Did I get a turkey?

[Voyeurger]

Guys,
I bought this vacuum pump new on Ebay.

2Stage Rotary Vane Deep Vacuum Pump 6CFM Bagging HVAC Tool+Valve Continuous Duty Item Id: 390373843079 End time: Dec-21-11 16:54:13 PST

It worked fine on a test layup (which was only about a foot long). Then, when I did my first serious layup, (about 8 feet long and flat) it took 45 minutes just to empty the bag air! Never did get decent pressure. Layup pretty much worthless (and ugly to boot). Of course I spent that 45 minutes frantically trying to find leaks. I could find none. A couple days ago I tried another big layup. I had torn the whole setup (PVC piping, catch bottle) apart and started over with a clean, airtight setup. Same thing happened. This time I was ready though. I stuck a small nozzle on my shop vac, poked it through the bag, and when I turned it on, it immediately sucked the back hard against the layup. My gauge was still reading zero as I ran around checking for leaks and squeezing bag caulk. Eventually the gauge moved to 1 inHg. This with the Ebay pump AND shop vac going.
I realize that vacuum pumps are slow and steady workhorses, but, how long should it take to get a large bag tight to the layup? Would a shop vac always win this race? What should my gauge peak at if I put it directly onto the pump? I think I've got a crappy pump. It was impossible to leak check by shutting off the pump because the shop vac hose would have let the bag inflate leaks or no.
Anybody out there with similar pumps or experienced with same, I'd sure like to know if I've bought a turkey or if I AM a turkey.:ermm:

Thanks.
Gary

 

[LOFT]

 

[wsimpso1]

 

[rheuschele]

 

[Voyeurger]

 

[Voyeurger]

 

[Voyeurger]

 

[Hot Wings]

 

[davidb]

 

[Voyeurger]

 

[Voyeurger]

 

[davidb]

 

[roverjohn]

 

[davidb]

 

[Rom]

 

[rheuschele]

 

[Voyeurger]

 

[Voyeurger]

 

[orion]

 

[Voyeurger]