Hayward Super Pump sucking air and leaking despite new seals

[akom]

I've spent way too much time trying to figure this out and could use some help.

Equipment

• 800 gallon in-ground hot tub
• Hayward Super Pump (SP2615X202S), unknown age. 2" plumbing reduced to 1.5" for filter and heater.
• No unions, so can't remove housing easily (and no space to add unions).

Problem
After changing all the seals (with Jack's 327 lube) and taking the pump apart over and over, there is a persistent leak from the bottom (housing gasket area) and surging (air noise).
On low speed, pump does not stay primed.

Diagnostics

• No obvious cracks in seal plate, impeller, or housing. Housing stays filled when pump is off.
• No water behind seal plate (shaft seal is probably fine)
• Housing gasket looks good
• Strainer gasket and drain plugs do not seem to leak under pressure.
• Pressure testing different sections using an air compressor:
  • Returns lines hold pressure, no leaks (tested from pump housing inlet)
  • Pump leaks water at 10+ psi, and air at 3+ psi, audibly, from that bottom area.
• Tried using dye (turmeric), looks like color stays on the housing side of the seal plate, but still can't tell where it leaks.
• Tried polishing the seal plate (1500 grit sandpaper), no change.
• Ground down the housing nuts as they protruded about 0.5mm, no change.

Any advice appreciated.

 

[Texas Splash]

Welcome to TFP! Even though you aren't seeing anything with the naked eye, it sure seems like something is off near that bottom seal plate area. Can't help but wonder if that area didn't warp or something at some point in the past? If you post a pic of the motor ID label we can tell you how old the motor is. Let's see if @mas985 has any additional troubleshooting ideas.

 

[wireform]

You have 2 separate issues here. One is a suction side leak which starts at the pump basket cover and can go back to wherever the leak is. The cover and 2 drain plugs can be your problem so make sure they're clean and gaskets are intact and lubed. If it still sucks air then go back as mentioned before. The water leak is it's own problem and needs to be taken apart to evaluate further.

 

[mas985]

The seal and seal plate are on the pressure side of the pump so that is why you see/hear water/air coming out. As wireform points out, that is the first problem but separate from the air leak.

I would double check the installation of all the new seals and gaskets. Some are directional.

Also, look for any hairline cracks in the pump housing.

Why did you replace all of the seals and gaskets?

Did you just open the pool?

 

[akom]

Thanks for the responses. I appreciate not being alone with this project. I'll try to answer the questions.

• Yes, I just opened the pool after 5 years at this house (it was winterized and I never used it before).
• I replaced the seals because I was getting leaks (bottom) and a steady stream of air I needed to purge at the filter bleeder. (but at least it didn't surge)
• In addition to replacing the seals, I also redid a bunch of the plumbing (every threaded fitting leaked). All these are perfect now (pressure tested).
• The seal plate did warp (bolt corners seemed closer to housing, though I've never held a brand new seal plate so can't be sure). I "de-warped it" using a heat gun and a bend jig to reverse that bend and polished the surface with 1500 grit. Still leaks at the same place.
• I have double, triple checked (and then six more times) that all the seals are installed correctly.

I am thinking of trying this next:

1. Putting the old seals back in
2. Sealing the housing with BOSS silicone over the housing gasket (I read that suggestion somewhere)
3. New pump? If I wind up here, I'll be asking if I really need a 2 HP pump for this little hot tub

Here is the label:


and the motor:

 

[akom]

I missed one:

The cover gasket and drain bolts. I can't be sure that they are perfect, but they don't seem to be the point of failure during a pressure test. I've attempted to visually check for cover leaks during operation with a bright light, and didn't see any bubbles making it across the gasket... I changed the o-rings on the drain bolts as well, and they seem dry.

 

[mas985]

Once a pump warps, it is nearly impossible to fix. I would replace the pump.

 

[akom]

That's unfortunate
Sounds like I have nothing to lose then if I try the sealant on the housing gasket (or even instead of the gasket). I've seen "BOSS" brand recommended, but not the exact product. Any idea which product would be ideal in this situation? Any quality silicone caulk? I have some Ultra Grey on hand, but that's an automotive product.

 

[Oly]

That's unfortunate
Sounds like I have nothing to lose then

Frustrating situation akon but I like your style. Full replacement is one solution, keep us posted.

 

[drsipe]

The best way that I have found for finding suction side air leaks is: While the pump is running use a container to slowly pour water across each connection (trying to only cover one connection at a time), as you slowly pour the water across the leaking fitting, the air bubbles in the pump pot will disappear. This can be a slow process, I see that you have a few glued connections, some threaded connections and some valves, they could all be suspect in your search for the suction side leak. As pointed out earlier in the post, you should also check the drain plugs on the pump pot and pumep.

