be some kind of threaded collar attached to the 5 inch casing, based on the photo of the threads at the bottom of the pitless unit below. There are two versions of the 5 inch unit made by Merrill and they could not determine which model it was-- but both work in a similar manner. (I think one is stainless steel) https://www.merrillmfg.com/shop/pitless-units-kits-and-adapters/spp-pitless-unit

 

[JBW2017]

That is a rod... OK. In that case, I would think you would want to drive that rod downward to release the force on the side. I would put a block of wood between that rod and your hammer. Looking at that diagram, I think that block, that the rod connects to, would have to slide downward to move the block to the left, away from K.

The advantage of a T handle is that the piece cannot fall down the well if it becomes loosened.


Your alternative is going to be to dig down below the pitless, get the casing cut, remove the stuff, and get a new casing extension welded on. The new one will stick out higher, which is the way things should be today. That prevents a flood from letting water go into the well.

The new casing extension would get a new pitless. The new extension can be 5 inch, even if the lower casing is 4 inch (custom adapter would be used). That allows a trapezoidal pitless. If you stuck with a 4 inch casing, you would need a through-way pitless, such as the Merrill SMCK, which is what I have.

The support plate at the top of the pitless unit prevents the internals from falling down into the casing. (The plate's diameter is larger than the inner diameter of the housing, so it rests on top edge of the pitless unit).

The sliding mechanism required a bit of study to understand how it functions, since drawing the threaded rod upwards is counter-intuitive for loosening the unit against the side of the casing and thereby releasing the pressure against the horizontal outlet below the frost line. From the diagram at the top, item "J" is a fixed distance from the top support plate and is pressed against the horizontal opening (item L) by the downward movement of the threaded draw rod (item I), which is fixed to the mechanism with the diagonal slot. So, in other words, by turning the nut so the threaded draw rod is raised higher above the support plate at the top of the unit, the light grey slotted unit in the diagram rises within the pitless unit, and retracts pressure from the side of the pitless unit.

To tap the threaded draw rod downward would actually tighten the mechanism.

I have the threaded draw rod as high as it would go, but maybe a little more WD40 and elbow grease will get the rod even higher (??). I will also use the steel bar (as suggested by Merrill) to see if the mechanism is free hanging.

Since I use the water only for household functions like boiler heat, and laundry/bathroom/kitchen utilities and use bottled water for drinking and cooking, if the submersible pump cannot be removed and the well salvaged, it might be best for me to cut my losses and have a new deeper well installed next to my home. (This one is in my driveway between the two garage door openings). According to my neighbor, there are traces of arsenic in the strata of water my well is tapped into and well drillers now have to go deeper to another aquifer for an approved source of water. Unfortunately, as a retiree on a tight budget, a new well would wipe out the funds that were to be applied to a new roof.

Anyway, I will post an update on this this when more information is learned. Thanks for your help.

 

[LLigetfa]

I would think you would want to drive that rod downward to release the force on the side.

Not from what I can see. Lowering the rod would seat the pitless, not retract it. Maybe the rod needs to raised more? I presume you took the picture prior to raising the rod.

 

[JBW2017]

FYI-- the instructions found under the cover of the Merrill pitless unit:

 

[JBW2017]

The before and after photos that show the position of the threaded draw rod:

 

[Reach4]

The threaded draw rod of the Merrill pitless adapter was turned clockwise to loosen the mechanism and caused the top of the rod to be lifted a little higher than the top of the pitless unit-- as indicated by the instructions to pull the unit.

OK. I was mistaken.

https://www.merrillmfg.com/shop/pitless-units-kits-and-adapters/sp-pitless-unit is the instructions.

https://www.merrillmfg.com/shop/pitless-units-kits-and-adapters/sp-pitless-unit

 

[JBW2017]

In the picture in #6, it looks to me as if A is a nut, and it looks like the rod itself does not turn.

