Pump / Vac Problems....

[dmcody]

I’d like to run this by the forum before I call a pool service for help.

Last fall I started having problems with my Hayward Pool Vac Ultra. It used to speed around the pool and do a great job cleaning the entire pool in a few hours. Now it barely crawls and has problems climbing walls and out of the hopper bottom. Coincidentally, I also sprung a small leak in my pump casing. I believe the two are related and I’m pretty sure that the pump casing O-ring or pump seal assembly is the source of the leak. I have not been able to pinpoint the exact location of the leak, but based on where the water is collecting under the pump, it is in the general area of these seals.

The pump is a 1987 ITT Marlow 1-1/2 J75EC10 pump which has worked well since I bought the house 4 years ago. In normal filtering mode, there are a few real small bubbles visible through the strainer cover. It has been like this since I bought the house. When I connect the pool vac to the system, the pump strainer chamber seems to run at about half full and I can see the water pouring into the strainer from the suction line. I don’t know if this is how it always was, but I seem to recall always seeing more air in the strainer when the vac was connected.

Could the pump leak cause the problems with the Vac? (Just realized that I need to see if the pump leaks when the vac is connected. If it leaks, the air is probably not from the source of the leak.) If the leaks are not the source of air, then I probably have a leak in the suction line. Any suggestions for testing the line?

I’ve looked online to see if I could locate a seals kit for the pump, but I have not seen the exact model number or parts breakdown that I have in the manual. My guess is that ITT Marlow is no longer around and the pump probably falls under another manufacturer’s umbrella.

Any suggestions for finding parts for this pump?

Finally, I am not a mechanic, but I know enough about pumps that I think can tear it apart and replace the seals if I can find the parts. Am I mistaken? The O-rings are easy, I’m not sure about the seal assembly.

Thanks in advance!

 

[JohnT]

You have two leaks more than likely. The leak that is causing your vacuum problem is an air leak. You won't see water except right as you turn the pump off. The most common source of such a leak would be a loose strainer basket lid, bad strainer basket lid O-ring or that same O-ring needing pool lube. You may also want to check your strainer basket drain plug and O-ring as well.

 

[dmcody]

There are no seals on the strainer basket lid. Now that you mention it, it does seem odd, but there never has been a seal. When I connect the vac to the return strainer, the hose connects to a hard PVC lid insert that sits on top of the skimmer basket. It typically has 2-3 inches of water over it so I would think that I would see a few vortex’s forming if it was sucking air. I will take a closer look tonight.

Now, the strainer basket drain plug and o-ring is new to me. The whole return inlet/strainer box is set in concrete, so I’m not sure how to check these, but again I will look tonight.

Thanks

 

[JohnT]

There are no seals on the strainer basket lid. Now that you mention it, it does seem odd, but there never has been a seal. When I connect the vac to the return strainer, the hose connects to a hard PVC lid insert that sits on top of the skimmer basket. It typically has 2-3 inches of water over it so I would think that I would see a few vortex’s forming if it was sucking air. I will take a closer look tonight.

Now, the strainer basket drain plug and o-ring is new to me. The whole return inlet/strainer box is set in concrete, so I’m not sure how to check these, but again I will look tonight.

Thanks

The strainer basket that is on the inlet of the pump.

Your comment did remind me that you might also want to check the hose fitting at the skimmer if it stands out of the water. That is a common source of air leaks.

 

[dmcody]

Ah, yes the pump strainer basket. I did check the o-ring for dry rot and notches and gave it a good lube and it didn't help. I'll probably pull the drain plugs and use pipe dope instead of the teflon tape just to make sure I'm not pulling air from the plugs.

Thanks

 

[dmcody]

relubed the o-ring on the strainer basket, redid the pump drain plugs with pipe dope and die tested the connection of the vac to the pool strainer basket and I still have the problem with the vac. On the bright side I was able to locate the o-rings and pump seal online and have placed an order to replace all of the orings and pump seal. Hopefully that solves the problem.

Still open to suggestions to solve a slow moving hayward ultra vac.

 

[JohnT]

Does your pool have a main drain or multiple skimmers?

 

[dmcody]

The pool has one combined inlet / return box. No other connections or drains from the pool.

 

[dmcody]

Update:

I changed out the pump seal, all the o-rings, and the drain plugs on the pump and when doing so, I noticed my impeller had a significant groove worn into it on the shaft - see pic. I didn't have a new impeller, so I screwed the old impeller with the new seal back onto the shaft and put it all back together to see what would happen. When I first turned the pump on after replacing everything, I only heard a hum. I popped the shaft cover off the back of the motor and gave it a turn and the pump took off. When I re-connected the impeller to the shaft, I made it hand tight as it took a little force to get it off.

Could I have just over tightened the impeller?

There was also a little wisp of smoke when it took off which I’m guessing was just the new seal rotating until it set into place. After this, the pump and the pool vac worked great for ~ 10 mins, then I noticed some moisture on the ground under the pump and pool vac slowed down again. I also notice that sometimes when I turn the pump off and then on, say for switching to backwash mode on my filter, the pump will hum for 1 sec max, and then take off.

Also, it’s not clearly shown in the picture, but when I removed the bottom/metal part of the seal, there were two washers on the shaft. I know one of them came with the seal because the new seal had one inside the metal sleeve. Should there be two washers here? The two washers look identical and I’m beginning to think that the seal has been replaced by a previous owner and they did not remove the washer, thus two washers. Of course I left the second washer in place, so maybe this is why I’m having problems.

I’m hoping I just over tightened the impeller or the second washer is causing too much stress, but could the new seal be too much for a tired (1987) motor?

Finally, I did not apply any form of lubricant on the pump seal when I placed it on the shaft. The directions didn’t indicated that it was needed, so I just cleaned the shaft as much as I could and put the seal on. Is this right thing to do?

Sorry for being long winded and thanks in advance.