with the power can I don't know why your having so much troble.it's simple 1 man job, an cover has too be on the MC for pressure. your using a pressured up can on the M/C. I used a hand vaccum pump and never had a problem.with the dual mc do you have a porpurshio.n valve.don't know if I spelled that right ;but someone will get that right. hand vaccum pump no cover needed.just keep eye on fluid level
