Pentair Pinnacle Motor Replacement Questions

[LazyL]

Just replaced my Pentair Pinnacles Motor with a Century motor that is supposed to be a direct replacement Amazon.com: Pentair Pinnacle 1HP 342854 Replacement Motor Kit AO Smith USQ1102 w/GO-KIT-24: Garden & Outdoor . I was contemplating replacing the motor or buying a new pump. At the price of $150 for the new motor and not a lot of room to re-do the plumbing on my existing set up I went with just replacing the pump motor.

Everything seemed to go ok with the replacement but i did have a few questions once the install was complete.

1) The new motor did not have a whole in the end of the shaft to install the impeller locking screw once the impeller was threaded back on. I dont know which direction the impeller spins and if it spins the same direction of the threads it could be an issue. Is this intentional or could this be an issue?

2) When putting the diffuser back on 2 of the 3 screws locked down tight while the last screw did not. It seems tight but continues to turn so it is probably stripped. I am not sure the force exerted on the diffuser and if this is something i need to worry about?

Thanks!

 

[setsailsoon]

Laz,

I'm not an expert but I've done a lot of motor and pump work in my previous life. I'll offer my advice and call an expert to chime in. @Teald024 @Jimrahbe @Texas Splash

Here's my take on your questions:

1. Some repair kits seem to have the center locking screw omitted. Don't know why but I've seen both. If you look at the instructions it probably indicates this. Rotation direction should keep it tight. Only problem would be if there's an abrupt lock up. Not very likely. I might put a drop of lock-tite blue on the impeller shaft for added protection.

2. Check to see if the tread is damaged on the screw or the pump flange. The pump flange is usually soft metal such as cast magnesium alloy so it's probably the problem. If this is the case I'd call the supplier for a replacement. If it came this way you should at least get the part for free. Alternative solution would be to tap it to the next larger size and use a slightly larger screw. Or leave it out. Both of these options change the balance so they would only be a temporary solution until the part comes. Our experts may have different advice on this and I'd go with them if they do.

Only other advice I have is to make sure you change the pump seal and it looks like it was included with your kit. The pump seal you have probably leaked to cause your motor problem. Also, remove the 4 long bolts holding the pump together one-at-a-time. Add some anti-seize to the threaded part. This will enable you to disassemble the pump easily if the bearing ever needs replacement. It's a $20 part but often can't be done since the bolts freeze in the magnesium housing.

I hope this helps and good luck to you!

Chris

 

[LazyL]

Laz,

I'm not an expert but I've done a lot of motor and pump work in my previous life. I'll offer my advice and call an expert to chime in. @Teald024 @Jimrahbe @Texas Splash

Here's my take on your questions:

1. Some repair kits seem to have the center locking screw omitted. Don't know why but I've seen both. If you look at the instructions it probably indicates this. Rotation direction should keep it tight. Only problem would be if there's an abrupt lock up. Not very likely. I might put a drop of lock-tite blue on the impeller shaft for added protection.

2. Check to see if the tread is damaged on the screw or the pump flange. The pump flange is usually soft metal such as cast magnesium alloy so it's probably the problem. If this is the case I'd call the supplier for a replacement. If it came this way you should at least get the part for free. Alternative solution would be to tap it to the next larger size and use a slightly larger screw. Or leave it out. Both of these options change the balance so they would only be a temporary solution until the part comes. Our experts may have different advice on this and I'd go with them if they do.

Only other advice I have is to make sure you change the pump seal and it looks like it was included with your kit. The pump seal you have probably leaked to cause your motor problem. Also, remove the 4 long bolts holding the pump together one-at-a-time. Add some anti-seize to the threaded part. This will enable you to disassemble the pump easily if the bearing ever needs replacement. It's a $20 part but often can't be done since the bolts freeze in the magnesium housing.

I hope this helps and good luck to you!

Chris

Thanks for the response Chris.

I was hoping the rotation would keep the impeller tight rather than immediately spinning right off the threads. So, sounds like i may be good on that question.

I am replacing the pump because it was the original that was installed with the pool. It worked fine, however, had gotten extremely loud. I am actually surprised is still ran since it practically fell apart as I was removing it.

The diffuser screws, go directly into the seal bracket so I am guessing that is where it is stripped. I could replace the bracket but then i am starting to get into new pump $$ defeating my reasons for just replacing the motor. Sounds like that may be what needs to be done in order to have a properly functioning pump.

 

[setsailsoon]

Laz,

You're correct on the seal plate. You can find them online but they're around $50... I would expect our experts would advise you just bite the bullet on a pump. The noise you had was very likely the bearing which is in the front of the motor. Old pump motors almost always have seized bolts that hold the pump flange on. You can drill that out and replace but this gets way beyond a normal DIY effort. So a new pump is probably the right answer. Whatever you do I'd definitely lube the 4 long bolts as I described in the first post. This way in 5-10 years when the bearing fails you'll be able to replace the $20 bearing fairly easily.

Good luck and keep us posted!

Chris

 

[LazyL]

Well, called the pool company that installed my pool and they have a used seal plate attached to an old motor they are willing to give me. So, might be back in business.

Another thing I realized that may be incorrect is I added some of the silicone lube that came with GO kit to assist in installing the motor shaft seal. the instruction made it sound like this was ok but after an online search it sounds like you shouldnt use any lubricant. I wore gloves in order to not touch the ceramic sections with my hands. Looks like i have to remove them again anyway so i can try to wipe the lubricant off.

The four longer bolts actually came off with no problem. I had some difficulty removing the old motor bolts. I do like your suggestion of adding the anti-seize.

 

[setsailsoon]

Good for you! Sounds like your a tinkerer like me. Definitely do remove the silicone. Those ceramic mechanical seals do not like lube. Sometimes I've used soapy water but preferred way is nothing but a clean assembly or a little water. If you have some Permatex anti-seize laying around in your shop it works great for the motor bolts. The long motor bolts work fine for about a year. But they are steel and the flange is usually a cast magnesium alloy. Perfect corrosion cell. After a couple of years at least one will twist off. Then the fun begins.

Glad to see you're getting things your way on this job! You should be proud. Cheap DIY solutions are always a good thing.

Chris