RichToyBox wrote:

If the leaf basket is completely full after a few minutes, but leaks down
over time something is leaking. If it immediately gets that air in it, then
the prime is not complete, and air is in a high spot in the line that can be
sucked to the leaf basket on starting the pump. If the lid of the leaf trap
is not thoroughly sealed, it will leak air. They make a grease for the
rubber ring, it is somewhat expensive but works. If there are any leaks in
pipe joints that are exposed to air, they will also leak air in. Ideally,
their should be no air in the leaf trap.


Thanks RTB and Roy. I think you are right about there being a leak
somewhere. I let the pump run all night last night and while there is
still good flow from the filters, there is a lot of bubbling coming up
through the media. I have attempted to go back and re-seal around the
pvc joints with primer and cement. Still the water drops down to just
above the inlet. And it sounds like there is a lot of cavitating at the
impeller. That can't be good. There is a "bleed" valve on the elbow
coming out of the pond but I flood it and it is sealed with teflon
tape. Could this still be leaking even with the tape?
So, aside from taking a hack saw to the pipe and starting over (on the
plumbing outside the pond) I am at a lose. Any other suggestions? I
thought about putting in a 1/4 inch bleed valve in the elbow at the
highest point in the line and try to bleed off the air bubbles as the
line floods. The other thing would be to cut the line and fill it up
making sure the air is out, rejoin with a flexible coupling.
Thanks for any additional suggestions. This puppy is a frustrating
little thing.
W. Dale