Pump/Air Issues

I got a new pump a month or so back from Morebeer, and in general it works great. However, as a pump newbie I've had an issue--when I am pumping liquids over about 3 or 4 feet above the pump, if there is any line in the air at all then it won't move any liquid. Getting air in the line, at least with the plumbing and setup I have, is inevitable. Right now to fix the issue, I disconnect a hose and either use good 'ol mouth suction, or lower the hose basically to the ground and let gravity do it's job.

So what am I doing wrong, and how can I make this easier on myself? It's not a deal breaker, but it certainly is annoying. This is the guy I purchased: http://morebeer.com/view_product/17311/103556/March_High_Temperature_Brewing_Pump

It appears that it usually works correctly, yes? Does it not work at all sometimes? How is air getting in to the lines? Are you gravity feeding the pump? I know, I know, lots of questions to your question.

When I sparge I pump water up from the pump probably 6ft and occasioinally it will loose it's prime. To fix the issue I simply turn it off, let it settle down, and then turn it on again. But I also keep the ball valves open when doing this.

No, not a lot of questions whutever. The intake for the pump is about eight inches below the two kettles I prime it with--boil kettle and mash tun. The lines are flexible, so right now it isn't always a straight shot up or down, and I have four or so valves to control where the liquid can go. Should I take pictures or make a vid? The pump seems fine, I think my plumbing is probably the issue. I may be related to Goldberg

Pictures are always good. Given it's a gravity pump I'd recommend a visit to the March web site to see if there's a minimum height requirement for feeding the inlet. I know when I first started brewing my inlet feed was only about 12" above the pump inlet side and I had the same issue you're experiencing from time to time and would fix it the same way you are. However, after I rebuilt my brew stand and raised it significantly this issue went away.

IDK but perhaps if there's a lot of flex in your lines this might be causing your problem? At any point do the flexible lines drop below the inlet valve?

Ah, well then that might be the culprit. The info on the Morebeer website said 'pump lower than liquid source', but I took that to mean get it lower but as close as you can to the liquid source. Likely stupid of me.