Pentair max-e-glas ii letting air into system?

[dwichman]

I had some old gate valves on my pool and spa suction that went bad and started letting air into the strainer basket, filter etc. At one point it got so bad that the pump lost prime and ran dry for a while, not sure how long. I've since had the suction lines re-plumbed with new 3-way valves. No more air in the strainer basket, nice and clear in there, but my cartridge filter is filling with air and I constantly have to bleed it off out of the pressure relief valve.

Thankfully the pump still sounds okay, but I assume some of the seals have gone bad from running it dry and / or age and are now letting air into the system. I don't see any leaks. When I switch the pump off I hear some gurgling either in the filter or perhaps the pump, and see some air in the basket, but it doesn't completely drain down or lose prime.

I saw a video on youtube for disassembling the pump, impeller, seals, etc. and it looks like something I could probably take on.

Two questions:
1) Based on these symptoms do you think replacing all the seals from an overhaul/rebuild kit would fix my issue?

2) Can you tell me if my max-e-glass ii 1HP P4E6E-187L (on the pump housing) is a pre-98 which as I understand has the copper bushing, or post-98 which does not? Apparently it matters when ordering the repair kit.

Pool parts online has a matrix that suggests to me that my pump does not have the copper insert as it shows my model in the left column, and on the right column where it states copper inserts it show (-151L). I assume that means P4E6E-151L has copper insert and mine does not.

http://www.poolpartsonline.com/p-84...as-ii-dura-glas-ii-full-rated-pump-parts.aspx

Thanks for your help!

 

[JohnT]

The motor seal wouldn't be causing an air leak. Air can only leak in on the suction side of the pump, which is the strainer basket housing and the pipes that feed it.

When a pump runs dry, it canget hot enough to deform the strainer basket housing, and you can get leaks. But it would be strange to get air in the filter without having air visible in the basket. Is the water in the basket full to the lid? Any chance the skimmer weir is hanging occasional causing the pump to suck air for a short while?

 

[Citizen]

The 187 is a post 1998 model. It does not have a copper insert. The style of shaft seal you would need is the PS201

 

[dwichman]

I don't believe air is getting in between the strainer basket and the skimmer as I don't see any bubbles under the lid, it's full to the top, no air bubble. I can also bleed off a consistent amount of air from the filter bleed valve, even after bleeding all the air off until water comes out, during which I don't see any air in the basket. It's as if I can open the bleed valve just a bit to bleed off the air at the same rate is being sucked in.

When I shut the pump off I do see some air come into the basket, not a lot, and it does appear to come from the motor side of the basket as far as I can tell.

The only other strange symptom is when I switch the pump off I hear some gurgling and then a consistent hiss coming from the top of the cartridge filter near the pressure relief valve. Although the hiss sounds more internal, not like it's releasing air or water out. Is it possible the pressure relief valve is letting air into the filter when the pump is off causing this sound? Even so I don't believe this would allow air into the filter while the pump is running since it would be pressurized.

It sounds like I need to investigate the basket housing since you say the motor or impeller seals would not cause air to leak in.

 

[JohnT]

Depending on how your solar is plumbed, it can pull water out of the plumbing as it drains.

If you let the air out of your filter while the pump is running, does it get air again while the pump remains on?

 

[dwichman]

If you let the air out of your filter while the pump is running, does it get air again while the pump remains on?

Yes, continuously. For example, with the pump running I'll bleed all air out of the filter until water comes out. Then I close the bleed valve and "crack it" just slightly and a continuous small stream of air will be released. Crack it more and soon water will begin to come out. Close the valve completely and after a while (couple hours perhaps) I'll start getting air bubbles out of the pool return jets when the filter is filled with air, and I'll also begin to see the bubbles streaming through the check valve immediately after the filter. All the while I do not see any bubbles in the strainer basket.

 

[JohnT]

Any place drip a little water when the pump shuts off?

Air can't possibly get into the filter unless it comes through the basket. You could have a leak near the impeller in the basket where you wouldn't see the bubbles, but once the water goes through the pump you can't have an air leak.

 

[duraleigh]

With the pump running, the plumbing between the skimmer(s) and the impeller of the pump is low pressure and will allow air to be pulled into your system.

Air cannot be pulled into the system once you get past the impeller because the water is now high pressure........any leak after that will be water, not air.

Oops! JohnT beat me to it!

 

[dwichman]

Any place drip a little water when the pump shuts off?

I'll take a closer look at the basket housing to see if water comes out anywhere. I get some water out of the pump lid when the pump shuts off, although I do have a new pump lid and lubricated o-ring that is reasonably tight. Perhaps the water out of the pump lid is disguising the real leak.

 

[dwichman]

Well I feel a little stupid now. Turned out to be the strainer housing drain plug o-ring. Poured some water on there and the air leak stopped. Unscrewed it and the o-ring fell into 3 pieces.

I didn't think to look down there since I couldn't see the air leaking under the lid. I guess it was going under the basket and right into the pump. I didn't even know it had a drain plug.

Replaced the o-ring and no more air in the filter.

Thanks for everyone's help!