How much should I expect to pay?

[wyochimneysweep]

a cheap vacuum pump will rearly pull a vacuum to 29 in of hg like a pro evacuation machine that meets the current regs. be careful not to go to cheap.

 

[96eb96]

a cheap vacuum pump will rearly pull a vacuum to 29 in of hg like a pro evacuation machine that meets the current regs. be careful not to go to cheap.

The electric ones we linked to are for professional use and can pull very close to 29in. They are sold to NAPA and other professional tool distributors, I was told so by the manufacturer. The compressor operated ones are crap.

Also, you can evac when the truck is warm, and leave it run for a few hours. Maybe the pro machine can pull a bit more vac, the extra time on the smaller machine could actually remove more moisture.

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=98076

Here is a 2.5 CFM one, the only benefit to a higher CFM is if you are evacuating a larger system.

 

[wyochimneysweep]

i don't trust things from harbor frieght or napa. good luck with it. the pumps sold to snap on maybe be the manfacutre but snap on as better quality control so they get the good pumps and the ones barely pass get passed on to the other outlets