I have Bigfoot levelers, single pump system I installed, and no they should not bleed or loose pressure at all. As 10scDust mentioned if there is any air in the system on the lift side of the jacks you'll never get a firm feel and the coach will bounce on the jacks as if the coach is still on the suspension.
Per Quadra's troubleshooting guide (
http://nebula.wsimg.com/cb7bc4c09b8c...&alloworigin=1) you should -
1. Check fluid level (low level you will also not get full extension on all jacks)
2. Check for leaks in hydraulic lines/fittings for leaks (would be obvious with oil on the ground).
3. Possibly plumbed backwards (post install test should have caught)
4. Relief Valves have failed on pump motor
(what I suspect)
5. Hydraulic seal failure, check for oil around bottom of cylinder (obvious indications).
You can always give Quadra a call, 1-800-752-9815 or 269-483-9633.
Bigfoot Hydraulic Leveling System Support