Northstar pump lid

[DaveNJ]

I get air in the pump on low speed, seems to be ok on high. I replaced the T ring gasket in the lid. The lid doesn't fit as tight as it did when it was new. I am thinking of getting a pressure test o-ring and trying that. There is quite abit of flexing in the pump lid when switching between speeds. The cam action lid leaves no way to make it tighter.
Any experiences or suggestions would be appreciated.
thanks,
Dave

 

[mas985]

It would be more likely to get air in the pump at high speed than low because the suction is higher. It could be that there is an air leak but at high speed, the air is moved out of the basket fairly quickly while on low there is not enough flow to evacuate it. One way to tell is to run the pump on high speed for a while and see if the filter has air in it via the bleeder valve.

Besides the pump basket lid, valves are usually the source of many air leaks.

 

[JohnT]

I think you might be have a "self-sealing" leak that seals when the higher suction that exists on high speed pulls the lid down. You might be able to seal the lid on low speed by partially closing a skimmer or drain valve to increase suction.

 

[DaveNJ]

mas985, JohnT
I have to check out your suggestions. I do have a rattle noise in the multiport valve. I didn't notice a bleeder on the multiport.

I just took a quick look and I get some water from the lid switching speeds.

 

[waste]

Dave, where'd you hear about the blue pressure o-ring?

Those lids are just a poor design! What may be happening is that the pump on low speed doesn't create enough suction to fully seal the lid As anyone with a Northstar knows, they spit water when turned off - they obviously were designed to fully seal under negative pressure and don't hold when positive pressure is applied (like when the pump turns off) - perhaps on low speed, not enough negative pressure is created to fully seal the lid???

 

[DaveNJ]

I believe in the manual parts breakdown. The installation procedure stated to discard the o-ring after pressure testing.

 

[Titanium]

Off-Topic comment:

Wow ! That is the cleanest and neatest plumbing picture I have seen on this forum so far. Absolutely beautiful.

Titanium

 

[DaveNJ]

Thanks Titanium,

The pool was installed in August and very hot. We kept an outdoor frig. stocked with drinks for the install crew and bought them lunch a couple of times. They put in the SWCG and autofill for me at no charge. A couple of the guys stopped by on their day off, Sunday to check how everything was working.