we replaced a sandpoint because the pipe fittings were leaking. we put the new point down an extra 2ft . we did use drive cuplings and a drive cap. Now it will not hold it's prime. also replaced the check valve. Is there such a thing as goihg past the water?? We also have the water pipe inside a casing pipe, could this cause a problem? the point and water pipe is about 8ft below where the casing pipe starts.