Good Luck and keep us informed.

 

[akom]

Thank you all! I have good news and bad news.

I employed advice above regarding using water to identify the leak.
I discovered that it doesn't suck air when I pour water under the housing (from a hose, basically maintaining a half inch of flowing water underneath.

I then rigged up the following test apparatus using an air compressor and a test plug with a schrader valve. This isolated the suction area.


After some careful listening I discovered the following crack in the bottom of the housing (smiley face at bottom of photo):


So... next steps:

1. How to fix a cracked pump housing
2. New housing?
3. New Pump?

Thanks all for getting me this far!

 

[Texas Splash]

After some careful listening I discovered the following crack in the bottom of the housing (smiley face at bottom of photo):

Heck of a catch! Very creative. Your call on the fix really. A housing repair is a Hail-Mary fix, but might work, or at least buy you some time. As far as replacements, it may be just as cost effective to get a new pump rather than purchasing a new wet end with seals and everything. As luck might have it, you could repair that wet end only to have the old motor go bad on you.

In an ideal, money-friendly world, I'd replace it all. But sometimes you have to do what's best for you and your checkbook at the time.

 

[wireform]

As Texas ^^^^^you need to know when to cut your loses. If it would be me I'd just ditch this old mess and be done with it. It may repair for an hour ,day week,month but then give up in the worst time when you neither have the time or availability and end up with a green mess.....

 

[drsipe]

I hate to give up on repairs, but if it were me, I'd bite the bullet and replace the pump assembly. You can still cannibalize the old pump and motor for future repairs.

Hayward 1HP Super Pump, Inground Pool, Single Speed, 115-230 Volt - W3SP2607X10 - INYOPools.com

Hayward Super Swimming Pool Pump - 1 HP Single Speed Pump

www.inyopools.com

 

[Oly]

Nice find, looks serious, is sudden structural failure a possibility?
800 gallons is a big hot tub, do you use it during the summer months?

 

[akom]

Thanks all, I'll give plastic welding a shot and see how that goes. I finally discovered pump unions that are about as long as slip-to-mip, so I'll finally be able to make the pump removable. I plan to do aluminum-mesh reinforced outside repair and a v-groove plastic-filled repair inside.

@Oly, I've never used this hot tub, or worked on any pool whatsoever until this project. I've never had a pool of any kind either, so I'm figuring things out as I go. I think it will be winterized in winter (Asheville, NC sometimes gets down to 0F, albeit most of winter is above freezing). Part of my plumbing redesign was to add a valve-controlled path from the blower right into the returns so I can blow out the entire system with a flick of a switch. Hope it works!

Grey valves in the photo:

 

[akom]

For anyone still following this, I made the repairs using a plastic welding kit (a glorified soldering iron I got on Amazon), using included filler material and reinforced with steel mesh on the outside. Since the included welder tips are very slanted, I used a 1/4-28 bolt as a tip to do the inside-housing work.

I was able to pressure test the vacuum side to about 20psi before the test plug flew out, but it seemed pretty airtight. Got it assembled, primed, and it purged air out of the system in under 10 seconds (which is amazing to me because I've never experienced this). Then, after 2 minutes the pump quit, as @wireform predicted. It started to sound funny, then stopped. After some poking, the big capacitor seems bad, so I'm once again awaiting the next Amazon delivery.

The story continues.

 

[Texas Splash]

After some poking, the big capacitor seems bad, so I'm once again awaiting the next Amazon delivery.

 

[wireform]

Unless it was not running and it had a loud hum when trying to start. I'm not sure the capacitor is the issue if it was running full speed and the stopped because this a "start capacitor" and its job is for starting, and then gets disconnected with centrifugal switch/force and removed from the circuit.

 

[akom]

Turns out that the pump now trips the breaker (15A) but only on low speed. Works alright on high speed, though it seems to pump too fast... I replaced both capacitors, no change. When switched to low speed, it sounds wrong (for under a minute until the breaker trips), almost as if it's fighting itself. It's still pumping at almost the same pressure as on high speed (this is a new behavior, low used to be low).

If the following diagram is even remotely relevant, I am guessing that the low speed winding is partially shorted.

Also, my filter pressure is at almost 30psi on high, on a just-rinsed filter . It used to be <10 psi on low, but I don't have low any more.

So I think I'm finally ready for a new pump. I could keep the housing and replace the motor, but replacement motors are $500 while I can get a complete cheap pump for $300. Googling suggests that pumps don't last more than a few years anyway, so it's not clear to me why I'd spend >$1000 here.

Suggestions welcome. Thanks all for your input.