Pump Leaking at PVC union

[HouTX]

I noticed that my pump was loud and making a rattling sound (not from the motor). I found a fine spray of water shooting out of it where the PVC union is (see picture). I unscrewed it (using strap wrench) but found no gasket inside, so I hand tightened it back. Pump is off at the moment as I am cleaning the salt cell. If the leak still exists, how do I fix this?

 

[MJF54]

Usually when a union leaks it is a drip or trickle. That appears to be spraying. I would open the union again and look for a hairline crack or pinhole in both sides of the fitting.

If there is a beveled section where the union fits together it will not require a gasket. This is the most common PVC fitting. If it is two flat surfaces mating you could cut a gasket from some rubber gasket material and give that a try.

You may also find that there is a groove in the bottom piece of the union. If that groove is there, you are missing an o-ring.

If you find or make a gasket, make sure to use some waterproof grease on it.

GoodLuck!

 

[tucsontico]

I believe the lack of a gasket doesn't mean it won't seal. In fact, if it required a gasket and it was missing the entire union would be pouring out water, not just a single stream. When you removed the union nut did you notice any cracks on the male threads on the pump side? The stream of water in the pic looks like a small crack has occurred under the union nut causing that thin spray. Before turning on your pump, remove the nut again and carefully examine the threads on both halves of the union. Because it is a black PVC it may very difficult to detect a hairline crack. If you cannot locate any cracks, reinstall the union and turn on the pump. If the spray is in the exact same location, I'll bet you have a hairline crack or damaged threads on the pump side of the union. Unfortunately, I don't know of a good way to permanently repair that!

 

[HouTX]

It gets worse....it is a pin hole leak at the metal base on the pump itself just below the screw on union (marked in yellow on the picture). Has anyone had any success repairing this type of leak or anything I can try ?

 

[Rossterman]

The cases are plastic and the leak is likely coming from the mating surface of the pump case to backing plate mating surface. You can try tightening the bolts but I Have found it is typically caused by the o-ring getting hard and brittle. Part is pretty cheap (relative to buying a new pump). I've fixed 2 of my 3 jandy stealth pumps that had similar leaks. Seems like ~ 10 years and they start leaking. Normally I replace the seal when I have them apart to prevent any issues down the road.

 

[HouTX]

It is not where the bolts attach to the motor. This is on the "collar" itself where the pvc pipe attached to the pump just below the threads.

 

[Rossterman]

If the case is cracked at the transition from the case to the discharge flange (where collar nut screws on) there is likely some binding on the piping as well,that you will want to fix at some point. You could try gluing it from the inside using PVC cement once you have the volute case apart. Gluing from outside might work but more likely to secure a permanent fix sealing it on the pressure side. Some plastics can be welded so might want to try that approach first as a more robust repair. Automotive body shops will typically weld plastic so might want to swing it by one once you have it apart for them to look at it.

IIRC the material is a fiber reinforced plastic that should be weldable.

 

[HouTX]

I just spoke to a repair technician. He suggested that with a 9 year old pump with a rebuilt motor and a pinhole leak in the pump body and a rattle, it is best to replace the pump and he recommended a Hayward Super 2. I will start a new thread for advice and your suggestions are appreciated.