Question about what seems to be a suction side leak.

[mmcgirr]

Hi guys,

Dropping in to the pumphouse, my original intro thread and so forth is here if for some reason you need a reference: green-water-moved-topic-from-introductions-t58765.html

In any event, you can see my filter / pump setup in my sig, and I didn't realize it previously, but after watching some youtube videos and reading a whole bunch of stuff in this section of TFP, I realize that I seem to have a relatively large suction-side leak.

Here's the symptom: pump basket is "churning" - so there's a pretty decent amount of air mixing up with the water. I tried to use the shaving cream method to detect any leaks pre-basket, and post skimmer - with no luck. I've not yet tried the water on the joints method, as I'm using the hose to try and fill up the pool some more (it seems to me that the water level might be a touch low, so I'm going with the "simple" things first.)

However, while the pool is filling up some more (on 4 screws of the skimmer, my water line is probably between the 2nd and 3rd ones up), I noticed that my sand filter was "gurgling". Wanting to see what's up with that, I decided to take the multiport valve off, and very very briefly (maybe 1 second) ran the pump with the collar off, which obviously shot water onto my pants Anyway, when I put the collar back on and tightened it down, I noticed that the "churning" in the pump was much less than it has been previously. It's still churning mind you, but it's much less worse.

So, I'm asking all you wizards, is it possible for the filter (pressure side) to become vapor locked or something like that, and "cause" a greater pull than would normally occur, thus blowing air past the basket o-ring or other joints that are normally air-tight? I know nothing about hydraulics, and I've tried to read about head and suction and all that jazz in here, but honestly it might as well be greek.

Anywho, any advice on getting this churn / air gone from my pump basket would be super. I'm pretty sure that my vacuum (that I've been having a heck of a time with) would actually work if I could get this sorted / find out where the problem is.

Thanks!
-Mike-

 

[JohnT]

The air is getting in before the pump. Check that flow is clean in your skimmer with no vortex or burping. Also check your drain plug on the pump basket for tightness and an O-ring or washer. It could also be caused by a restriction in the intake lines from the pool.

 

[mmcgirr]

The skimmer shows no signs of burping or vortex, so I guess we can rule that out.

I should note (forgot to in my previous post) that it goes like thus:

skimmer->union->1.5" flex line->union valve->straight male-male section of 1.5" hardline->basket inlet.

I'm going to try the water hose trick later tonight when I have more free time to see if I can nail it down that way, and I figured it was pre-pump (based on all the other threads I've read) but the filter gurgle really has me puzzled - also, like I say, the churning got better once I popped the multi-port off and ran the pump for a bit. Does that mean anything, or am I just chasing ghosts? Note that I'm sure that it's pre-inlet, but I figured I'd ask about the filter gurgle while I was in here and see what y'all thought about that too.

Thanks!
-Mike-

 

[duraleigh]

Check the connections at the union (has to be perfectly parallel....make sure the 0-ring is seated correctly). Then check carefully that flex at each end....notorious for leaking joints.

 

[mmcgirr]

To be perfectly honest, I looked at that flex when I started up the pool, saw the abundance of pipe clamps on it, and decided that at some point this summer it's going to get ripped out and replaced with hard line.

Which reminds me, when I do replace it, should I reduce at fittings to 1.5", and use 2" hard line for better flow capability? Note that skimmer outlet and obviously pump inlet are 1.5".

Thanks!
-Mike-