Anyway, to loosen the pitless, I presume you turned the hex head CCW. That presumably raised A. In any case, I expect the rod is in tension in service. So when trying to loosen the grip, I would think the rod would move downward. That would push the big slotted piece downward and move the tee with the pins in the slot away from the gasket area. At least that is what I was picturing.

When you turned the hex thing I was thinking is a nut, what happened? Did the nut move up? Did the rod move up? Or what?

"B" in the diagram at the very top of the thread is the nut on the threaded draw rod. Following the directions in post #9 to pull, I turned the nut clockwise, which drew the threaded draw rod upwards above the support plate. This, in turn, caused the item with the diagonal slot to move upwards too.

Inside the slotted item is another unit with pins inside the slot that presses against the side of the adapter unit-- and with an O ring to seal the horizontal connection and a NPT connection to the outlet pipe from the submersible pump.

The slotted outer unit must be moved upward to press against the pins of the internal fitting to force that internal unit away from the wall of the pitless unit. Turning the nut clockwise to move the threaded draw rod higher above the support plate is what causes the upward movement of the slotted outer unit.

--JB

 

[Reach4]

Is there any sideways wiggle in the support plate D or in C?

 

[JBW2017]

OK. I was mistaken.

No problem-- I just appreciate the help from experienced hands on this forum. It took a lot of research and study to try to understand what I was blindly working . I have not read much on the internet about "pitless units" but there is a lot of info out there on "pitless adapters". It has been an education. Thanks!

 

[JBW2017]

Is there any sideways wiggle in the support plate D or in C?

C and D seem to be actually one unit welded together (from the other side). There appears to be just a little sideways movement. I used a sledge hammer to a piece of wood against the C fitting (while under tension by the floor jack) to see if there was movement or to free it, and it seemed to move within the confines of the pitless unit housing. There is not much slop between the support plate "D" and the inside opening/ledge of the housing.

 

[Reach4]

Given the wiggle, I doubt that a chemical is going to help.

I suspect more lift will be needed, but let one of the experienced people address that.

 

[JBW2017]

How much vertical force do you think you applied?

This afternoon after returning to the well, I relaxed the vertical force from the floor jack and tapped on the eyebolt that was screwed into the 1" NPT fitting on the top of the support plate. It moved about 1/16" in each direction (all of the clearance available inside the housing). I was able to loosen the nut on the threaded draw rod a little over 1 clockwise revolution that should have disengaged the pitless fitting a little more. I was unable to get the steel bar into the notch for electrical wires-- the bar was too big, so tomorrow I will make another trip to Menards for a smaller sized bar.

In terms of vertical force, I set up the floor jack again with the 4" x 6" board for leverage and gave it a little more lift than yesterday. Too much in fact--- the 4" x 6" beam broke around a knot a foot from the end of the 8 footer. (photo below). So I set it all up again with almost the same amount of vertical force, but with just 7 feet of 4" x 6" beam to work with.

As far as the threaded draw rod goes, I was able to get the rod above the top of the pitless unit by maybe 5/16 of an inch (maybe an increase of 3/16").... so there may be some movement of the unit after all. I banged on the eyebolt with a sledgehammer while it was under tension from the floor jack for about 15 minutes, but any upward movement seems very limited.

I am almost at the point of abandoning that well, sorry to say. I will give it a couple more days of effort. (Note: I will not use chemicals since I have concerns about causing a problem for my neighbor's well)

 

[Craigpump]

Before you abandon it, call in a well service company that has the knowledge & experience to work with this type of pitless adapter.

 

[JBW2017]

A recommended well services guy came out today and they will be putting in a new well. Essentially there were too many things that are questionable about the old well. Thanks for all of the comments and suggestions !

 

[Reach4]

A recommended well services guy came out today and they will be putting in a new well. Essentially there were too many things that are questionable about the old well. Thanks for all of the comments and suggestions !

I would have liked to have seen you pull harder... maybe with a steel bar rather than wood. 3500 pounds instead of 1000.